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You searched for +publisher:"University of Manitoba" +contributor:("Kenkel, Norm"). Showing records 1 – 3 of 3 total matches.

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University of Manitoba

1. Kowal, Paige. A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent.

Degree: Biological Sciences, 2019, University of Manitoba

Netley-Libau Marsh in Manitoba, Canada is a 26 000 hectare coastal, freshwater marsh located at the mouth of the Red River on the south shore of Lake Winnipeg. Shoreline erosion and loss of emergent vegetation since 1929 has resulted in large expanses of open water and an overall degradation to the marsh ecosystem. Six coastal marshes of similar size and all connected to the south basin of Lake Winnipeg were selected for comparison to determine if marsh vegetation loss is widespread in Lake Winnipeg coastal marshes or limited to Netley-Libau Marsh. As a measure of degradation, open water area measurements of the study marshes were digitized from aerial and satellite images taken between the years of 1929 and 2015. Distinguishing the effects of Red River discharge into the west side of Netley-Libau Marsh from that of Lake Winnipeg regulation was confounded by the finding that direct river connection to the marsh was not firmly established until approximately 1970, just six years prior to the commencement of lake regulation. Red River discharges upstream of Netley-Libau Marsh did not significantly account for variation in open water areal extent within the two Netley-Libau Marsh study areas, nor did modelled Netley Cut discharges. Between 56-95% of the variation in open water areal extent within the six study marshes was explained by two growing seasons of average May-October Lake Winnipeg water levels. Variation in open water areal extent was not comparable in all six study marshes and the frequency and duration of low-water periods decreased after 1976. My findings show that the loss of habitat complexity and emergent vegetation in Lake Winnipeg coastal wetlands has been ongoing since the early 20th century and is attributed most heavily to the decrease in low-water periods in Lake Winnipeg levels. The greatest loss of open water area within Netley-Libau Marsh occurred in years when average Lake Winnipeg water surface elevation decreased to 217 metres above sea level during typical ice-free months (May-October). These findings highlight the importance of periodic lowering of Lake Winnipeg water levels in promoting coastal marsh vegetation growth and future habitat restoration efforts. Advisors/Committee Members: Goldsborough, Gordon (Biological Sciences) (supervisor), Kenkel, Norm (Biological Sciences) (examiningcommittee), Iacozza, John (Environment and Geography) (examiningcommittee).

Subjects/Keywords: Emergent; Macrophyte; Hydrology; GIS; Netley-Libau

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

APA (6th Edition):

Kowal, P. (2019). A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/33869

Chicago Manual of Style (16th Edition):

Kowal, Paige. “A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent.” 2019. Masters Thesis, University of Manitoba. Accessed October 23, 2019. http://hdl.handle.net/1993/33869.

MLA Handbook (7th Edition):

Kowal, Paige. “A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent.” 2019. Web. 23 Oct 2019.

Vancouver:

Kowal P. A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent. [Internet] [Masters thesis]. University of Manitoba; 2019. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/1993/33869.

Council of Science Editors:

Kowal P. A historical analysis of the changes in connectivity and plant cover in Netley-Libau Marsh, Manitoba, Canada: Distinguishing the effects of Lake Winnipeg and Red River hydrology on coastal marsh emergent macrophyte areal extent. [Masters Thesis]. University of Manitoba; 2019. Available from: http://hdl.handle.net/1993/33869


University of Manitoba

2. Pauline K. Catling. The classification of alvar vegetation in the Interlake region of Manitoba, Canada.

Degree: Biological Sciences, 2016, University of Manitoba

Alvars are globally rare rock barren ecosystems on limestone pavement. This thesis focused on the quantitative classification of vegetation of Manitoba alvars, the relationships between vegetation patterns and environmental factors and the effects of grazing on vegetation. Vegetation plots were completed across twenty sites. Cluster analysis, indicator species analysis and PCA were used to describe eight vegetation types. A RDA revealed moisture regime, soil depth, bare rock cover and disturbance (grazing and browsing) are the most important factors affecting floristic composition. Grazing effects were studied at two sites using paired plots on either side of a fenceline dividing grazed and ungrazed areas. PCA and RDA showed significant difference between vegetation compositions based on grazing. A partitioning of species richness and diversity by introduced and native species revealed that both sites experienced significant replacement by introduced species. Current grazing levels on Manitoba alvars are severely impacting the vegetation of this ecosystem. Advisors/Committee Members: Kenkel, Norm (Biological Sciences), Worley, Anne (Biological Sciences).

Subjects/Keywords: alvar; limestone pavement; plant ecology; vegetation classification; disturbance; vegetation dynamics; species associations

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

APA (6th Edition):

Catling, P. K. (2016). The classification of alvar vegetation in the Interlake region of Manitoba, Canada. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/31818

Chicago Manual of Style (16th Edition):

Catling, Pauline K.. “The classification of alvar vegetation in the Interlake region of Manitoba, Canada.” 2016. Masters Thesis, University of Manitoba. Accessed October 23, 2019. http://hdl.handle.net/1993/31818.

MLA Handbook (7th Edition):

Catling, Pauline K.. “The classification of alvar vegetation in the Interlake region of Manitoba, Canada.” 2016. Web. 23 Oct 2019.

Vancouver:

Catling PK. The classification of alvar vegetation in the Interlake region of Manitoba, Canada. [Internet] [Masters thesis]. University of Manitoba; 2016. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/1993/31818.

Council of Science Editors:

Catling PK. The classification of alvar vegetation in the Interlake region of Manitoba, Canada. [Masters Thesis]. University of Manitoba; 2016. Available from: http://hdl.handle.net/1993/31818

3. Lastra, Rod. Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada.

Degree: Biological Sciences, 2011, University of Manitoba

The encroachment of woody species into grassland and savanna ecosystems has been well document since the early 1800s. Within the parkland ecoregion of western Canada, trembling aspen (Populus tremuloides Michx.) has been one of the key tree species increasing in dominance. Aspen encroachment is best explained not by single mechanism, but rather by a number of interacting ecological factors. In this study I examined the ecological consequences of the clonal biology in aspen as a means to explain persistence and observed tree-grass ratios within grassland savannas of western Canada. Results suggest that aspen stands cycle between a “stable” phase characterized by a dense mature canopy, and an “unstable” phase characterized by canopy breakup and increased regeneration from root suckers. It is during this unstable phase that clonal encroachment is likely to occur. Within these mature stands, different-aged ramets promote persistence by maximizing developmental variation. Such a mechanism overcomes the functional phenotypic uniformity of ramets within a single age-structured stand. Results from my study indicate that physiological integration is beneficial to the growth and survivorship of regenerating and encroaching aspen ramets. My results also suggest that the benefits of physiological integration are greatest in more stressful environments, and in recently established post-fire ramets. Finally, the consequences of variation in adaptive ecological relevant traits among individuals was examined by determining differences in vigor among aspen clones in relation to the production of secondary compounds (phenolic glycosides). My results demonstrate a high degree of variation in leaf phenolic glycosides production among clones. A significant amount of this variation was accounted for by differences in clone vigor (within population: individual susceptibility hypothesis), with a smaller amount related to environmental differences (among populations). In all instances, vigorous clones were significantly higher in levels of phenolic glycosides compared with dieback clones, suggesting that some individuals may be predisposed to undergo density-independent mortality. This has important ecological implications, because it implies that one of the key mechanisms regulating population dynamics, community interactions and biodiversity may be related to intrinsic adaptive differences in susceptibility among individuals. Advisors/Committee Members: Kenkel, Norm (Biological Sciences) (supervisor), Ford, Bruce (Biological Sciences) Lobb, David (Soil Science) Wilmshurst, John (Biological Sciences) Lieffers, Vic (University of Alberta, Department of Renewable Resources) (examiningcommittee).

Subjects/Keywords: woody encroachment; trembling aspen; aspen parkland; browsing; intraspecific variation; clone vigor

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

APA (6th Edition):

Lastra, R. (2011). Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada. (Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/4828

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):

Lastra, Rod. “Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada.” 2011. Thesis, University of Manitoba. Accessed October 23, 2019. http://hdl.handle.net/1993/4828.

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

MLA Handbook (7th Edition):

Lastra, Rod. “Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada.” 2011. Web. 23 Oct 2019.

Vancouver:

Lastra R. Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada. [Internet] [Thesis]. University of Manitoba; 2011. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/1993/4828.

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

Council of Science Editors:

Lastra R. Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada. [Thesis]. University of Manitoba; 2011. Available from: http://hdl.handle.net/1993/4828

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

.