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You searched for subject:( Fog AND dew precipitation). Showing records 1 – 3 of 3 total matches.

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University of the Western Cape

1. Maphangwa, Khumbudzo Walter. Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem .

Degree: 2010, University of the Western Cape

Elevated temperatures accompanying climate warming are expected to have adverse effects on sensitive lichen species. This premise was examined by measuring the sensitivity of different lichen species to elevated temperatures in the laboratory and in the field. Laboratory studies involved the exposure of nine hydrated lichen species (Xanthoparmelia austro-africana, X. hyporhytida, Xanthoparmelia sp., Xanthomaculina hottentotta, Teloschistes capensis, Ramalina sp., Flavopuntelia caperata, Lasallia papulosa, Parmotrema austrosinensis) collected from sites of different aridity and mean annual temperature for 2 hourly intervals to temperatures ranging from 24ºC to 48ºC in a forced daft oven and measuring their respiration rates and maximum quantum yield of PSII. Field studies involved simultaneous hourly measurements of ground surface air temperatures and Lichen effective quantum yield of PSII of hydrated lichen species populations under ambient and artificially modified environmental conditions. Advisors/Committee Members: Musil, Charles F (advisor), Raitt, Lincoln (advisor), Zedda, Luciana (advisor).

Subjects/Keywords: Climate warming; Diurnal measurements; Effective temperature; Elemental concentrations; Fog and dew precipitation; Lethal temperature; Lichens; Moisture uptake; Photosynthetic quantum yield; Respiration

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APA (6th Edition):

Maphangwa, K. W. (2010). Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem . (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/2545

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):

Maphangwa, Khumbudzo Walter. “Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem .” 2010. Thesis, University of the Western Cape. Accessed January 23, 2020. http://hdl.handle.net/11394/2545.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Maphangwa, Khumbudzo Walter. “Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem .” 2010. Web. 23 Jan 2020.

Vancouver:

Maphangwa KW. Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem . [Internet] [Thesis]. University of the Western Cape; 2010. [cited 2020 Jan 23]. Available from: http://hdl.handle.net/11394/2545.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Maphangwa KW. Lichen thermal sensitivities, moisture interception and elemental accumulation in an arid South African ecosystem . [Thesis]. University of the Western Cape; 2010. Available from: http://hdl.handle.net/11394/2545

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of the Western Cape

2. Matimati, Ignatious. The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem .

Degree: 2009, University of the Western Cape

Fog and dew interception and utilization by plant canopies remains one of the least considered aspects of vegetation studies at any scale yet the few studies that have been conducted point to their considerable influence on ecological processes and a critical role in modulating climate in southern African arid ecosystems. Their relevance to succulent plant hydrology was investigated in this study.The first study measured stable 18O and 2H isotope ratios in samples of rain, fog and dew water and compared these with those assayed monthly in stem xylem water of six succulent shrub species over a one year period. Negative 18O and 2H ratios were observed in the stem xylem water of all six species signifying a predominance of water derived from fog and dew precipitation which was most conspicuous during the wet winter. This implied that fog and dew are even more important sources of water than rain and corroborated by significant correspondence found between fog and dew frequencies, succulent foliar water contents and quantum yields of photochemistry.The second study monitored variations in stem diameter at 2-hourly intervals in 8 succulent shrub species of diverse growth form over a 9-month period. Two groups of species were distinguished based on whether their daily amplitudes in stem diameter were consistently positively correlated with daily fluxes in vapour pressure deficit, which were indicative of a persistent CAM photosynthetic mode, or intermittently correlated with daily fluxes in vapour pressure deficit, which were indicative of mixed CAM and C3 photosynthetic modes. Among species displaying a persistent CAM photosynthetic mode, high nocturnal fog and dew precipitation amounts corresponded with low daily amplitudes in stem diameter, and vice versa, which pointed to reduced nocturnal stomatal water loss. These patterns, which were indistinct among species displaying mixed CAM and C3 photosynthetic modes, were corroborated by small daily amplitudes in stem diameter also consistently observed in one species displaying a CAM photosynthetic mode in ambient than artificially fog and dew excluded environments.The third study monitored changes in water mass at hourly intervals of quartz gravel substrates with different dwarf succulent species assemblages over an 8-month period.Consistently greater net amounts of water were intercepted daily by quartz gravel substrates containing Agyroderma pearsonii than Cephalophylum spissum plants as well as those without plants. These attributed to a high water repellence of A. pearsonii leaves and less radiation absorbed by the paler silvery to grey-green leaves of A. pearsonii leaves than the dark green leaves of C. spissum resulting in lower leaf temperatures and less water loss by transpiration. Quartz gravel soils devoid of plants intercepted nearly 5-times greater amounts of precipitation contributed by fog and dew than that contributed by rain. These precipitation amounts exceeding the high percentages of total hydrological input contributed by fog and dew reported… Advisors/Committee Members: Musil, Charles F (advisor), Raitt, Lincoln (advisor), February, Edmund (advisor).

Subjects/Keywords: CAM and C3 photosynthetic mode; Fog and dew precipitation; Foliar nitrogen; Foliar phosphorous; Malate accumulation; PSII function; Stem diameter variation sensor; Succulent karoo; Succulent plants; Vapour pressure deficit

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Matimati, I. (2009). The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem . (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/3354

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):

Matimati, Ignatious. “The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem .” 2009. Thesis, University of the Western Cape. Accessed January 23, 2020. http://hdl.handle.net/11394/3354.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Matimati, Ignatious. “The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem .” 2009. Web. 23 Jan 2020.

Vancouver:

Matimati I. The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem . [Internet] [Thesis]. University of the Western Cape; 2009. [cited 2020 Jan 23]. Available from: http://hdl.handle.net/11394/3354.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Matimati I. The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystem . [Thesis]. University of the Western Cape; 2009. Available from: http://hdl.handle.net/11394/3354

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Helsinki

3. Sotunde, Sobowale Adedapo. Improving water shortages through DF trap : Case study Nigeria.

Degree: Department of Agricultural Sciences; Helsingfors universitet, Agrikultur- och forstvetenskapliga fakulteten, Institutionen för lantsbruksvetenskaper, 2016, University of Helsinki

In meeting the crop water needs in the arid and semi-arid regions, alternative source of water must be explored, like the harvesting of dew and fog. To estimate the quantity of potential harvestable water in semi-arid Nigeria, a 3-hourly meteorological data from 8 weathers stations across the semi-arid region of Nigeria were analysed. The data; from January to December 2009; was retrieved in June 2015 from the European Center for Medium range Weather Forecasting (ECMWF) database, by the Finnish Meteorological Institute (FMI). The available data includes the wind speed (WS) and direction, air temperature, and the relative humidity (RH). From the available data, the following needed parameters to calculate the potential water harvestable in each area were first calculated; the air saturated vapour pressure, air vapour pressure, absolute humidity, and finally the potential water harvestable through air humidity over 3hours (WH3). Only the RH ≥69% were used in calculating the WH3, at lower values water harvesting isn’t possible. Also, only the WS ≤2 was used, at higher values of WS, evaporation occurs. All the areas showed the possibility of harvesting water from dew and fog. The possibility was however higher during the wet season both in quantity and in frequency in all the areas considered than in the dry season.

Subjects/Keywords: dew; fog; water harvesting; relative humidity; semi arid; arid; Agroteknologi; Agrotechnology; Agroteknologia

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Sotunde, S. A. (2016). Improving water shortages through DF trap : Case study Nigeria. (Masters Thesis). University of Helsinki. Retrieved from http://hdl.handle.net/10138/161667

Chicago Manual of Style (16th Edition):

Sotunde, Sobowale Adedapo. “Improving water shortages through DF trap : Case study Nigeria.” 2016. Masters Thesis, University of Helsinki. Accessed January 23, 2020. http://hdl.handle.net/10138/161667.

MLA Handbook (7th Edition):

Sotunde, Sobowale Adedapo. “Improving water shortages through DF trap : Case study Nigeria.” 2016. Web. 23 Jan 2020.

Vancouver:

Sotunde SA. Improving water shortages through DF trap : Case study Nigeria. [Internet] [Masters thesis]. University of Helsinki; 2016. [cited 2020 Jan 23]. Available from: http://hdl.handle.net/10138/161667.

Council of Science Editors:

Sotunde SA. Improving water shortages through DF trap : Case study Nigeria. [Masters Thesis]. University of Helsinki; 2016. Available from: http://hdl.handle.net/10138/161667

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