You searched for subject:(Ecosystem respiration).
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University of Georgia
1.
Song, Chao.
Carbon flux across scales in a changing climate.
Degree: 2018, University of Georgia
URL: http://hdl.handle.net/10724/38550 
► Ecological patterns are scale dependent. Understanding how and why ecological patterns vary across scales is a central problem in ecology. Stream metabolism and soil respiration,…
(more)
▼ Ecological patterns are scale dependent. Understanding how and why ecological patterns vary across scales is a central problem in ecology. Stream metabolism and soil respiration, two important processes in the global carbon cycle, are
particularly scale dependent. In this dissertation, I employed a dynamic modeling approach to address multiple aspects related to the issue of scale in stream metabolism and soil respiration. Specifically, in chapter 2, I used a dynamic model of
dissolved oxygen to quantify the temperature sensitivity of whole-stream metabolism in streams from six biomes, ranging from the tropics to the Arctic. I found that warming leads to convergence in stream metabolic balance, realized as reduced inter-site
variability of GPP/ER. The GPP/ER ratio in streams with higher temperature and higher current GPP/ER is predicted to decrease in response to warming, whereas in streams with lower temperature and lower current GPP/ER it is expected to increase, although
by a smaller magnitude. In chapter 3, I compared reach-scale metabolism quantified using open channel method and habitat-scale metabolism quantified using chamber incubations. I found that the reach-to-habitat ratio of GPP and ER, standardized to the
same light and temperature conditions, decreased with the variance of habitat-scale metabolism within a reach. By combining theoretical analyses and numeric simulations, I showed that the heterogeneity of habitat-scale metabolism within a reach, the
negative correlations between light and GPP per light, and temperature used for habitat-scale incubations, could explain this pattern of mismatch between reach and habitat scale metabolism. In chapter 4, I demonstrated the importance of recognizing soil
respiration as an aggregated process. I showed that aggregating over space influenced temperature sensitivity, but aggregation over time did no alter temperature sensitivity. I also demonstrated that recognizing soil respiration as the sum of
contributions from distinct substrate pools could explain several often observed relationships between temperature sensitivity and temperature, and influenced interpretations of the mechanisms driving changes in temperature sensitivity of soil
respiration. Collectively, these studies demonstrated scale dependency of soil respiration and stream metabolism, and highlighted the utility of dynamic modeling as a central approach to tackling the issue of scale.
Subjects/Keywords: scale; stream metabolism; gross primary production; ecosystem respiration; temperature sensitivity; soil respiration; global warming
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APA (6th Edition):
Song, C. (2018). Carbon flux across scales in a changing climate. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/38550
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Song, Chao. “Carbon flux across scales in a changing climate.” 2018. Thesis, University of Georgia. Accessed January 17, 2021.
http://hdl.handle.net/10724/38550.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Song, Chao. “Carbon flux across scales in a changing climate.” 2018. Web. 17 Jan 2021.
Vancouver:
Song C. Carbon flux across scales in a changing climate. [Internet] [Thesis]. University of Georgia; 2018. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10724/38550.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Song C. Carbon flux across scales in a changing climate. [Thesis]. University of Georgia; 2018. Available from: http://hdl.handle.net/10724/38550
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
2.
Schröer, Cosima.
Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming.
Degree: Ecology and Environmental Sciences, 2020, Umeå University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169537
► Terrestrial arctic ecosystems store large amounts of carbon (C). With global warming, this C might be released into the atmosphere as CO2 by stimulation…
(more)
▼ Terrestrial arctic ecosystems store large amounts of carbon (C). With global warming, this C might be released into the atmosphere as CO2 by stimulation of soil microbial degradation. At the same time, CO2 uptake in plants is enhanced, which might, in parts, offset CO2 losses. Yet, the future balance of these two contrasting feedbacks remain uncertain. This study aimed to better understand changes of input and output CO2 fluxes in an arctic tussock tundra ecosystem in response to global warming, with a special focus on the contrast between two sub-ecosystem habitats, the tussocks and the space between tussocks. An experimental setup was used, where snow fences simulated winter warming by increasing snow depth, and open top chambers simulated summer warming. Daytime ecosystem respiration (ER), reflecting the outward CO2 flux, gross ecosystem production (GEP), reflecting the inward CO2 flux, and net ecosystem exchange (NEE), reflecting the net balance of both, were measured in the summer 2019 in the tussock and the intertussock habitat. In the tussock, both ER and GEP were as twice as high compared to the intertussock and increased with summer warming in a similar magnitude, resulting in an unchanged NEE. Fluxes in the intertussock were not altered with summer warming. Winter warming had no significant effects on ER and GEP in neither of the habitats. However, winter warming increased NEE and green biomass in the intertussock, indicating that in this habitat, plants benefit from warmer winter soil temperatures. Interaction effects of winter and summer warming underline the role of ecological processes outside the summer season, which are to date poorly understood. Contrasting responses of the two sub-ecosystem habitats highlight the challenges in predicting future C balances that are caused by small-scale spatial and temporal heterogeneity of C dynamics.
Subjects/Keywords: arctic tundra; carbon dioxide fluxes; climate warming; ecosystem respiration; gross ecosystem production; net ecosystem exchange; Natural Sciences; Naturvetenskap
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APA (6th Edition):
Schröer, C. (2020). Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming. (Thesis). Umeå University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169537
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Schröer, Cosima. “Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming.” 2020. Thesis, Umeå University. Accessed January 17, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169537.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Schröer, Cosima. “Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming.” 2020. Web. 17 Jan 2021.
Vancouver:
Schröer C. Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming. [Internet] [Thesis]. Umeå University; 2020. [cited 2021 Jan 17].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169537.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Schröer C. Arctic Soils in a Warming Climate: Plot-scale Changes of CO2 Fluxes after Five Years of Experimental Warming. [Thesis]. Umeå University; 2020. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169537
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Colorado State University
3.
Speckman, Heather.
Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic.
Degree: MS(M.S.), Ecology, 2013, Colorado State University
URL: http://hdl.handle.net/10217/81084
► Eddy covariance (EC) enables continuous estimates of carbon, water, and energy fluxes, and a global network of >500 sites (www.fluxnet.ornl.gov) has resulted in major advances…
(more)
▼ Eddy covariance (EC) enables continuous estimates of carbon, water, and energy fluxes, and a global network of >500 sites (www.fluxnet.ornl.gov) has resulted in major advances in understanding
ecosystem-scale biogeochemical cycling. However, long-term sums of net
ecosystem exchange, photosynthesis and
respiration fluxes have uncertainties because of potential measurement biases in
respiration fluxes at night. Many studies have demonstrated that EC estimations of flux during the night are lower than chamber measurements – with low turbulence at night potentially causing the difference. A bark beetle outbreak at the GLEES Ameriflux site provided a unique opportunity to compare chamber and EC estimates of
ecosystem respiration (R) under conditions of high turbulence (summer night mean u* = 0.7 m s-1) and 85% mortality of the aboveground respiring biomass due to a bark beetle epidemic. Chamber-based estimates of R were developed from periodic foliage, wood and soil CO2 efflux measurements fit to models of phenological seasonal change and diurnal temperature response. These models estimated
ecosystem mean nightly
respiration to have declined 32% after the bark beetle epidemic (7.0 ±0.22 μmol m-2 s-1 in 2005 to 4.8 ±0.16 μmol m-2 s-1 in 2011). The decrease was entirely due to the loss of aboveground
respiration, soil efflux remained constant throughout the epidemic. Unlike chamber estimates, nighttime EC measurements did not decline after 85% of the forest basal area had been infested or killed by bark beetles, mean nighttime NEE of 3.0 μmol m-2 s-1 for 2005 and 2011. These EC values were significantly lower than chamber estimates of
respiration for the same time periods (58% lower in 2005, and 34% in 2011). Despite the large difference in values, the two estimates of R were correlated (yearly r2 ranging from 0.18-0.60). This study suggests that the traditional discrepancy of nighttime EC and chamber estimates of
ecosystem respiration are not caused by insufficient turbulence (results proved robust to extreme u* filter > 0.7 m s-1). Other sources of error are investigated for both techniques. To further explore this discrepancy, we suggest the installation of a second EC system below the canopy to improve understanding of air flows and fluxes throughout the
ecosystem. This discrepancy must be resolved before scientific confidence can be attained in the true value of
ecosystem carbon flux.
Advisors/Committee Members: Ryan, Michael G. (advisor), Parton, William J. (advisor), Ham, Jay M. (committee member), Denning, A. Scott (committee member).
Subjects/Keywords: bark beetles; chamber; ecosystem respiration; eddy covariance; turbulence; u* filtering
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APA ·
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APA (6th Edition):
Speckman, H. (2013). Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/81084
Chicago Manual of Style (16th Edition):
Speckman, Heather. “Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic.” 2013. Masters Thesis, Colorado State University. Accessed January 17, 2021.
http://hdl.handle.net/10217/81084.
MLA Handbook (7th Edition):
Speckman, Heather. “Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic.” 2013. Web. 17 Jan 2021.
Vancouver:
Speckman H. Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10217/81084.
Council of Science Editors:
Speckman H. Forest respiration from eddy covariance and chamber measurements under high turbulence and a bark beetle epidemic. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/81084
University of Kansas
4.
Kelly, Michelle Catherine.
High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river.
Degree: MA, Ecology & Evolutionary Biology, 2019, University of Kansas
URL: http://hdl.handle.net/1808/30207
► Our current understanding of the relationship between nitrate (NO3-) uptake and energy cycling in rivers is primarily built on studies conducted in low-nutrient (NO3- <…
(more)
▼ Our current understanding of the relationship between nitrate (NO3-) uptake and energy cycling in rivers is primarily built on studies conducted in low-nutrient (NO3- < 1 mg-N L-1), small (discharge < 1 m3 s-1) systems. Recent advances in sensor technology have allowed for continuous measures of whole-river NO3- uptake, allowing us to address how the relationship between nutrient uptake and metabolism changes over time and space during a nutrient addition in a large river. We treated a six-month controlled nitrogen (N) waste release into the Kansas River (conducted by the City of Lawrence, KS) as an
ecosystem-scale nutrient addition experiment. We deployed four NO3- and dissolved oxygen sensor arrays along a 33 km study reach from February to May 2018 to continuously monitor diel NO3 – N and stream metabolism. We then evaluated NO3- uptake using the extrapolated diel method and modeled stream metabolism using the single station method. We found the highest uptake rates closest to the nutrient release point (866 g-N m-2 d1), despite high NO3- supply (4.36 mg-N L-1). Net
ecosystem productivity was increasingly autotrophic with distance from the release, with the highest
respiration rates observed closest to the release point (7.09 g-O2 m-2 d1). However, uptake was decoupled from metabolism metrics, likely due to fine-scale hydrologic and biotic factors. Overall, our work sheds light on the ability of large rivers to retain and transform nutrients, while demonstrating that the fine-scale mechanisms that regulate nutrient retention in large rivers are still largely unknown.
Advisors/Committee Members: Burgin, Amy J (advisor), Husic, Admin (cmtemember), Sikes, Benjamin A (cmtemember).
Subjects/Keywords: Biogeochemistry; Ecology; Limnology; Disturbance; Ecosystem respiration; Nutrient cycling; Primary production; Sensors
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APA (6th Edition):
Kelly, M. C. (2019). High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river. (Masters Thesis). University of Kansas. Retrieved from http://hdl.handle.net/1808/30207
Chicago Manual of Style (16th Edition):
Kelly, Michelle Catherine. “High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river.” 2019. Masters Thesis, University of Kansas. Accessed January 17, 2021.
http://hdl.handle.net/1808/30207.
MLA Handbook (7th Edition):
Kelly, Michelle Catherine. “High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river.” 2019. Web. 17 Jan 2021.
Vancouver:
Kelly MC. High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river. [Internet] [Masters thesis]. University of Kansas; 2019. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1808/30207.
Council of Science Editors:
Kelly MC. High supply, high demand: A unique nutrient addition decouples nitrate uptake and metabolism in a large river. [Masters Thesis]. University of Kansas; 2019. Available from: http://hdl.handle.net/1808/30207
University of Melbourne
5.
HINKO-NAJERA, NINA.
Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia.
Degree: 2016, University of Melbourne
URL: http://hdl.handle.net/11343/115244
► Forest ecosystems are one of the most important terrestrial carbon sinks of anthropogenic derived atmospheric CO2 but future trends and strength of this forest carbon…
(more)
▼ Forest ecosystems are one of the most important terrestrial carbon sinks of anthropogenic derived atmospheric CO2 but future trends and strength of this forest carbon sink are uncertain. This uncertainty is mainly related to the high temporal (inter-annual) and regional variability in the net ecosystem exchange (NEE) – the balance of carbon gain (gross primary production, GPP) and carbon loss (ecosystem respiration, ER) – of forest ecosystems in response to climate variability. Limited data are available on forest ecosystem carbon dynamics, including respiration processes, for Australian forest systems, in particular dry temperate eucalypt (broadleaved evergreen) forests. Temperate eucalypt forests differ considerably from temperate coniferous and deciduous forests in the Northern Hemisphere in phenology and climatic conditions and thus might present different ecosystem carbon dynamics. This thesis investigated the temporal dynamics of NEE, its component fluxes, in particular RS and its underlying processes, and their dependencies on key environmental drivers at Wombat State Forest a dry temperate eucalypt forest in south-eastern Australia, 120 km west of Melbourne.
We used the eddy covariance (EC) technique to investigate the seasonal and inter-annual variability and environmental controls of NEE, GPP and ER for three years from 2010 to 2012 at the Wombat Forest flux tower site. GPP exceeded ER almost continually, with an average ER/GPP ratio of 0.58, such that the forest was a large and constant carbon sink throughout the study period with a mean of -1062 ± 53 g C m-2 yr-1 (-976 to -1158 g C m-2 yr-1). Gross CO2 ecosystem fluxes showed no significant inter-annual variability but all CO2 ecosystem fluxes had a pronounced seasonality. Both GPP and ER where in phase and peaked during summer whereas NEE peaked in early spring and again in summer. High NEE in spring was caused by a delayed increase in ER due to low temperatures. A random forest analysis showed that variability in GPP was mostly explained by incoming solar radiation whilst air temperature was the main environmental driver of ER on seasonal and inter-annual time scales. The forest experienced very high rainfall during the first two years of this three year period so that soil moisture content remained relatively high and the forest was not water limited. Our results demonstrated that carbon exchange dynamics in this dry temperate eucalypt forest were different in their seasonal behaviour from temperate deciduous or coniferous forests studies in the Northern Hemisphere. Furthermore our results show the potential of dry temperate eucalypt forests to sequester large amounts of carbon in the absence of drought.
To investigate the seasonal and inter-annual variation of RS and to improve our understanding on its key environmental drivers, soil temperature and soil moisture, we continually measured RS at high temporal resolution (1.5 to 3 hourly) over four years (2010 – 2014) using an automated chamber system at the Wombat Forest flux site. Observed RS…
Subjects/Keywords: dry temperate sclerophyll forest; soil CO2 efflux; eddy covariance; net ecosystem productivity; random forest approach; temperature sensitivity; soil moisture; ecosystem respiration; heterotrophic respiration; belowground autotrophic respiration; throughfall reduction; root exclusion
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APA (6th Edition):
HINKO-NAJERA, N. (2016). Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/115244
Chicago Manual of Style (16th Edition):
HINKO-NAJERA, NINA. “Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia.” 2016. Doctoral Dissertation, University of Melbourne. Accessed January 17, 2021.
http://hdl.handle.net/11343/115244.
MLA Handbook (7th Edition):
HINKO-NAJERA, NINA. “Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia.” 2016. Web. 17 Jan 2021.
Vancouver:
HINKO-NAJERA N. Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia. [Internet] [Doctoral dissertation]. University of Melbourne; 2016. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/11343/115244.
Council of Science Editors:
HINKO-NAJERA N. Soil respiration and its contribution to the net ecosystem carbon exchange in a dry temperate eucalypt forest in south-eastern Australia. [Doctoral Dissertation]. University of Melbourne; 2016. Available from: http://hdl.handle.net/11343/115244
Virginia Commonwealth University
6.
Tassone, Spencer.
A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements.
Degree: MS, Biology, 2017, Virginia Commonwealth University
URL: https://doi.org/10.25772/5906-DS96
;
https://scholarscompass.vcu.edu/etd/4988
► Diel dissolved oxygen (DO) data were used to characterize seasonal, inter-annual, and longitudinal variation in production and respiration for the James River Estuary. Two…
(more)
▼ Diel dissolved oxygen (DO) data were used to characterize seasonal, inter-annual, and longitudinal variation in production and
respiration for the James River Estuary. Two computational methods (Bayesian and bookkeeping) were applied to these data to determine whether inferences regarding DO metabolism are sensitive to methodology. Net metabolism was sensitive to methodology as Bayesian results indicated net heterotrophy (production <
respiration) while bookkeeping results indicated net autotrophy (production >
respiration). Differences in net metabolism among the methods was due to low seasonal variation in
respiration using the Bayesian method, whereas bookkeeping results showed a strong correlation between production and
respiration. Bayesian results suggest a dependence on allochthonous organic matter (OM) whereas bookkeeping results suggest that metabolism is dependent on autochthonous OM. This study highlights the importance in considering the method used to derive metabolic estimates as it can impact the assessment of trophic status and sources of OM supporting an estuary.
Advisors/Committee Members: Dr. Paul Bukaveckas, Dr. Scott Neubauer, Dr. Daniel McGarvey, Dr. S. Leigh McCallister.
Subjects/Keywords: Metabolism; Estuary; Ecosystem respiration; Primary production; Net ecosystem metabolism; James river; Marine Biology; Terrestrial and Aquatic Ecology
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APA (6th Edition):
Tassone, S. (2017). A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements. (Thesis). Virginia Commonwealth University. Retrieved from https://doi.org/10.25772/5906-DS96 ; https://scholarscompass.vcu.edu/etd/4988
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tassone, Spencer. “A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements.” 2017. Thesis, Virginia Commonwealth University. Accessed January 17, 2021.
https://doi.org/10.25772/5906-DS96 ; https://scholarscompass.vcu.edu/etd/4988.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tassone, Spencer. “A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements.” 2017. Web. 17 Jan 2021.
Vancouver:
Tassone S. A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements. [Internet] [Thesis]. Virginia Commonwealth University; 2017. [cited 2021 Jan 17].
Available from: https://doi.org/10.25772/5906-DS96 ; https://scholarscompass.vcu.edu/etd/4988.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tassone S. A comparison of computational methods for estimating estuarine production and respiration from diel open water dissolved oxygen measurements. [Thesis]. Virginia Commonwealth University; 2017. Available from: https://doi.org/10.25772/5906-DS96 ; https://scholarscompass.vcu.edu/etd/4988
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Vienna
7.
Saad, Asaad.
CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria.
Degree: 2017, University of Vienna
URL: http://othes.univie.ac.at/46033/
► Moore bedecken ca. 3% der Land- und Süßwasseroberfläche der Erde, was über über vier Millionen km2 entspricht. Sie enthalten ein Drittel des weltweiten Bodenkohlenstoffs. Im…
(more)
▼ Moore bedecken ca. 3% der Land- und Süßwasseroberfläche der Erde, was über über vier Millionen km2 entspricht. Sie enthalten ein Drittel des weltweiten Bodenkohlenstoffs. Im Pürgschachen-Moor im Ennstal (Steiermark, Österreich) kommen vier verschiedene Pflanzenzusammensetzungen vor, an denen im Zuge dieser Studie CO2-Austauschflüsse gemessen wurden. Im Frühjahr, Sommer und Herbst wurden Probennahmen und Messungen mit der geschlossenen dynamischen Haubenmessmethode und Infrarot-Gasanalysatoren durchgeführt. Untersucht wurden jahres- und tageszeitliche Änderungen der Ökosystemrespiration (ecosystem respiration - Reco), Bruttoprimärproduktion (gross primary production - GPP) und des Netto-Ökosystemaustauschs (net ecosystem exchange - NEE) wurden über die photosynthetisch aktive Strahlung (PAR) und Bodentemperatur in 2 cm Tiefe gemessen, wobei auch Grundwasserspiegelschwankungen berücksichtigt wurden. Untersucht wurde die Wirkung der verschiedenen Pflanzenzusammensetzungen der vier Standorte auf Reco, GPP und NEE. Schließlich wurden Reco, GPP und NEE modelliert, um mit den Schätzungen der Flüsse den Gesamt-CO2-Austausch pro Quadratmeter für das Ökosystem über das Jahr zu berechnen.
Einerseits zeigte Reco in der Studie eine starke positive Korrelation mit Temperaturänderungen über die Tageszeit und saisonalen Unterschieden, andererseits war die Korrelation zwischenRespirationund Grundwasserspiegel gering. GPP stieg mit PAR-Zunahme in Übereinstimmung mit der Lichtsättigungskurve. NEE zeite bei niedrigen PAR-Werten CO2-Freisetzung und bei PAR-Zunahme herhöhte Produktion und dadurch CO2-Aufnahme durch das System. Wärmere Jahreszeiten zeigten höhere Produktionsflüsse, was darauf hinweist, dass PAR nicht der einzige Faktor war, der das GPP beeinflusst, sondern auch Temperatur eine Rolle spielt.
Laut Modell zeigen Standorte PM2 und PM4 "Pinus mugo" (Pflanzen in PM4 sind größer als PM2) CO2-Freisetzung (jährliche NEE-Beträge +1.227 kg m-2 y-1 in PM2), während PM3 "Calluna vulgaris" CO2-Aufnahme zeigt (jährliche NEE betrug -1.129 kg m-2 y-1) und PM1 "Eriophorum vaginatum & Rhynchospora alba" niedrige NEE-Flüsse zeigen. Die höchste jährliche GPP befand sich in PM3 (-3.854 kg m-2 y-1) und der höchste jährliche Reco in PM2 (3.761 kg m-2 y-1). Diese Resultate legen nahe, dass die Verteilung der Pflanzenzusammensetzung und die Größe der Pflanzen eine bedeutende Rolle in Mooren spielen und den Kohlenstoffaustausch innerhalb des Ökosystems als Parameter beeinflussen, und dadurch auch Einfluss auf den Status des Ökosystems als CO2-Senke oder Quelle haben.
Peatlands cover over four million km2 representing 3% of the land and freshwater surface of the planet and contains one third of the world’s soil carbon. In this study, CO2 exchange fluxes were measured in four sites located in Püergschachen Moor in the Styrian Enns valley, Austria representing four different plant compositions in the study area. Measurements were done during spring, summer and autumn using closed dynamic chamber approach and gas measurements were made using…
Subjects/Keywords: 38.47 Moore; Moore / Ökosystemrespiration / Bruttoprimärproduktion / Netto-Ökosystem-Austausch / Pflanzenzusammensetzung; peatland / ecosystem respiration / gross primary production / net ecosystem exchange / plant composition
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APA ·
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Manager
APA (6th Edition):
Saad, A. (2017). CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria. (Thesis). University of Vienna. Retrieved from http://othes.univie.ac.at/46033/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Saad, Asaad. “CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria.” 2017. Thesis, University of Vienna. Accessed January 17, 2021.
http://othes.univie.ac.at/46033/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Saad, Asaad. “CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria.” 2017. Web. 17 Jan 2021.
Vancouver:
Saad A. CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria. [Internet] [Thesis]. University of Vienna; 2017. [cited 2021 Jan 17].
Available from: http://othes.univie.ac.at/46033/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Saad A. CO2 fluxes of four different plant compositions in the Püergschachen Moor in the Styrian Enns valley, Austria. [Thesis]. University of Vienna; 2017. Available from: http://othes.univie.ac.at/46033/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Chicago
8.
Qasem, Karoline.
The Effect of Urbanization and Dam Removal on Stream Metabolism.
Degree: 2018, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/23004
► The main goal of this dissertation is to explore the influence of urbanization and dam removal on stream function represented by stream metabolism (i.e., gross…
(more)
▼ The main goal of this dissertation is to explore the influence of urbanization and dam removal on stream function represented by stream metabolism (i.e., gross primary production (GPP),
ecosystem respiration (ER) and net
ecosystem production (NEP)). Moreover, the research examines dam removal as a means of restoring stream metabolism. In a study of seven sites around the Chicago region during summer and fall of 2009-2013, results showed that stream GPP and ER decreased during storms, but on average ER show significantly greater resistance than GPP. After floods, both ER and GPP recovered to pre-flood levels within approximately 1-10 days, with no significant difference between GPP and ER resilience to floods. Results from this study demonstrate that GPP in urban streams is more susceptible to disturbance than the ER. Low production as a result of continued flood events can result in low oxygen levels in water and therefore can affect organisms that prefer specific DO levels.
This dissertation demonstrates that
ecosystem metabolism changes significantly following dam removal. More specifically, dam removal increased GPP and ER levels at the upstream and downstream dam removal sites, immediately after removal of the dam. Away from the studied dam, a reference site showed only a small seasonal decline in GPP and ER across the same months. Metabolism in the upstream and downstream sections of the restored rivers shows similar GPP and ER rates and similar rates to a reference site following dam removal. Moreover, dam removal moves the streams towards autotrophy by increasing GPP more than ER. Overall, I concluded that dam removal can restore aquatic ecosystems by enhancing metabolism rates even in non-production seasons (i.e., winter). The study suggests that dam removal should be considered as a preferable means of restoration for areas with low GPP and ER. Moreover, the dam removal timing can also play an important role on the behavior of metabolism response to dam removal (e.g., if the dam was removed in spring where algae bloom, GPP can increase to much higher levels). A future research should investigate multiple dam removal case studies to address the influence of seasonality on dam removal.
Finally, in a study of 50 watersheds across a gradient in urban intensity (18 sites located on 13 watersheds in the Midwestern US during summer/fall periods.), urbanization was quantified using the urban land use gradient index (ULUG) which is derived from infrastructure, land cover, and population variables, in addition to the flashiness index which is derived from normalized variation of daily flow regime. I showed that both GPP and ER decreased sharply (in absolute value) above 23.8 ULUG. Moreover, results concluded that urbanization is a major controlling factor on stream metabolism as it increases heterotrophy by reducing GPP more than ER. This study suggests that metabolism restoration projects should be targeted to high urban intensities. A future study can include much larger number of sites with different site…
Advisors/Committee Members: Vitousek, Sean (advisor), Derrible, Sybil (committee member), Schulenberg, Joseph (committee member), O'Connor, Ben (committee member), Hoellein, Timothy (committee member), Khodadoust, Amid (chair).
Subjects/Keywords: Stream metabolism; urban streams; urbanization; stream function; flood; gross primary production; ecosystem respiration; net ecosystem production
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APA (6th Edition):
Qasem, K. (2018). The Effect of Urbanization and Dam Removal on Stream Metabolism. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/23004
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Qasem, Karoline. “The Effect of Urbanization and Dam Removal on Stream Metabolism.” 2018. Thesis, University of Illinois – Chicago. Accessed January 17, 2021.
http://hdl.handle.net/10027/23004.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Qasem, Karoline. “The Effect of Urbanization and Dam Removal on Stream Metabolism.” 2018. Web. 17 Jan 2021.
Vancouver:
Qasem K. The Effect of Urbanization and Dam Removal on Stream Metabolism. [Internet] [Thesis]. University of Illinois – Chicago; 2018. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10027/23004.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Qasem K. The Effect of Urbanization and Dam Removal on Stream Metabolism. [Thesis]. University of Illinois – Chicago; 2018. Available from: http://hdl.handle.net/10027/23004
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Alberta
9.
Shi, Zheng.
Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada.
Degree: MS, Department of Renewable Resources, 2010, University of Alberta
URL: https://era.library.ualberta.ca/files/j9602181j
► Afforestation and stand development can significantly affect soil respiration and net ecosystem productivity (NEP). I studied 1) the effects of afforestation on NEP by comparing…
(more)
▼ Afforestation and stand development can significantly
affect soil respiration and net ecosystem productivity (NEP). I
studied 1) the effects of afforestation on NEP by comparing
cropland previously planted to barley (on a
barley-barley-alfalfa-alfalfa-alfalfa rotation) and that converted
to a hybrid poplar (Populus deltoides × Populus × petrowskyana var.
Walker) plantation and 2) the NEP along a chronosequence of stands
aged 5-, 8-, 14-, and 16-year old in 2009 in central Alberta,
Canada. Soil respiration and NEP decreased in the first two to
three years after afforestation, while both generally increased
with stand development. The ecosys model was used to simulate
carbon dynamics in the plantations over a 20-year rotation under
contrasting soil conditions. Soil conditions of the 14-year-old
plantation accumulated the greatest amount of ecosystem carbon over
the whole rotation. The research indicated that plantations could
be a net carbon source in the first few years after afforestation
and then became a net carbon sink, helping to mitigate net CO2
emissions for the remainder of the rotation.
Subjects/Keywords: land use change; net ecosystem productivity; soil respiration; hybrid poplar; stand age; climate change
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APA (6th Edition):
Shi, Z. (2010). Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/j9602181j
Chicago Manual of Style (16th Edition):
Shi, Zheng. “Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada.” 2010. Masters Thesis, University of Alberta. Accessed January 17, 2021.
https://era.library.ualberta.ca/files/j9602181j.
MLA Handbook (7th Edition):
Shi, Zheng. “Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada.” 2010. Web. 17 Jan 2021.
Vancouver:
Shi Z. Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada. [Internet] [Masters thesis]. University of Alberta; 2010. [cited 2021 Jan 17].
Available from: https://era.library.ualberta.ca/files/j9602181j.
Council of Science Editors:
Shi Z. Afforestation and stand age affected soil respiration and
net ecosystem productivity in hybrid poplar plantations in central
Alberta, Canada. [Masters Thesis]. University of Alberta; 2010. Available from: https://era.library.ualberta.ca/files/j9602181j
Colorado State University
10.
Asao, Shinichi.
Variation in carbon cycling among four tree species in a tropical rain forest.
Degree: PhD, Ecology, 2014, Colorado State University
URL: http://hdl.handle.net/10217/83711
Subjects/Keywords: allocation; ecophysiology; ecosystem; photosynthesis; production; respiration
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APA (6th Edition):
Asao, S. (2014). Variation in carbon cycling among four tree species in a tropical rain forest. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/83711
Chicago Manual of Style (16th Edition):
Asao, Shinichi. “Variation in carbon cycling among four tree species in a tropical rain forest.” 2014. Doctoral Dissertation, Colorado State University. Accessed January 17, 2021.
http://hdl.handle.net/10217/83711.
MLA Handbook (7th Edition):
Asao, Shinichi. “Variation in carbon cycling among four tree species in a tropical rain forest.” 2014. Web. 17 Jan 2021.
Vancouver:
Asao S. Variation in carbon cycling among four tree species in a tropical rain forest. [Internet] [Doctoral dissertation]. Colorado State University; 2014. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10217/83711.
Council of Science Editors:
Asao S. Variation in carbon cycling among four tree species in a tropical rain forest. [Doctoral Dissertation]. Colorado State University; 2014. Available from: http://hdl.handle.net/10217/83711
University of Maryland
11.
Lee, Dong-Yoon.
The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary.
Degree: Marine-Estuarine-Environmental Sciences, 2014, University of Maryland
URL: http://hdl.handle.net/1903/16249
► Gradients of dissolved oxygen concentrations in seasonally stratified estuarine water columns directly influence microbial composition and metabolic pathways, resulting in annually recurring spatiotemporal chemical gradients…
(more)
▼ Gradients of dissolved oxygen concentrations in seasonally stratified estuarine water columns directly influence microbial composition and metabolic pathways, resulting in annually recurring spatiotemporal chemical gradients of redox-active species. Understanding such microbial responses to variable geochemical conditions and elucidating the diversity of microbial processes are needed to comprehensively identify
ecosystem functions. At first this study describes an investigation of the relationships between microbial processes and geochemical conditions. To assess the contribution of different biological redox processes on carbon and nitrogen cycles in the Chesapeake Bay, we used observational and experimental approaches as well as utilization of monitoring datasets to facilitate an assessment of
ecosystem-level metabolism. Observations revealed a general positive association of community metabolism with strong gradients of redox-related variables and hydrodynamic characteristics, although geochemical and environmental conditions varied seasonally across oxic transitions and interannually across degrees of stratification. The most distinct evidence supporting the positive association were vertical distributions of community
respiration with the highest average rates in the most stratified regions coincident with the depths of the steepest gradient of chemical compounds. Although organic matter availability may be enhanced due to hydrodynamically induced stability, our investigation of factors driving the pattern revealed that differential responses and metabolic strategies of microbial communities result in high
respiration near oxyclines. Investigation of vertical profiles of redox-related variables also revealed that the coexistence of oxidants and reduced compounds further provides an optimal condition for other electron accepting processes, including chemoautotrophy and anoxygenic photoautotrophy. The strong interdependence between environmental conditions and variability in microbial metabolism also reflected in patterns of plankton assemblages. An ammonium mass-balance analysis revealed that increases in vertical ammonium dispersion during severe hypoxia cause a shift of plankton assemblages towards heterotrophy, subsequently supporting a deep secondary microbial food web in the vicinity of oxic/anoxic interface. Overall, results from this research indicate that the estimation of more accurate net
ecosystem metabolism should take into consideration of the highly variable nature of community metabolism associated with both geochemical gradients and stratification.
Advisors/Committee Members: Cornwell, Jeffrey C (advisor).
Subjects/Keywords: Microbiology; Environmental science; Cell composition and concentration; Ecosystem metabolism; Estuary; Hypoxia; Primary production; Respiration
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APA (6th Edition):
Lee, D. (2014). The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/16249
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lee, Dong-Yoon. “The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary.” 2014. Thesis, University of Maryland. Accessed January 17, 2021.
http://hdl.handle.net/1903/16249.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lee, Dong-Yoon. “The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary.” 2014. Web. 17 Jan 2021.
Vancouver:
Lee D. The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary. [Internet] [Thesis]. University of Maryland; 2014. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1903/16249.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lee D. The effects of oxygen transition on community metabolism and nutrient cycling in a seasonally stratified anoxic estuary. [Thesis]. University of Maryland; 2014. Available from: http://hdl.handle.net/1903/16249
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Vienna
12.
Fuchslueger, Lucia.
Partitioning of ecosystem respiration in a beech forest ecosystem.
Degree: 2010, University of Vienna
URL: http://othes.univie.ac.at/8975/
► Wir charakterisierten die Bodenatmung (CO2) und ihre isotopische Zusammensetzung (13C) eines temperaten Buchenwaldes (Fagus sylvatica) im Tages- bzw. Jahresverlauf und untersuchten die Aufteilung der Bodenatmung…
(more)
▼ Wir charakterisierten die Bodenatmung (CO2) und ihre isotopische Zusammensetzung (13C) eines temperaten Buchenwaldes (Fagus sylvatica) im Tages- bzw. Jahresverlauf und untersuchten die Aufteilung der Bodenatmung in ihre autotrophen und heterotrophen Anteile. Die Aufteilung in autotrophe und heterotrophe Bodenatmung wurde durch Vergleichen von Atmungsraten in beringelten und unbehandelten Kontrollflächen erreicht. Zusätzlich untersuchten wir ein umfangreiches Set an potentiellen Substraten und Quellen der Bodenatmung auf ihre δ13C Werte.
In Kontrollflächen war Pflanzenmaterial (Laubstreu, Fein- und Grobwurzeln), sowie organisches Material im Boden (SOM) stärker an 13C abgereichert, als Kohlenhydrate in Pflanzenorganen (Zucker im Phloemsaft, Stärke und Zucker in Wurzeln) und Wurzelatmung, was anzeigt, dass ein größerer Teil von Bodenatmung von kürzlich assimiliertem Kohlenstoff angetrieben wird. Wir nahmen an, dass die Isotopensignatur von gelöstem organischem Kohlenstoff (DOC) die Isotopensignatur der Quellen, wie Wurzelexudate oder Produkte von Abbauprozessen, die zum DOC beitragen widerspiegelt. In Kontrollen war DOC stärker angereichert an 13C als in den geringelten Flächen, und wies ähnliche Isotopensignaturen, wie die der Wurzelzucker auf. Das könnte darauf hindeuten, dass Wurzelexudate einen wesentlichen Anteil am DOC ausmachen.
Beringeln führte zu einem durchschnittlichen Rückgang der Gesamtbodenatmung um 36 % und zu stärker abgereicherten 13C Signaturen von veratmeten CO2 um 1.5 ‰ im Jahresverlauf, was einen Rückgang der autotrophen Atmung und eine Verschiebung Richtung Abbau von Wurzelstreu und SOM anzeigt. Dies wurde auch von stärker abgereicherten Isotopensignaturen im DOC von geringelten Flächen bestätigt.
Wir beobachteten Schwankungen von Bodenatmung und δ13C der Bodenatmung im Tages- und Jahresverlauf. Wir identifizierten Lufttemperatur als Hauptkontrollfaktor für Bodenatmung sowohl in beringelten, als auch in den Kontrollflächen auf verschieden Zeitskalen. In beringelten Flächen korrelierte im Jahresverlauf die Bodenatmung auch mit Bodentemperatur. Die δ13C Werte der Zucker aus dem Phloemsaft wiesen keine signifikanten Veränderungen im Tagesgang auf und korrelierte nicht mit den δ13C Werten der Bodenatmung in Kontrollflächen.
We characterised fluxes of soil respired CO2 and corresponding δ13C values in a temperate beech (Fagus sylvatica) forest on a daily and seasonal time scale to investigate autotrophic and heterotrophic contributions to total soil respiration. Partitioning of soil respiration was achieved by comparing rates of soil respiration in girdled plots with non-girdled controls. Additionally we investigated a comprehensive set of potential substrates and sources of soil respiration for their δ13C values.
In controls bulk plant litter (leaf, fine and coarse root litter) as well as soil organic matter (SOM) were more depleted in 13C than plant carbohydrates (phloem sap sugars, root starch and sugars) and root respiration, indicating that a major part of soil respiration was fuelled by…
Subjects/Keywords: 42.90 Ökologie: Allgemeines; 42.97 Ökologie: Sonstiges; Ökosystematmung / Bodenatmung / Partitionierung von autotropher und heterotropher Atmung / Beringelung / Stabile Isotopen; ecosystem respiration / soil respiration / partitioning of autotrophic and heterotrophic respiration / girdling / stable isotopes
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APA ·
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Manager
APA (6th Edition):
Fuchslueger, L. (2010). Partitioning of ecosystem respiration in a beech forest ecosystem. (Thesis). University of Vienna. Retrieved from http://othes.univie.ac.at/8975/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Fuchslueger, Lucia. “Partitioning of ecosystem respiration in a beech forest ecosystem.” 2010. Thesis, University of Vienna. Accessed January 17, 2021.
http://othes.univie.ac.at/8975/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Fuchslueger, Lucia. “Partitioning of ecosystem respiration in a beech forest ecosystem.” 2010. Web. 17 Jan 2021.
Vancouver:
Fuchslueger L. Partitioning of ecosystem respiration in a beech forest ecosystem. [Internet] [Thesis]. University of Vienna; 2010. [cited 2021 Jan 17].
Available from: http://othes.univie.ac.at/8975/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Fuchslueger L. Partitioning of ecosystem respiration in a beech forest ecosystem. [Thesis]. University of Vienna; 2010. Available from: http://othes.univie.ac.at/8975/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Helsinki
13.
Karim, Md Rezaul.
EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL.
Degree: Department of Agricultural Sciences; Helsingfors universitet, Agrikultur- och forstvetenskapliga fakulteten, Institutionen för lantsbruksvetenskaper, 2017, University of Helsinki
URL: http://hdl.handle.net/10138/228418
► Peat lands are net sinks of carbon (C) and a net source of carbon dioxide (CO2) emissions owing to drainage during the growing season. The…
(more)
▼ Peat lands are net sinks of carbon (C) and a net source of carbon dioxide (CO2) emissions owing to drainage during the growing season. The surface peat layer can be lost because of aerobic decomposition (oxidation) after drainage resulting in emissions of CO2. One way to reduce these emissions is to keep the water table at a high level as much as possible. The resulting anoxic conditions reduce the decomposition of organic matter and hence CO2 emissions. In the current Finnish agri-environmental scheme, the farmers may receive subsidies for controlled drainage on peatlands, and a raised ground water level through controlled drainage could be used as a greenhouse gas mitigation measure.
This study reports the carbon balance of drained peatland under controlled drainage during the growing season in Mouhijärvi, Southwestern Finland. The CO2 fluxes measured with a transparent chamber method were divided into gross primary productivity (GPP) and ecosystem respiration (ER) for modelling based on environmental factors (light and temperature) and canopy reflectance (leaf area index, LAI). The GPP model estimates the effect of light and vegetation status, whereas the ER model captures the share of foliar biomass-dependent respiration and the ground water table. The sum of the study period (June–August 2016) GPP varied from -1301 to -670 g C m-2, ER from 632 to 1029 g C m-2 and net ecosystem exchange (NEE) from -322 to 68.5 g C m-2. NEE indicated a net sink of C in all plots except one with poor crop growth. The net ecosystem carbon balance (as the sum of NEE and carbon export as grains), indicated a net source of carbon in both plots with controlled drainage and a net sink in conventionally drained plots during the cultivation period. The greatest sink reported either as NEE or with the harvest included was the wettest plot, indicating that cereal production is possible in wetter than normal conditions.
Subjects/Keywords: peatland; CO2 flux modelling; ecosystem respiration; gross primary productivity; net ecosystem exchange; controlled drainage; groundwater table; Agroteknologia; Agrotechnology; Agroteknologi; peatland; CO2 flux modelling; ecosystem respiration; gross primary productivity; net ecosystem exchange; controlled drainage; groundwater table
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APA ·
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Manager
APA (6th Edition):
Karim, M. R. (2017). EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL. (Masters Thesis). University of Helsinki. Retrieved from http://hdl.handle.net/10138/228418
Chicago Manual of Style (16th Edition):
Karim, Md Rezaul. “EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL.” 2017. Masters Thesis, University of Helsinki. Accessed January 17, 2021.
http://hdl.handle.net/10138/228418.
MLA Handbook (7th Edition):
Karim, Md Rezaul. “EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL.” 2017. Web. 17 Jan 2021.
Vancouver:
Karim MR. EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL. [Internet] [Masters thesis]. University of Helsinki; 2017. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10138/228418.
Council of Science Editors:
Karim MR. EFFECT OF CONTROLLED DRAINAGE ON THE CARBON BALANCE OF A CULTIVATED PEAT SOIL. [Masters Thesis]. University of Helsinki; 2017. Available from: http://hdl.handle.net/10138/228418
University of Alabama
14.
Whelan, Andrew Walter.
Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems.
Degree: 2012, University of Alabama
URL: http://purl.lib.ua.edu/77784
► Fire regulates the structure and function of savanna ecosystems, yet we lack understanding of how cyclic fire affects savanna productivity and carbon dynamics. Furthermore, it…
(more)
▼ Fire regulates the structure and function of savanna ecosystems, yet we lack understanding of how cyclic fire affects savanna productivity and carbon dynamics. Furthermore, it is largely unknown how predicted changes in climate may impact the interaction between fire and carbon cycling in these systems. This study utilizes a novel combination of prescribed fire, eddy covariance (EC) and statistical techniques to investigate carbon dynamics in frequently burned longleaf pine savannas that lie along a gradient of soil moisture availability (mesic, intermediate and xeric). Results over three years of EC measurement of net
ecosystem exchange (NEE) show that the mesic site was a net carbon sink (NEE = -248.3 g C m^-2 yr^-1), while intermediate and xeric sites were net carbon sources (NEE = 157.5 and 146.2 g C m^-2 yr^-1, respectively), but when carbon losses due to fuel consumption were taken into account, all three sites were carbon sources (1077.9, 795.0 and 969.0 g C m^-2 yr^-1 at the mesic, intermediate and xeric sites, respectively). Nonetheless, rates of NEE returned to pre-fire levels 1-2 months following fire. Loss of leaf area drove the reduction in NEE following fire, but evolutionary adaptations to frequent fire allowed the
ecosystem to quickly recover carbon uptake capacity. While losses due to fire affected carbon balances, drought conditions over the final two years of the study were a more important factor driving net carbon loss during the study. In this work, we found that cyclic fire in pine savanna ecosystems maintains structure and carbon dynamics, but also that complex interactions between water availability,
ecosystem structure and fire influence carbon dynamics on multi-year timescales. Longer-term observations over greater environmental variability and multiple fire cycles and/or the development of process models would help to more precisely examine the complex interactions between fire and climate and make future prediction about carbon dynamics in these systems. (Published By University of Alabama Libraries)
Advisors/Committee Members: Starr, Gregory, Mitchell, Robert J., Mortazavi, Behzad, University of Alabama. Dept. of Biological Sciences.
Subjects/Keywords: Electronic Thesis or Dissertation; – thesis; Ecology; Biogeochemistry; Meteorology; ecosystem respiration (Reco); gross ecosystem exchange (GEE); longleaf pine; net ecosystem exchange (NEE); Pinus palustris; prescribed fire
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APA (6th Edition):
Whelan, A. W. (2012). Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/77784
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Whelan, Andrew Walter. “Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems.” 2012. Thesis, University of Alabama. Accessed January 17, 2021.
http://purl.lib.ua.edu/77784.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Whelan, Andrew Walter. “Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems.” 2012. Web. 17 Jan 2021.
Vancouver:
Whelan AW. Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems. [Internet] [Thesis]. University of Alabama; 2012. [cited 2021 Jan 17].
Available from: http://purl.lib.ua.edu/77784.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Whelan AW. Cyclic occurrence of fire and its role in carbon dynamics along an edaphic moisture gradient in longleaf pine ecosystems. [Thesis]. University of Alabama; 2012. Available from: http://purl.lib.ua.edu/77784
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Technical University of Lisbon
15.
Correia, Alexandra Cristina Pires.
Balanço de carbono em ecossistemas mediterrânicos.
Degree: 2013, Technical University of Lisbon
URL: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6153
► Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
Forests play an important role in climate change mitigation as they sequester…
(more)
▼ Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
Forests play an important role in climate change mitigation as they sequester and store carbon dioxide
(CO2) from the atmosphere. The aim of this thesis was to investigate forest carbon balance in its main
compartments: tress, understory and soils.
We present methods to estimate carbon stock in biomass of stone pine stands in south Portugal.
Allometric models, as well as conversion and expansion factors were presented allowing the
quantification of stand carbon stocks irrespective of the inventory base information available for the
site.
The undercanopy vegetation of a cork oak montado represented 20% of the total carbon assimilated by
the ecosystem during summer/autumn 2011. It was proven that the vegetation mosaic that naturally
colonized the understory have contrasting strategies to efficiently use the limited environmental
resources available like water and light.
Soil CO2 efflux, resulted from plants and microorganisms respiration, is similar between forests,
shrublands and grasslands. Soil moisture, more than temperature, is determinant in this process. We
present several empirical models, validated and calibrated using the Bayesian statistics, which allows
estimating monthly soil respiration in grasslands for the Mediterranean region.
Advisors/Committee Members: Pereira, João Santos.
Subjects/Keywords: carbon balance; Pinus pinea; allometric models; soil respiration; Bayesian statistic; Cistus; Ulex; eddy covariance; upscaling; Mediterranean ecosystem
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APA (6th Edition):
Correia, A. C. P. (2013). Balanço de carbono em ecossistemas mediterrânicos. (Thesis). Technical University of Lisbon. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6153
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Correia, Alexandra Cristina Pires. “Balanço de carbono em ecossistemas mediterrânicos.” 2013. Thesis, Technical University of Lisbon. Accessed January 17, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6153.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Correia, Alexandra Cristina Pires. “Balanço de carbono em ecossistemas mediterrânicos.” 2013. Web. 17 Jan 2021.
Vancouver:
Correia ACP. Balanço de carbono em ecossistemas mediterrânicos. [Internet] [Thesis]. Technical University of Lisbon; 2013. [cited 2021 Jan 17].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6153.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Correia ACP. Balanço de carbono em ecossistemas mediterrânicos. [Thesis]. Technical University of Lisbon; 2013. Available from: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6153
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Plymouth
16.
Calder-Potts, Ruth Naomi.
The biological and ecological impacts of hypoxia on coastal benthic communities.
Degree: PhD, 2017, University of Plymouth
URL: http://hdl.handle.net/10026.1/9352
► Traditionally, hypoxia has been defined as the situation where DO levels have fallen below 2.0 mg O2 L-1, but increasing evidence suggests that this low…
(more)
▼ Traditionally, hypoxia has been defined as the situation where DO levels have fallen below 2.0 mg O2 L-1, but increasing evidence suggests that this low level of DO is inadequate to describe the onset of hypoxia impacts for many organisms. Consequently, there is a need for a greater understanding of how ‘moderate’ alterations in DO levels will affect ecosystem processes and functionality, specifically through behavioural and physiological alterations at the organism and community level. This thesis reports on mesocosm experiments which were conducted to examine the effects of moderate ( > 3.0 mg O2 L-1) hypoxia on firstly, a key ecosystem engineer, the brittlestar Amphiura filiformis, and secondly, on the Station L4 infaunal macrobenthic community. Station L4 is a longstanding marine biodiversity and MSFD reference site and forms part of the Western Channel Observatory. At the organism level, short-term (14 d) exposure to moderate hypoxia significantly reduced oxygen uptake rates, oocyte diameter and oocyte development in A. filiformis. However, these physiological affects occurred irrespective of brittlestar population density. Additionally, moderate hypoxia reduced brittlestar activity, in terms of bioturbation behaviour, consequentially having an effect on ammonium and silicate fluxes. These observations were only detected when brittlestar population density was high. It was concluded that denser populations of A. filiformis may therefore exhibit the greatest changes in behaviour and shifts in ecosystem function as competition for resources and oxygen heightens. The benthic community at Station L4, displayed considerable tolerance to medium-term (6 wk.) exposure to moderate hypoxia, in terms of structure, diversity and bioturbatory behaviour, but these results may be different if exposure was longer or more severe. Alterations in nutrient fluxes were detected, but there was little evidence to suggest these changes were due to macrofaunal behavioural alterations. Additionally, results from this study revealed that bringing complex natural communities into the mesocosm caused a substantial loss of individuals and species, mainly due to translocation and disturbance effects. This important insight into the effects of bringing community assemblages into the mesocosm confirms that even with a loss of diversity, the L4 community maintained functionality and was resilient to alterations in DO. This suggests that the L4 benthic community does not depend on any one specific species for the provision of important ecosystem processes, resulting in considerable functional resilience within the L4 system. However, vulnerability to benthic systems may increase if functionality is dominated by species such as A. filiformis. Consequently, moderate hypoxia may not immediately affect benthic communities in terms of structure and diversity, but the physiological effects on individuals, especially to reproductive development, may cause alterations in the quality and quantity of planktonic propagules supplied by benthic species to the…
Subjects/Keywords: 578.77; hypoxia; low oxygen; bioturbation; invertebrate ecology; community response; global change; invertebrate biology; aerobic respiration; ecosystem processes
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APA (6th Edition):
Calder-Potts, R. N. (2017). The biological and ecological impacts of hypoxia on coastal benthic communities. (Doctoral Dissertation). University of Plymouth. Retrieved from http://hdl.handle.net/10026.1/9352
Chicago Manual of Style (16th Edition):
Calder-Potts, Ruth Naomi. “The biological and ecological impacts of hypoxia on coastal benthic communities.” 2017. Doctoral Dissertation, University of Plymouth. Accessed January 17, 2021.
http://hdl.handle.net/10026.1/9352.
MLA Handbook (7th Edition):
Calder-Potts, Ruth Naomi. “The biological and ecological impacts of hypoxia on coastal benthic communities.” 2017. Web. 17 Jan 2021.
Vancouver:
Calder-Potts RN. The biological and ecological impacts of hypoxia on coastal benthic communities. [Internet] [Doctoral dissertation]. University of Plymouth; 2017. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10026.1/9352.
Council of Science Editors:
Calder-Potts RN. The biological and ecological impacts of hypoxia on coastal benthic communities. [Doctoral Dissertation]. University of Plymouth; 2017. Available from: http://hdl.handle.net/10026.1/9352
Florida International University
17.
Moser, Jonathan G.
Cold Season Physiology of Arctic Plants.
Degree: MS, Biology, 2012, Florida International University
URL: https://digitalcommons.fiu.edu/etd/750
;
10.25148/etd.FI12113001
;
FI12113001
► The cold season in the Arctic extends over eight to nine months during which ecosystem gas exchange and water balance of arctic plants have…
(more)
▼ The cold season in the Arctic extends over eight to nine months during which
ecosystem gas exchange and water balance of arctic plants have been largely unexplored. The overall objective of this thesis was to examine two critical gaps in our knowledge about tundra cold season processes –
ecosystem respiration at very low temperatures and water uptake during the winter-spring transition. I determined the temperature response of
ecosystem respiration of tundra monoliths down to temperatures as low as can be expected under snow-covered conditions (-15 °C). Temperature responses fit the Arrhenius function well with Q
10 values over the range of -15 to 15 °C varying from 6.1 to 4.8. I used deuterium-enriched water (
2H
2O) as a tracer to evaluate water uptake of evergreen plants at snowmelt when soils are largely frozen. The results revealed that evergreen plants take up water under snow cover, possibly via roots but undoubtedly by foliar uptake.
Advisors/Committee Members: Steven F. Oberbauer, William T. Anderson, Jennifer H. Richards.
Subjects/Keywords: ecosystem respiration; carbon dioxide; water uptake; deuterium; stable isotope; Arctic; Alaska; tundra; cold season; low temperature; physiology
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APA (6th Edition):
Moser, J. G. (2012). Cold Season Physiology of Arctic Plants. (Thesis). Florida International University. Retrieved from https://digitalcommons.fiu.edu/etd/750 ; 10.25148/etd.FI12113001 ; FI12113001
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Moser, Jonathan G. “Cold Season Physiology of Arctic Plants.” 2012. Thesis, Florida International University. Accessed January 17, 2021.
https://digitalcommons.fiu.edu/etd/750 ; 10.25148/etd.FI12113001 ; FI12113001.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Moser, Jonathan G. “Cold Season Physiology of Arctic Plants.” 2012. Web. 17 Jan 2021.
Vancouver:
Moser JG. Cold Season Physiology of Arctic Plants. [Internet] [Thesis]. Florida International University; 2012. [cited 2021 Jan 17].
Available from: https://digitalcommons.fiu.edu/etd/750 ; 10.25148/etd.FI12113001 ; FI12113001.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Moser JG. Cold Season Physiology of Arctic Plants. [Thesis]. Florida International University; 2012. Available from: https://digitalcommons.fiu.edu/etd/750 ; 10.25148/etd.FI12113001 ; FI12113001
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
18.
López-Blanco, Efrén.
Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks.
Degree: PhD, 2018, University of Edinburgh
URL: http://hdl.handle.net/1842/33101
► The terrestrial CO2 exchange in the Arctic plays an important role in the global carbon (C) cycle. The Arctic ecosystems, containing a large amount of…
(more)
▼ The terrestrial CO2 exchange in the Arctic plays an important role in the global carbon (C) cycle. The Arctic ecosystems, containing a large amount of organic carbon (C), are experiencing ongoing warming in recent decades, which is affecting the C cycling and the feedback interactions between its different components. To improve our understanding of the atmosphere-ecosystem interactions, the Greenland Ecosystem Monitoring (GEM) program measures ecosystem CO2 exchange and links it to biogeochemical processes. However, this task remains challenging in northern latitudes due to an insufficient number of measurement sites, particularly covering full annual cycles, but also the frequent gaps in data affected by extreme conditions and remoteness. Combining ecosystem models and field observations we are able to study the underlying processes of Arctic CO2 exchange in changing environments. The overall aim of the research is to use data-model approaches to analyse the patterns of C exchange and their links to biological processes in Arctic ecosystems, studied in detail both from a measurement and a modelling perspective, but also from a local to a pan-arctic scale. In Paper I we found a compensatory response of photosynthesis (GPP) and ecosystem respiration (Reco), both highly sensitive to the meteorological drivers (i.e. temperatures and radiation) in Kobbefjord, West Greenland tundra. This tight relationship led to a relatively insensitive net ecosystem exchange (NEE) to the meteorology, despite the large variability in temperature and precipitations across growing seasons. This tundra ecosystem acted as a consistent sink of C (-30 g C m-2), except in 2011 (41 g C m-2), which was associated with a major pest outbreak. In Paper II we estimated this decrease of C sink strength of 118-144 g C m-2 in the anomalous year (2011), corresponding to 1210-1470 tonnes C at the Kobbefjord catchment scale. We concluded that the meteorological sensitivity of photosynthesis and respiration were similar, and hence compensatory, but we could not explain the causes. Therefore, in Paper III we used a calibrated and validated version of the Soil-Plant-Atmosphere model to explore full annual C cycles and detail the coupling between GPP and Reco. From this study we found two key results. First, similar metrological buffering to growing season reduced the full annual C sink strength by 60%. Second, plant traits control the compensatory effect observed (and estimated) between gross primary production and ecosystem respiration. Because a site-specific location is not representative of the entire Arctic, we further evaluated the pan-Arctic terrestrial C cycling using the CARDAMOM data assimilation system in Paper IV. Our estimates of C fluxes, pools and transit times are in good agreement with different sources of assimilated and independent data, both at pan-Arctic and local scale. Our benchmarking analysis with extensively used Global Vegetation Models (GVM) highlights that GVM modellers need to focus on the vegetation C dynamics, but also the…
Subjects/Keywords: 551.5; Greenland; Arctic; carbon cycle; net ecosystem exchange; photosynthesis; respiration; meteorology; biological disturbance; plant traits; observations; modelling
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
López-Blanco, E. (2018). Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/33101
Chicago Manual of Style (16th Edition):
López-Blanco, Efrén. “Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks.” 2018. Doctoral Dissertation, University of Edinburgh. Accessed January 17, 2021.
http://hdl.handle.net/1842/33101.
MLA Handbook (7th Edition):
López-Blanco, Efrén. “Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks.” 2018. Web. 17 Jan 2021.
Vancouver:
López-Blanco E. Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks. [Internet] [Doctoral dissertation]. University of Edinburgh; 2018. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1842/33101.
Council of Science Editors:
López-Blanco E. Ecosystem-atmosphere interactions in the Arctic : using data-model approaches to understand carbon cycle feedbacks. [Doctoral Dissertation]. University of Edinburgh; 2018. Available from: http://hdl.handle.net/1842/33101
Louisiana State University
19.
West, Jonathan L.
Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects.
Degree: PhD, Environmental Sciences, 2012, Louisiana State University
URL: etd-11132012-174953
;
https://digitalcommons.lsu.edu/gradschool_dissertations/109
► Since its introduction in 1956, the use of open-system, diel dissolved oxygen curves for estimating the components of ecosystem metabolism in the lotic setting have…
(more)
▼ Since its introduction in 1956, the use of open-system, diel dissolved oxygen curves for estimating the components of ecosystem metabolism in the lotic setting have been important in determining the current ecosystem theory of streams, both spatially among multiple systems and longitudinally within the same system, as well as identifying potentially impaired systems, especially when contrasted with streams considered unimpaired. Several factors have been identified as controls on both components of ecosystem metabolism and include light, nutrients, and stable substrates for gross primary production (GPP) and a source of organic matter (OM) for ecosystem respiration (ER). Stream size is important at mediating these factors through the presence or absence of a riparian canopy where small streams tend to have an intact canopy that can severely limit light to primary producers but provide a good source of OM for respiration. Alternatively, larger systems tend to lose canopy cover via widening of the stream and the limitation of light is relaxed while input of OM decreases. Additionally, inputs from watershed land use can affect GPP and ER in the stream via the inputs of nutrients to stimulate algal growth or organic pollution that stimulates heterotrophic activity. In the following studies, the effect of the presence or absence of a riparian canopy, watershed land use, and stochastic events such as flooding on ecosystem metabolism in coastal plain streams of southeast Louisiana are described. These systems behave similarly to previous studies and provide more evidence that the use of ecosystem metabolism as a metric for stream health is beneficial. Recommendations for future studies include the identification of more unimpaired systems while adding a temporal component, modeling systems under different hydrologic or climate change regimes, and the assessment of the impacts of stochastic events such as extreme weather events, exotic species invasions, or local extirpations of important species.
Subjects/Keywords: watershed land use; sediment stability; riparian canopy cover; nutrients; organic matter; ecosystem respiration; gross primary production; stream metabolism
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APA (6th Edition):
West, J. L. (2012). Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-11132012-174953 ; https://digitalcommons.lsu.edu/gradschool_dissertations/109
Chicago Manual of Style (16th Edition):
West, Jonathan L. “Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects.” 2012. Doctoral Dissertation, Louisiana State University. Accessed January 17, 2021.
etd-11132012-174953 ; https://digitalcommons.lsu.edu/gradschool_dissertations/109.
MLA Handbook (7th Edition):
West, Jonathan L. “Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects.” 2012. Web. 17 Jan 2021.
Vancouver:
West JL. Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects. [Internet] [Doctoral dissertation]. Louisiana State University; 2012. [cited 2021 Jan 17].
Available from: etd-11132012-174953 ; https://digitalcommons.lsu.edu/gradschool_dissertations/109.
Council of Science Editors:
West JL. Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects. [Doctoral Dissertation]. Louisiana State University; 2012. Available from: etd-11132012-174953 ; https://digitalcommons.lsu.edu/gradschool_dissertations/109
The Ohio State University
20.
Nietz, Jennifer Goedhart.
Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest.
Degree: MS, Evolution, Ecology and Organismal Biology, 2010, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1276543755
► The mixed deciduous forests of the upper Midwest, USA are approaching an ecological threshold in which early successional dominant aspen and birch trees are reaching…
(more)
▼ The mixed deciduous forests of the upper Midwest, USA
are approaching an ecological threshold in which early successional
dominant aspen and birch trees are reaching maturity and beginning
to senesce. At the University of Michigan Biological Station in
northern Michigan, we are combining long-term carbon (C) cycling
measurements with a large-scale experimental manipulation to
forecast how net
ecosystem production will change in response to
ongoing succession, disturbance, and climate variation. Our goal is
to elucidate biophysical mechanisms that will constrain C storage
in future forests. In the spring of 2008, we began the Forest
Accelerated Succession ExperimenT (FASET), in which all aspen and
birch (~35% canopy LAI) within 39 ha of an 85 yr old forest were
stem girdled to accelerate mortality. The adjacent, untreated
forest serves as a control. I hypothesized that, 1) aspen-birch
senescence would decrease C allocation to root and microbial pools,
resulting in increased root mortality and reduced root
respiration,
2) that the treatment effect on soil
respiration
(<i>R
s</i>) would become more
severe as time since girdling increased, and 3) the magnitude of
the treatment effect would be proportional to the percent basal
area of girdled aspen and birch. Sites with high percent basal area
of girdled aspen and birch would yield lower
<i>R
s</i>, while sites with low
percent basal area of girdled aspen and birch and control sites
would have higher <i>R
s</i>. We
measured <i>R
s</i> continuously
using arrays of automated soil
respiration chambers in the
treatment and control sites. We also quantified above and
below-canopy radiation, precipitation, air and soil temperature,
and soil moisture. At the
ecosystem scale, we calculated gross
primary production from measurements of net
CO
2 exchange between forest and atmosphere
using eddy-covariance methods. Soil
respiration was significantly
reduced in the treatment relative to the control site in the first
and second years after girdling, supporting my first hypothesis.
However, the treatment effect occurred faster than anticipated,
because root C stores were expected to maintain
<i>R
s</i> despite girdling in
the first treatment year. I modeled the automated chamber
<i>R
s</i> data using a
piece-wise linear regression and found that the magnitude of the
treatment effect was significantly greater in 2009 compared to
2008, supporting my second hypothesis. Results from the basal area
gradient study showed no significant difference between treatment
and control site <i>R
s</i>.
However, percent basal area of aspen and birch was a significant
explanatory parameter in the model, revealing that as percent basal
area of aspen and birch increased in the control site, so did
<i>R
s</i>. The treatment site
showed no relationship between
<i>R
s</i> and basal area,
suggesting the treatment is beginning to deteriorate normal forest
belowground functioning. My results provide an estimate…
Advisors/Committee Members: Curtis, Peter S. (Advisor).
Subjects/Keywords: Biogeochemistry; Forestry; soil; respiration; forest; carbon; ecosystem; girdling
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APA (6th Edition):
Nietz, J. G. (2010). Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1276543755
Chicago Manual of Style (16th Edition):
Nietz, Jennifer Goedhart. “Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest.” 2010. Masters Thesis, The Ohio State University. Accessed January 17, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1276543755.
MLA Handbook (7th Edition):
Nietz, Jennifer Goedhart. “Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest.” 2010. Web. 17 Jan 2021.
Vancouver:
Nietz JG. Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest. [Internet] [Masters thesis]. The Ohio State University; 2010. [cited 2021 Jan 17].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1276543755.
Council of Science Editors:
Nietz JG. Soil Respiration During Partial Canopy Senescence in a
Northern Mixed Deciduous Forest. [Masters Thesis]. The Ohio State University; 2010. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1276543755
University of St. Andrews
21.
Hambley, Graham.
The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
.
Degree: 2016, University of St. Andrews
URL: http://hdl.handle.net/10023/18563
► Northern peatlands play a critical role in the regulation of atmospheric carbon (C) and are estimated to store approximately 550 Gt C, which is around…
(more)
▼ Northern peatlands play a critical role in the regulation of atmospheric carbon (C) and are
estimated to store approximately 550 Gt C, which is around a quarter of the world soil C pool.
Saturated conditions means aboveground net primary productivity is low, but also results in low
decomposition and subsequently low respiratory losses. The Flow Country of Caithness and
Sutherland, Northern Scotland is the one of the largest areas of contiguous blanket bog in
Europe encompassing an area in excess of 4000 km². However, these peatlands were badly
degraded in the 1970s and 1980s by large-scale forestry plantations with around 17% of the
Flow Country drained and planted with Sitka spruce and Lodgepole pine altering net
ecosystem
C functioning. Restoration efforts have been on going since the 1990s to restore these sites to
blanket bog and return them to net C sinks. Using eddy covariance techniques this research
sought to understand C dynamics over two sites restored at different times, assess their C
sink/source status and the key environmental factors driving changes in C dynamics.
Results showed the youngest restoration site (Lonielist; restored in 2003/04) to be a net source
of C to the atmosphere of 80 g C m⁻² yr⁻¹, while the older restoration site (Talaheel; restored in
1997/98) was a net C sink of -71 g C m⁻² yr⁻¹. Partitioning of the net exchange into its
constituent parts of
respiration (R[sub](eco)) and photosynthesis (GPP) found significant differences in R[sub](eco) between the two sites, whilst no significant differences were observed in GPP. Soil
temperature and soil moisture were found to be the greatest controls on R[sub](eco), with higher R[sub](eco) associated with drier, warmer conditions. Incident solar radiation controlled GPP, however dry
periods coupled with high vapour pressure deficit resulted in a limitation of photosynthesis.
These results highlight that peatland restoration is successful at returning sites to net C sinks
over multi-decadal timescales.
Advisors/Committee Members: Wilson, Rob (advisor), Rinterknecht, Vincent (advisor).
Subjects/Keywords: Peatlands;
Peatland restoration;
Carbon;
Flow Country;
Net ecosystem exchange;
Respiration;
Photosynthesis;
Eddy covariance;
Northern Hemisphere;
Soil carbon
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Manager
APA (6th Edition):
Hambley, G. (2016). The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
. (Thesis). University of St. Andrews. Retrieved from http://hdl.handle.net/10023/18563
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hambley, Graham. “The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
.” 2016. Thesis, University of St. Andrews. Accessed January 17, 2021.
http://hdl.handle.net/10023/18563.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hambley, Graham. “The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
.” 2016. Web. 17 Jan 2021.
Vancouver:
Hambley G. The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
. [Internet] [Thesis]. University of St. Andrews; 2016. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10023/18563.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hambley G. The effect of forest-to-bog restoration on net ecosystem exchange in Flow Country peatlands
. [Thesis]. University of St. Andrews; 2016. Available from: http://hdl.handle.net/10023/18563
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
22.
Mezbahuddin, Mohammad.
Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen.
Degree: PhD, Department of Renewable Resources, 2015, University of Alberta
URL: https://era.library.ualberta.ca/files/c08612n671
► Peatlands have been accumulating carbon (C) in wet soils under shallow water table (WT) over millennia. Increased frequency and intensity of droughts and artificial drainage…
(more)
▼ Peatlands have been accumulating carbon (C) in wet
soils under shallow water table (WT) over millennia. Increased
frequency and intensity of droughts and artificial drainage for
promoting agriculture have recently been causing peatland WT depth
(WTD) drawdown. This could alter peatland C balance and shift
peatlands from net sinks to sources of C. To conserve the
resilience of these C stocks, improved predictive capacity is
required to forecast how these C stocks would be affected by
potentially deeper WT under future drier and warmer climates.
Process-based peatland eco-hydrology modelling could provide such
capacity. However, such modelling is thus far limited due to lack
of prognostic WTD dynamics and poor representation of WTD feedbacks
to peatland biogeochemistry. We aimed at using basic processes for
water and O2 transport and their effects on ecosystem water, C and
nutrient (nitrogen, phosphorus) cycling to model the effects of
seasonal and interannual variations of WTD on surface energy
exchange, water stress and net ecosystem CO2 exchange across
contrasting peatlands under variable weather conditions. For this
purpose we tested a process based ecosystem model ecosys under
contrasting precipitation in a tropical drained Indonesian bog from
a drier El-Niño year 2002 to a wetter year 2005 and in a boreal
pristine Western Canadian fen from a wetter year 2004 to a drier
year 2009. WTD was modelled from hydraulically-driven water
transfers controlled vertically by precipitation (P) vs.
evapotranspiration (ET), and laterally by discharge vs. recharge to
or from an external reference WTD (WTDx). These transfers caused
WTD drawdown and soil drying to be modelled during drier vs. wetter
seasons and years in the tropical peatland, which reduced ET and
caused plant water stress. WTD drawdown initially increased net
ecosystem productivity (NEP) in the tropical peatland by increasing
gross primary productivity (GPP) facilitated by improved plant
nutrient (phosphorus) availability and uptake due to rapid
mineralization in better aerated peats. This better aeration also
enhanced microbial O2 availability and energy yields that increased
ecosystem respiration (Re). When WT fell below a threshold of ~1.0
m below the hollow surface, increased Re along with reduced GPP
from plant water stress reduced NEP. Negative NEP modelled and
measured in this drained tropical peatland indicated that it was a
large C source. Our undrained model projection showed that this
peatland would have been a much smaller source of C had it not been
drained. Gradually declining P to ET ratio in the boreal fen
peatland caused WTD drawdown and peat drying from 2004 to 2009.
Reduction in lateral recharge and increase in lateral discharge
from the wettest to the driest year modelled from increasing WTDx
also contributed to this WTD drawdown simulating watershed-scale
drying effects on fen hydrology. When WT fell below a threshold of
~0.35 m below the hollow surface, intense drying of mosses caused
reduction in late growing season ecosystem ET. However,…
Subjects/Keywords: peatland C balance; ecosys; gross primary productivity; plant water relations; bogs and fens; CO2 exchange; water table depth; process based modelling; ecosystem respiration; net ecosystem productivity; eco-hydrology
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APA (6th Edition):
Mezbahuddin, M. (2015). Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/c08612n671
Chicago Manual of Style (16th Edition):
Mezbahuddin, Mohammad. “Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen.” 2015. Doctoral Dissertation, University of Alberta. Accessed January 17, 2021.
https://era.library.ualberta.ca/files/c08612n671.
MLA Handbook (7th Edition):
Mezbahuddin, Mohammad. “Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen.” 2015. Web. 17 Jan 2021.
Vancouver:
Mezbahuddin M. Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen. [Internet] [Doctoral dissertation]. University of Alberta; 2015. [cited 2021 Jan 17].
Available from: https://era.library.ualberta.ca/files/c08612n671.
Council of Science Editors:
Mezbahuddin M. Modelling water table depth effects on net ecosystem CO2
exchange of two contrasting forested peatlands – a tropical bog and
a boreal fen. [Doctoral Dissertation]. University of Alberta; 2015. Available from: https://era.library.ualberta.ca/files/c08612n671
University of Toledo
23.
Chu, Housen.
Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems.
Degree: PhD, College of Natural Sciences and
Mathematics, 2014, University of Toledo
URL: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418393261
► Severe weather and climate anomalies have been observed increasingly in recent decades in United States. Large uncertainties still exist about to what extent ecosystems may…
(more)
▼ Severe weather and climate anomalies have been
observed increasingly in recent decades in United States. Large
uncertainties still exist about to what extent ecosystems may
respond to such drastic variability of external environmental
forcing in terms of their carbon sequestration rates. Challenges
also remain in predicting and assessing the potential impact of
climate variability and anomaly under anticipated climate change.
This study targeted the three most prevalent ecosystems (i.e., a
deciduous woodland, a conventional cropland, and a coastal
freshwater marsh) in northwestern Ohio, USA. Using the eddy
covariance method and supplementary measurements, I examined the
effects of recent climatic variability and anomalies (2011-2013) on
ecosystem carbon fluxes (i.e., net
ecosystem
CO
2/CH
4 exchanges
(F
CO2/F
CH4) and
lateral hydrologic fluxes of dissolved organic carbon
(F
DOC), particulate organic carbon
(F
POC), and dissolve inorganic carbon
(F
DIC)). Gross
ecosystem production (GEP)
and
ecosystem respiration (ER) were the two largest fluxes in the
annual carbon budget at all three ecosystems. Yet, these two fluxes
compensated each other to a large extent and their balance –
F
CO2 – depended largely on the interannual
variability of these two large fluxes. Around 57-58%, 91-96%, and
77-78% of the interannual F
CO2 variability
was attributed to functional changes of ecosystems among years,
suggesting that the changes of
ecosystem structural, physiological,
or phenological characteristics played an important role in
regulating interannual variability of GEP, ER and
F
CO2. Freshwater marshes deserve more
research attention for their high F
CH4
(~50.8±1.0 g C m
-2
yr
-1) and lateral hydrologic carbon
inflows/outflows. Lateral hydrologic flows were an important vector
in re-locating carbon among ecosystems in the region. Considerable
hydrologic carbon flowed both into and out of the research marsh
(108.3±5.4 and 86.2±10.5 g C m
-2
yr
-1, respectively). Despite marshes
accounting for only ~4% of area in this agriculture-dominated
landscape, they are potentially efficient in turning over and
releasing newly fixed carbon (allochthonous and autochthonous) as
CH
4 and should be carefully addressed in the
regional carbon budget. In sum, this study highlights that
different carbon fluxes respond unequally and even oppositely to
climate variability and anomaly and thus, their balances may vary
largely among ecosystems and years.
Advisors/Committee Members: Chen, Jiquan (Advisor), Gottgens, Johan (Advisor).
Subjects/Keywords: Environmental Science; Ecology; Eddy covariance; methane; freshwater marsh; cropland; carbon budget, carbon dioxide, dissolved organic carbon,
particulate organic carbon, carbon sequestration; gross ecosystem production; ecosystem respiration; interannual variability; climate anomaly
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Manager
APA (6th Edition):
Chu, H. (2014). Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems. (Doctoral Dissertation). University of Toledo. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418393261
Chicago Manual of Style (16th Edition):
Chu, Housen. “Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems.” 2014. Doctoral Dissertation, University of Toledo. Accessed January 17, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418393261.
MLA Handbook (7th Edition):
Chu, Housen. “Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems.” 2014. Web. 17 Jan 2021.
Vancouver:
Chu H. Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems. [Internet] [Doctoral dissertation]. University of Toledo; 2014. [cited 2021 Jan 17].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418393261.
Council of Science Editors:
Chu H. Response and Biophysical Regulation of Carbon Fluxes to
Climate Variability and Anomaly in Contrasting Ecosystems. [Doctoral Dissertation]. University of Toledo; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418393261
24.
Fouché, Julien.
Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada.
Degree: Docteur es, Géosciences de l'environnement, 2014, Aix-Marseille; Université Laval (Québec, Canada)
URL: http://www.theses.fr/2014AIXM4306
► L'augmentation de la décomposition de la matière organique des cryosols arctiques sous l'effet du réchauffement et de la dégradation du pergélisol contribuerait à une rétroaction…
(more)
▼ L'augmentation de la décomposition de la matière organique des cryosols arctiques sous l'effet du réchauffement et de la dégradation du pergélisol contribuerait à une rétroaction positive sur les changements climatiques. Nous étudions le fonctionnement biogéochimique de deux Cryosols: un cryosol histique (H) et un cryosol turbique (T), en conditions naturelles et réchauffés. Les profils ont été instrumentés à Salluit (Nunavik, Canada) et les mesures ont été faites pendant les étés 2010 et 2011. Le réchauffement augmente la respiration de l'écosystème (ER) de manière plus intense pour H que pour T, bien que ER pour H soit plus faible. La sensibilité thermique de ER (Q10) est supérieure pour T que pour H et diminue avec le réchauffement. L'étude montre que les cycles journaliers de ER en fonction de la temperature forment des hystérésis. La variance de ER est mieux expliquée en utilisant la température minimale de la journée et la profondeur du front de dégel pour H. Pour T, l'ajout de la vitesse du vent et la radiation solaire améliore l'explication de la variance de ER. Nous montrons trois dynamiques spécifiques aux écosystèmes nordiques: 1) ER dépendant des propriétés du sol et de la solution du sol ; 2) rôle de variables thermo-indépendantes sur ER et 3) variations journalières du Q10 et interannuelles de la respiration basale. La décomposition de la matière organique est la principale source de CO2 pour H alors que les processus végétaux contrôlent ER pour T. Nos résultats contribuent à la compréhension et à l'extrapolation des mesures ponctuelles dans les écosystèmes de toundra, améliorant ainsi la modélisation du cycle du carbone dans les cryosols.
Increased organic mater decomposition rate in Arctic Cryosols due to warming and to permafrost thawing can lead to the release of greenhouse gases, thus potentially creating a positive feedback on climate change. We studied the biogeochemical functioning of two different permafrost-affected soils (i.e. Cryosols): a Histic Cryosol (H) and a Turbic Cryosol (T), both in natural conditions and under an experimental warming. Profiles were instrumented in Salluit (Nunavik, Canada) and monitored during summers 2010 and 2011. The induced warming increased CO2 fluxes in both soils; this impact was however more striking at H even if ER was lower than at T. Temperature sensitivity of ER (Q10) was higher at T than at H and decreased both with warming. We highlighted that diurnal ER cycles as a function of temperature showed hysteretic loops. Linear models performed to explain ER variance were improved adding daily minimum temperature and thaw front depth at H. In contrast at T, adding wind speed and solar radiation in models improved the ER variance explanation. We showed three specific CO2 flux dynamics related to northern ecosystems: 1) the large difference of ER depending on soil properties and soil solution composition; 2) environmental variables strongly alter CO2 fluxes and 3) the diurnal Q10 variations and the inter annual variability of basal respiration. Our results…
Advisors/Committee Members: Keller, Catherine (thesis director), Allard, Michel (thesis director), Ambrosi, Jean-Paul (thesis director).
Subjects/Keywords: Cryosol histique et turbique; Modélisation thermique; Teneur en eau volumique; Toundra; Réchauffement expérimental; Respiration de l'écosystème; Solution du sol; Pergélisol arctique; Décomposition de la matière organique; Respiration dérivée de la végétation; Histic and Turbic Cryosol; Thermal modeling; Volumetric water content; Tundra; Experimental warming; Ecosystem respiration; Soil solution; Arctic permafrost; Organic matter decomposition; Plant-Derived respiration
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APA ·
Chicago ·
MLA ·
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CSE |
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fouché, J. (2014). Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada. (Doctoral Dissertation). Aix-Marseille; Université Laval (Québec, Canada). Retrieved from http://www.theses.fr/2014AIXM4306
Chicago Manual of Style (16th Edition):
Fouché, Julien. “Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada.” 2014. Doctoral Dissertation, Aix-Marseille; Université Laval (Québec, Canada). Accessed January 17, 2021.
http://www.theses.fr/2014AIXM4306.
MLA Handbook (7th Edition):
Fouché, Julien. “Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada.” 2014. Web. 17 Jan 2021.
Vancouver:
Fouché J. Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada. [Internet] [Doctoral dissertation]. Aix-Marseille; Université Laval (Québec, Canada); 2014. [cited 2021 Jan 17].
Available from: http://www.theses.fr/2014AIXM4306.
Council of Science Editors:
Fouché J. Effet du réchauffement climatique sur le fonctionnement biogéochimique de deux cryosols arctiques dans la région de Salluit, Nunavik, Canada : Global warming impacts on the biogeochemical functioning of two arctic cryosols in the Salluit region, Nunavik, Canada. [Doctoral Dissertation]. Aix-Marseille; Université Laval (Québec, Canada); 2014. Available from: http://www.theses.fr/2014AIXM4306
University of Waterloo
25.
Venkiteswaran, Jason James.
Greenhouse gas cycling in experimental boreal reservoirs.
Degree: 2009, University of Waterloo
URL: http://hdl.handle.net/10012/4168
► Hydroelectric reservoirs account for 59% of the installed electricity generating capacity in Canada and 26% in Ontario. Reservoirs also provide irrigation capacity, drinking water, and…
(more)
▼ Hydroelectric reservoirs account for 59% of the installed electricity generating capacity in Canada and 26% in Ontario. Reservoirs also provide irrigation capacity, drinking water, and recreational opportunities. Further, they continue to be built in northern Canada, neighbouring boreal countries, and around the world. Yet given their socio-economic importance, they are understudied with respect to greenhouse gas emissions, nutrient and mercury cycling, and aquatic metabolism.
As one of many electricity generating options, hydroelectricity is viewed as well-tested because of its long history and diverse applications in mega-projects, run-of-the-river dams, and small, local applications. It is also considered renewable from a fuel stand-point because an adequate long-term supply of water is assumed. One of several significant criticisms of hydroelectric development is that reservoirs may be a significant source of greenhouse gases to the atmosphere relative to the amount of electricity produced due to flooding the landscape.
As a result of the dearth of information on reservoir development and both greenhouse gases and aquatic metabolism, a pair of whole-ecosystem reservoir experiments were conducted staring in 1991. Three upland boreal forest reservoirs with differing amounts of pre-flood stored organic carbon were built in northwestern Ontario and flooded for five years. The rates of net greenhouse gas production in these reservoirs were determined by calculating mass budgets for carbon dioxide and methane. Additionally, rates of biological processes were determined by combining the mass budgets with measurements of the stable isotopes of carbon and oxygen.
Assembling mass and isotope-mass budgets required three related projects on gas exchange, methane oxidation, and oxygen isotopes. To estimate the gas exchange coefficient for each of the upland reservoirs, a comparative-methods study was undertaken. Methane oxidation enrichment factors were determined in upland and wetland boreal reservoirs so that the importance of methane oxidation in these ecosystems could be assessed. In order to interpret the diel changes in both oxygen concentrations and their isotopic ratios, a dynamic model was developed. This model, PoRGy, was successfully applied to the upland boreal reservoirs as well as prairie rivers and ponds. Further, PoRGy was used to understand the interplay between the key parameters that control oxygen concentrations, to compare aquatic ecosystems, to make quantitative estimates of ecosystem metabolism, and to assess the vulnerability of aquatic ecosystems under various environmental stressors.
Carbon isotope-mass budgets were used to conclude that community respiration rates declined quickly in the upland reservoirs and had declined by half over five years. This suggested that the most labile organic carbon is quickly consumed but decomposition continued for the five-year life of the project. Net primary production rates were similar for three years, with a small peak in the second or third year,…
Subjects/Keywords: hydroelectric reservoirs; stable isotopes; community respiration; primary production; whole-ecosystem experiment; catchment-scale
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APA (6th Edition):
Venkiteswaran, J. J. (2009). Greenhouse gas cycling in experimental boreal reservoirs. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/4168
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Venkiteswaran, Jason James. “Greenhouse gas cycling in experimental boreal reservoirs.” 2009. Thesis, University of Waterloo. Accessed January 17, 2021.
http://hdl.handle.net/10012/4168.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Venkiteswaran, Jason James. “Greenhouse gas cycling in experimental boreal reservoirs.” 2009. Web. 17 Jan 2021.
Vancouver:
Venkiteswaran JJ. Greenhouse gas cycling in experimental boreal reservoirs. [Internet] [Thesis]. University of Waterloo; 2009. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10012/4168.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Venkiteswaran JJ. Greenhouse gas cycling in experimental boreal reservoirs. [Thesis]. University of Waterloo; 2009. Available from: http://hdl.handle.net/10012/4168
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Macquarie University
26.
Barneche Rosado, Diego.
Scaling fish energetics from individuals to communities.
Degree: 2015, Macquarie University
URL: http://hdl.handle.net/1959.14/1057109
► Theoretical thesis.
Bibliography: pages 189-191.
Introduction – Chapter 1. Scaling metabolism from individuals to reef-fish communities at broad spatial scales – Chapter 2. Energetic and…
(more)
▼ Theoretical thesis.
Bibliography: pages 189-191.
Introduction – Chapter 1. Scaling metabolism from individuals to reef-fish communities at broad spatial scales – Chapter 2. Energetic and ecological constraints on population density – Chapter 3. Quantifying the energetics of fish growth and its implications for energy transfer between trophic levels – Synthesis – Appendices.
Two distinct biological currencies - energy and materials - are essential to life because both are required for the maintenance, growth and reproduction of organisms. Modelling ecological phenomena on the basis of these currencies therefore holds potential for developing a deeper understanding of how the availability of energy and materials in the environment constrains life, in all its diversity, across space and time. In this dissertation, I use the Metabolic Theory of Ecology (MTE) as a framework to explore how individual energetics influences biological processes at distinct levels of organization, from individuals to communities. Particularly, I explore how body mass, environmental temperature, and other variables constrain (i) metabolic rates and growth rates of individuals, and thereby influence (ii) densities of populations at different trophic levels and (iii) the standing biomass and energy fluxes of communities that differ substantially in species diversity. I use fishes to address these questions because they encompass the highest species richness among vertebrates, they encompass more than seven orders of magnitude in body mass, and they occupy diverse habitats that vary substantially in thermal regime across the globe. At the individual level, MTE predictions are generally well supported, although deviations attributable to differences among taxa are clearly noted. By contrast, at the population and community levels, while I do find evidence of energetic constraints, deviations from MTE-derived predictions are frequently observed, highlighting the importance of factors other than individual energetics. I conclude by discussing the implications of these findings to climate change biology and ecosystem dynamics, and highlight avenues for future research.
Access via World Wide Web.
1 online resource (191 pages) illustrations (some coloured)
Advisors/Committee Members: Macquarie University. Department of Biological Sciences.
Subjects/Keywords: Fishes – Ecology; Fishes – Development; Systems biology; Coral reef fishes – Ecology; Populations biology; metabolic theory of ecology; population; ecosystem; respiration; carbon cycle; energy; efficiency; coral reefs
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APA ·
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Manager
APA (6th Edition):
Barneche Rosado, D. (2015). Scaling fish energetics from individuals to communities. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1057109
Chicago Manual of Style (16th Edition):
Barneche Rosado, Diego. “Scaling fish energetics from individuals to communities.” 2015. Doctoral Dissertation, Macquarie University. Accessed January 17, 2021.
http://hdl.handle.net/1959.14/1057109.
MLA Handbook (7th Edition):
Barneche Rosado, Diego. “Scaling fish energetics from individuals to communities.” 2015. Web. 17 Jan 2021.
Vancouver:
Barneche Rosado D. Scaling fish energetics from individuals to communities. [Internet] [Doctoral dissertation]. Macquarie University; 2015. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1959.14/1057109.
Council of Science Editors:
Barneche Rosado D. Scaling fish energetics from individuals to communities. [Doctoral Dissertation]. Macquarie University; 2015. Available from: http://hdl.handle.net/1959.14/1057109
University of Georgia
27.
Manning, David William Pierce.
Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams.
Degree: 2016, University of Georgia
URL: http://hdl.handle.net/10724/35417"
► Human activities such as agriculture and urbanization result in mobilization of nitrogen (N) and phosphorus (P) to aquatic ecosystems. Despite increased availability of both N…
(more)
▼ Human activities such as agriculture and urbanization result in mobilization of nitrogen (N) and phosphorus (P) to aquatic ecosystems. Despite increased availability of both N and P, little is known about the relative importance of N vs. P
on detrital carbon (C) loss rates, or the combined effects of N, P and increased temperature or dissolved organic C (DOC) due to land use or climate change. Here, we focused on how N and P controls detrital C loss rates mediated by microbial decomposers
and/or detritivores, and the interactive effects of elevated nutrients, temperature and DOC. To test N vs. P effects on detrital C, five streams were experimentally enriched with crossed N and P concentration gradients and ratios of N:P. I examined
naturally occurring detritus (leaf litter, wood, and fine particles), and deployed detrital resources (four leaf species and wood veneers) across seasonal temperature gradients, and determined how increased N and P altered microbial and detritivore
biomass, resource stoichiometry (C:nutrient content), respiration and breakdown rates. I used nutrient and DOC additions to stream mesocosms to determine their effects on detrital C loss. Breakdown and respiration rates of coarse detrital substrates
increased with elevated nutrients and temperature; the largest response to nutrients was for breakdown rates (~2.8× higher with nutrients), followed by respiration (1.5× higher with nutrients, or seasonal temperature). DOC had negligible effects on
respiration or litter decomposition. Nutrient enrichment increased nutrient content (reduced C:N, C:P) of all detritus types; nutrient-poor detritus tended to decrease the most, such that detrital stoichiometry converged during decay. Nutrient effects on
detrital C:nutrient stoichiometry were critical predictors of increased detrital C loss rates, and detritivore biomass. These data suggest that N and P enrichment predictably increases detrital C loss rates, and that nutrient-altered detrital
stoichiometry is a critical mechanism for predicting the occurrence of increased detrital C loss from streams. Mitigating excessive nutrient pollution is a key management goal for streams, and these studies imply that detrital stoichiometry could be used
as an integrative measure of nutrient pollution and its effects on a key ecosystem function that is currently overlooked in nutrient management policies.
Subjects/Keywords: Ecosystem; Coweeta; Ecological stoichiometry; Heterotrophic; Nutrients; Detritus; Detritivores; Leaf litter; Wood; Fine benthic organic matter; Dissolved organic carbon; Microbial Respiration; Fungal biomass; Threshold elemental ratio.
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APA ·
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Manager
APA (6th Edition):
Manning, D. W. P. (2016). Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/35417"
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Manning, David William Pierce. “Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams.” 2016. Thesis, University of Georgia. Accessed January 17, 2021.
http://hdl.handle.net/10724/35417".
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Manning, David William Pierce. “Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams.” 2016. Web. 17 Jan 2021.
Vancouver:
Manning DWP. Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams. [Internet] [Thesis]. University of Georgia; 2016. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10724/35417".
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Manning DWP. Linking the effects of nitrogen and phosphorus enrichment to controls of detrital carbon loss rates from streams. [Thesis]. University of Georgia; 2016. Available from: http://hdl.handle.net/10724/35417"
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
28.
Flynn, Conor R.
Soil Respiration Response to Disturbance in a Northern
Michigan Forest.
Degree: MS, Environment and Natural Resources, 2012, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1336919672
► Carbon storage in eastern U.S. forests is threatened by stem-girdling invasive insects, along with natural succession as pioneer tree species age and die. In Northern…
(more)
▼ Carbon storage in eastern U.S. forests is threatened
by stem-girdling invasive insects, along with natural succession as
pioneer tree species age and die. In Northern lower Michigan we are
investigating the impact of these intermediate disturbances on
above- and below-ground carbon cycling across a mixed hardwood and
pine forest. In spring 2008, early successional tree species, such
as aspen (Populus grandidenta and P. tremuloides), were
experimentally girdled in the Forest Accelerated Succession
Experiment (FASET), while a nearby long-term research site,
Ameriflux (AF), remained undisturbed. Soil
respiration (Rs) is
known to be responsive to disturbance and comprises the largest
fraction of total
ecosystem respiration (Re). However, determining
effects of management on Rs is complicated by difficulties
accurately measuring temporal variability in soil
respiration and
biophysical controlling factors such as soil temperature and soil
water content (SWC). The objective of this study was to quantify Rs
(soil CO2 efflux) and its constraints and drivers in disturbed and
undisturbed forests and under early successional and late
successional tree species. Rs, temperature, and SWC were
intensively measured at four instrumented sites and extensively
measured across the landscape along a number of 1km transects. A
nested study design featured paired sites under early- and
late-successional tree canopies (aspen and oak) in disturbed and
undisturbed forest (FASET and AF). Rs was measured every hourly at
the soil pits using an automated closed-chamber CO2 efflux system
and biweekly along the 1km transects using a portable
closed-chamber CO2 efflux system. Rs decreased under the canopy of
disturbed aspen trees compared to controls aspen trees but was
unchanged under the canopy of disturbed oak trees compared to
control oak trees. Temperature sensitivity of Rs, as measured by a
Q10 analysis, decreased under both aspen and oak trees in the
disturbed forest compared to the control forest, indicating a
possible decoupling between biophysical drivers and Rs following
disturbance. A wavelet coherence analysis showed time-varying
patterns of Rs responses to temperature and moisture, allowing
inspection of diurnal Rs hysteresis as well as large effluxes
associated with intermittent precipitation events. The results of
this study show that further research is needed on the underlying
mechanisms that control soil
respiration and ultimately the C cycle
of disturbed forest ecosystems.
Advisors/Committee Members: Curtis, Peter (Committee Chair).
Subjects/Keywords: Ecology; soil respiration; ecosystem; succession; soil; carbon cycle
…soil respiration cuvette
N= Nitrogen
NEE= Net Ecosystem Exchange
NPP= Net Primary… …Productivity
PAR= Photosynthetically Active Radiation
Ra= Autotrophic Soil Respiration
Re= Ecosystem… …ecosystem Gross Primary Production (GPP) minus Ecosystem Respiration (Re)… …ecosystem respiration
and adds approximately 10 times more carbon to the atmosphere than… …Respiration
Rh= Heterotrophic Soil Respiration
Rs= Soil Respiration
SWC= Soil Water content (…
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APA (6th Edition):
Flynn, C. R. (2012). Soil Respiration Response to Disturbance in a Northern
Michigan Forest. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1336919672
Chicago Manual of Style (16th Edition):
Flynn, Conor R. “Soil Respiration Response to Disturbance in a Northern
Michigan Forest.” 2012. Masters Thesis, The Ohio State University. Accessed January 17, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1336919672.
MLA Handbook (7th Edition):
Flynn, Conor R. “Soil Respiration Response to Disturbance in a Northern
Michigan Forest.” 2012. Web. 17 Jan 2021.
Vancouver:
Flynn CR. Soil Respiration Response to Disturbance in a Northern
Michigan Forest. [Internet] [Masters thesis]. The Ohio State University; 2012. [cited 2021 Jan 17].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1336919672.
Council of Science Editors:
Flynn CR. Soil Respiration Response to Disturbance in a Northern
Michigan Forest. [Masters Thesis]. The Ohio State University; 2012. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1336919672
29.
Allen, Jordan.
Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The.
Degree: MS(M.S.), Ecology, 2016, Colorado State University
URL: http://hdl.handle.net/10217/178853
► Anthropogenic activities contribute to increased levels of nitrogen deposition and elevated CO2 concentrations in terrestrial ecosystems. The response of soil respiration to nitrogen fertilization in…
(more)
▼ Anthropogenic activities contribute to increased levels of nitrogen deposition and elevated CO2 concentrations in terrestrial ecosystems. The response of soil
respiration to nitrogen fertilization in an on going 18- year field nitrogen amendment study was conducted from July 2014 to October 2014. The focus of this study was to determine the effects of nitrogen fertilization on soil carbon cycling, via
respiration. Our objectives were to (1) test the hypothesis that N additions would increase soil
respiration in Rocky Mountain National Park, and (2) understand the impacts of N additions on carbon flows in subalpine forests. A LiCor LI-820 infrared gas analyzer (IRGA) was used to quantify soil
respiration rates. We compared soil
respiration from fertilized forest plots (30 x 30 m) with soil
respiration from control forests plots (30 x 30 m) that receive only ambient nitrogen deposition (3-5 kg/ N/ha-1/yr-1) during the 2014-growing season. Our results shows that mean soil
respiration measurements were not significantly different in the control plots (3.14 µmol m-2 sec-1) than in the fertilized plots (3.02 µmol m-2 sec-1). Treatment was insignificant in influencing soil
respiration (p-value greater than 0.5), allowing us to reject our primary hypothesis: that nitrogen additions would lead to an increase in soil
respiration. Our results confirm previous research in these plots Advani (2004). The statistically identical soil
respiration rates between the control and fertilized plots may result from nitrogen saturation due to elevated levels of ambient N deposition, microbial suppression due to very high levels of N additions in the fertilized plots, or some combination of the two.
Advisors/Committee Members: Denning, A. Scott (advisor), Baron, Jill (advisor), Ryan, Mike (committee member), Bowser, Gillian (committee member).
Subjects/Keywords: climate change; fertilization; soil respiration; ecosystem; carbon dioxide; nitrogen deposition
…respiration will help us understand the impacts of forest ecosystem response to N deposition.
To… …components of ecosystem respiration. It
is linked to photosynthesis, litter fall and plant… …led to changes in ecosystem properties C: N ratios in soils and lake uptake of nitrogen… …respiration. In
addition, root respiration should respond to N additions as a consequence of greater… …leading to decreased soil respiration (Bowden et al., 2004; Burton et
al., & 2004; Frey et…
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APA ·
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MLA ·
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CSE |
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Manager
APA (6th Edition):
Allen, J. (2016). Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/178853
Chicago Manual of Style (16th Edition):
Allen, Jordan. “Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The.” 2016. Masters Thesis, Colorado State University. Accessed January 17, 2021.
http://hdl.handle.net/10217/178853.
MLA Handbook (7th Edition):
Allen, Jordan. “Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The.” 2016. Web. 17 Jan 2021.
Vancouver:
Allen J. Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The. [Internet] [Masters thesis]. Colorado State University; 2016. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/10217/178853.
Council of Science Editors:
Allen J. Effects of long term nitrogen fertilization on forest soil respiration in a subalpine ecosystem in Rocky Mountain National Park, The. [Masters Thesis]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/178853
30.
Sharkhuu, Anarmaa.
Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia.
Degree: 2012, University of Pennsylvania
URL: https://repository.upenn.edu/edissertations/695
► Northern Mongolia currently sequesters 31 Tg C yr-1 but it may become a carbon source if respiration rates increase due to climate change and overgrazing,…
(more)
▼ Northern Mongolia currently sequesters 31 Tg C yr-1 but it may become a carbon source if respiration rates increase due to climate change and overgrazing, or if projected boundary shifts between forest and steppe cause a change in the carbon storage of ecosystems. The objectives of the thesis are to study soil ecosystem response to simulated climate change and grazing, and to assess C stocks in the steppe and forest. Open-top chambers (OTCs) have been frequently used for simulating climate change. However, the pattern of temperature increase by OTCs contradicted the IPCC predictions. An alternative method, open-sided chambers (OSCs), was evaluated based on its effects on abiotic and biotic factors. The results indicated that OSCs manipulated air temperature in a pattern that was predicted by IPCC models, but the overall effect was too small, hence it is not an optimal device. In the subsequent study, OTCs were used to study soil respiration response to experimental warming in three ecosystems. Temperature increase by OTCs had no effect on soil respiration in the steppe but increased soil respiration in the forest (by 0.20 g CO2 m-2 h-1), demonstrating the importance of ecosystem setting. Although warming increased soil respiration, it decreased its temperature sensitivity as well (Q10 = 5.82 in control versus 2.22 in OTC). In addition to OTCs, watering and grazing effects on CO2 effluxes (ecosystem and soil respiration) were studied across the topographical gradients in the steppe. Our results show a robust, positive effect of soil moisture on CO2 effluxes across topography, and the contrasting effects of grazing on CO2 effluxes. Interactive effects of the treatments were minimal. Soil carbon of the forest was the same (8.3 kg C m-2) as the steppe (8.1 kg C m-2) but aboveground carbon in the forest (2.9 kg C m-2) was 3-7 times greater than that in the steppe. In summary, the results show that warming will slightly increase soil respiration in the forest, but in steppe precipitation will have stronger effect on CO2 flux than temperature change. The results also indicated that overgrazing and deforestation could trigger a greater loss of carbon
Subjects/Keywords: Ecosystem respiration; Grazing; Mongolia; Soil carbon; Soil respiration; Warming; Biogeochemistry; Ecology and Evolutionary Biology; Environmental Sciences
…ecosystem setting.
Although warming increased soil respiration, it decreased its temperature… …watering and grazing
effects on CO2 effluxes (ecosystem and soil respiration) were… …2
3.
Soil and ecosystem respiration responses to climate change simulations… …92
3.3.3.
Ecosystem respiration… …by the rate of
photosynthesis and ecosystem respiration that consists of aboveground (…
Record Details
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APA ·
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MLA ·
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APA (6th Edition):
Sharkhuu, A. (2012). Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/695
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sharkhuu, Anarmaa. “Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia.” 2012. Thesis, University of Pennsylvania. Accessed January 17, 2021.
https://repository.upenn.edu/edissertations/695.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sharkhuu, Anarmaa. “Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia.” 2012. Web. 17 Jan 2021.
Vancouver:
Sharkhuu A. Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia. [Internet] [Thesis]. University of Pennsylvania; 2012. [cited 2021 Jan 17].
Available from: https://repository.upenn.edu/edissertations/695.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sharkhuu A. Soil Ecosystem Responses to Climate Change and Land-Use Simulations and Estimation of Carbon Stocks in Steppe and Forest Ecosystems in Northern Mongolia. [Thesis]. University of Pennsylvania; 2012. Available from: https://repository.upenn.edu/edissertations/695
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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Open Access Theses and Dissertations
