Spelling suggestions: "subject:"ecoregion"" "subject:"mesoregion""
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A phytosociological synthesis of Mopanieveld vegetation at different spatial scales using various classification methods / Frances SiebertSiebert, Frances January 2012 (has links)
Classification of relevé data aims to present the best possible explanation of the vegetation
within a specific study area. The variety of multivariate techniques available to classify
vegetation into ecological communities has developed in recent years, which contributes to
uncertainty among vegetation scientists as to which methods and computer software to select
for optimum classification results. The wide application of the classical TWINSPAN algorithm
along with the Braun-Blanquet approach of plant community descriptions and diagnostic
species identification in southern Africa prompted a comparison of classification results
between these classical approaches and a modern approach. The modern approach, as
being referred to in this study, entails the recent improvement on the classical TWINSPAN
algorithm, namely the Modified TWINSPAN algorithm in combination with statistical measures
of species fidelity. Comparisons between classification end-results were undertaken at
various spatial scales to test whether discrepancies between results obtained from the
different approaches are similar when applied to a broad-scale synthesis, an intermediate
synthesis and a local-scale classification within a similar vegetation type, the Mopaneveld.
Such a comparative study is envisaged to present insight on the credibility of the use of
classical approaches in phytosociology at various spatial scales.
A modern approach was tested upon three previous vegetation classification studies which
followed the classical approach. These vegetation classification studies were all undertaken
at different spatial scales and are being referred to as the reference classifications. The data
that were subjected to the modern approach were analogous to those used in the reference
classifications. The computer package JUICE 7.0 was used in which the Modified
TWINSPAN algorithm was applied in combination with statistical measures of species
fidelity, which was obtained as a function directly in the JUICE program. Classification
hierarchies were constructed for both the classical and modern approach results to compare
and describe similarities and discrepancies between the different hierarchical dendrograms.
Fidelity syntables were constructed to assist in the grouping of diagnostic species according
to highest fidelity values. Such diagnostic species groups were compared with the lists of
diagnostic species in the reference classifications.
At the broadest spatial scale, comparisons revealed discrepancies between classification
results from the classical and the modern approach. The modern approach presented a
more robust synthesis of the Mopaneveld in southern Africa since the vegetation units and
their associated diagnostic species are ecologically better expressed. The intermediate scale synthesis comparison revealed similar discrepancies, which again question the
credibility of the classical approach at broader spatial scales. The application of the modern
approach to the local scale classification, however, revealed little difference with the results
obtained through the classical approach. Although more alternative classification techniques
need to be applied to report on the most robust technique for vegetation classifications
across spatial scales, it could be reported that the classical TWINSPAN algorithm is not
favorable for vegetation classifications and syntheses beyond the local scale.
The ecological reliability of the modern approach at the intermediate scale prompted its
application in a synthesis of the riparian vegetation within the Mopane Bioregion of South
Africa, which was not achieved in any previous study. Riparian vegetation plays an important
role in maintaining good water quality and also provides habitat for many species. Riparian
vegetation therefore needs to be classified and described. The synthesis of the riparian
vegetation in the Mopane Bioregion of South Africa revealed six distinct plant communities
which are described and discussed in terms of diagnostic, constant and dominant species
along with variance in plant species diversity. / Thesis (Ph.D. (Botany))--North-West University, Potchefstroom Campus, 2012
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A phytosociological synthesis of Mopanieveld vegetation at different spatial scales using various classification methods / Frances SiebertSiebert, Frances January 2012 (has links)
Classification of relevé data aims to present the best possible explanation of the vegetation
within a specific study area. The variety of multivariate techniques available to classify
vegetation into ecological communities has developed in recent years, which contributes to
uncertainty among vegetation scientists as to which methods and computer software to select
for optimum classification results. The wide application of the classical TWINSPAN algorithm
along with the Braun-Blanquet approach of plant community descriptions and diagnostic
species identification in southern Africa prompted a comparison of classification results
between these classical approaches and a modern approach. The modern approach, as
being referred to in this study, entails the recent improvement on the classical TWINSPAN
algorithm, namely the Modified TWINSPAN algorithm in combination with statistical measures
of species fidelity. Comparisons between classification end-results were undertaken at
various spatial scales to test whether discrepancies between results obtained from the
different approaches are similar when applied to a broad-scale synthesis, an intermediate
synthesis and a local-scale classification within a similar vegetation type, the Mopaneveld.
Such a comparative study is envisaged to present insight on the credibility of the use of
classical approaches in phytosociology at various spatial scales.
A modern approach was tested upon three previous vegetation classification studies which
followed the classical approach. These vegetation classification studies were all undertaken
at different spatial scales and are being referred to as the reference classifications. The data
that were subjected to the modern approach were analogous to those used in the reference
classifications. The computer package JUICE 7.0 was used in which the Modified
TWINSPAN algorithm was applied in combination with statistical measures of species
fidelity, which was obtained as a function directly in the JUICE program. Classification
hierarchies were constructed for both the classical and modern approach results to compare
and describe similarities and discrepancies between the different hierarchical dendrograms.
Fidelity syntables were constructed to assist in the grouping of diagnostic species according
to highest fidelity values. Such diagnostic species groups were compared with the lists of
diagnostic species in the reference classifications.
At the broadest spatial scale, comparisons revealed discrepancies between classification
results from the classical and the modern approach. The modern approach presented a
more robust synthesis of the Mopaneveld in southern Africa since the vegetation units and
their associated diagnostic species are ecologically better expressed. The intermediate scale synthesis comparison revealed similar discrepancies, which again question the
credibility of the classical approach at broader spatial scales. The application of the modern
approach to the local scale classification, however, revealed little difference with the results
obtained through the classical approach. Although more alternative classification techniques
need to be applied to report on the most robust technique for vegetation classifications
across spatial scales, it could be reported that the classical TWINSPAN algorithm is not
favorable for vegetation classifications and syntheses beyond the local scale.
The ecological reliability of the modern approach at the intermediate scale prompted its
application in a synthesis of the riparian vegetation within the Mopane Bioregion of South
Africa, which was not achieved in any previous study. Riparian vegetation plays an important
role in maintaining good water quality and also provides habitat for many species. Riparian
vegetation therefore needs to be classified and described. The synthesis of the riparian
vegetation in the Mopane Bioregion of South Africa revealed six distinct plant communities
which are described and discussed in terms of diagnostic, constant and dominant species
along with variance in plant species diversity. / Thesis (Ph.D. (Botany))--North-West University, Potchefstroom Campus, 2012
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A Holistic Approach to Animal Farming: Integrating Bioregionalism and Socialist Ecofeminism Within the Context of Concentrated Animal Feeding OperationsSpears, Sarah R 01 January 2024 (has links) (PDF)
This paper addresses the harmful effects of concentrated animal feeding operations (CAFOs) within animal farming systems, including poor animal welfare, environmental damage, and environmental injustice. I argue that bioregionalism and socialist ecofeminism can help inform a holistic approach to mitigating these harms and evoke ethical and sustainable animal farming systems. Bioregionalism emphasizes local resource use, community engagement, and ecological knowledge within a specific region, while socialist ecofeminism critiques oppressive systems and seeks to uplift the viewpoints of all beings, including animals, nature, and humans of various identities. Through a scaffolded hypothetical case study informed by the CAFOs-practicing hog farms in the coastal plain of North Carolina, I examine the potential benefits and limitations of a solely bioregional animal farming system followed by the potential benefits and limitations of a solely socialist ecofeminist animal farming system. I then combine the two theories to explore how they complement one another. I conclude that an ecologically informed structure advocated by bioregionalism functioning together with the moral values of socialist ecofeminism creates the possibility for ethical and sustainable animal farming systems.
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Ecological connectivity, adult animal movement, and climate change: implications for marine protected area design when data are limitedFriesen, Sarah K 15 July 2019 (has links)
Marine protected areas (MPAs) are important conservation tools that can support the resilience of marine ecosystems. Many countries, including Canada, have committed to protecting at least 10% of their marine areas under the Convention on Biological Diversity’s Aichi Target 11, which includes connectivity as a key aspect. Connectivity, the movement of individuals among habitats, can enhance population stability and resilience within and among MPAs. This thesis aimed to understand regional spatial patterns of marine ecological connectivity, specifically through the mechanism of adult movement, and how these patterns may be affected by climate change. I used the Northern Shelf Bioregion in British Columbia, Canada, as a case study for four objectives: (1) evaluate potential connectivity via adult movement for the entire bioregion, using habitat proxies for distinct ecological communities; (2) assess potential connectivity via adult movement among existing and potential MPAs, using the same habitat proxies; (3) model potential connectivity via adult movement among marine protected areas for two focal species (Metacarcinus magister and Sebastolobus alascanus) and predict how this interconnectedness may shift based on projected ocean temperature changes; and (4) contribute the results of these analyses to the MPA technical team’s ongoing planning process so that connectivity may be considered in the implementation of a new MPA network in the bioregion. This thesis developed an approach to assess and design MPA networks that maximize inferred connectivity within habitat types for adult movement when ecological data are limited. It applied least-cost theory and circuit theory to model MPA suitability and interconnectedness, finding that these are projected to decrease for Sebastolobus alascanus but increase for Metacarcinus magister. I showcased some methods that may be used in MPA design and evaluation, with lessons for other contexts. Importantly, this thesis informed an ongoing MPA planning process, enabling ecological connectivity to be considered in the establishment of a new MPA network in the bioregion. Overall, this work provided examples for incorporating connectivity and climate change into MPA design, highlighting what is possible even when data are limited. / Graduate
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Life in the Land: The Story of the Kaibab DeerPrendergast, Neil Douglas 16 August 2005 (has links)
No description available.
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Life in the land the story of the Kaibab deer /Prendergast, Neil Douglas. January 2005 (has links)
Thesis (M.A.)--Miami University, Dept. of History, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], ii, 89 p. : maps. Includes bibliographical references (p. 70-89).
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