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Ecosystem engineering impacts of invasive species on river banks : signal crayfish and Himalayan balsamFaller, Matej January 2018 (has links)
This thesis investigates the impact of two invasive ecosystem engineers on the river banks. Invasive species generate significant global environmental and economic costs and represent a particularly potent threat to freshwater ecosystems. Ecosystem engineers are organisms that modify their physical habitat. Therefore this thesis will explore the interaction of these two types of species and their impacts on the example of the impact of signal crayfish and Himalayan balsam The obtained results indicate that there are few avenues through which invasive ecosystem engineers can influence river bank processes. While many uncertainties remain, due to the intrinsic complexity of river ecosystems, a multitude of anthropogenic stressors that they are increasingly subjected to and a wide array of ecosystem services that rivers provide to people, it is important to consider the role of invasive ecosystem engineers in river management practices. on river banks. The work included analyses and development of conceptual models for the understanding of invasive ecosystem engineers, followed by four research chapters aimed at answering specific questions. A study of signal crayfish impact is primarily focused on the impact of burrows that crayfish dig as shelter and their influence on riverbank erosion. The interaction between habitat characteristics, the occurrence of burrows and erosion is analysed on three different levels of spatial scale: bank section in reach, reach in the catchment and bank section in the catchment. Bank section in reach survey (Chapter 4) focused on a reach heavily impacted by crayfish burrowing on the River Windrush, UK, in order to study the maximum effect of burrowing. Also, smaller spatial extent enabled detailed study of three sets of variables as well as an assessment of the impact that signal crayfish population density has on burrowing. Reach in catchment spatial scale expanded the survey to cover 103 river reaches in the Thames catchment and was based on a combination of habitat information from publicly available online data sets, primarily the River Habitat Survey database and rapid field surveys that recorded burrows and erosion. Bank section in catchment-scale was based on the same 103 sites, but the main focus of field observations were ten metres long bank sections for which habitat, burrows and erosion information were collected. Overall, burrowed banks were more likely to be characterised by cohesive bank material, steeper bank profiles with large areas of bare bank face, often on outer bend locations and were associated with bank profiles with signs of erosion. There were indications that signal crayfish burrowing is contributing to the river bank erosion, but no conclusive results have been made. Study of the impact of the Himalayan balsam was undertaken on eight sites at the River Brenta in Italy and it was focused on three main aspects. Firstly it was established that extent of Himalayan balsam domination over native vegetation varies widely depending on the habitat conditions and native plants encountered. Secondly, it was established that there are no conclusive differences in the extent of erosion and deposition on transects covered by native vegetation and Himalayan balsam. Thirdly, measurement of traits of individual plants showed significant differences in traits of individual plants that are known to have consequences for river bank erosion and deposition.
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Sustaining ecosystem functions under environmental change : the combined impacts of temperature, species diversity and limiting resources on phytoplankton communitiesLewington-Pearce, Leah January 2018 (has links)
Plankton play a key role in regulating nutrient and carbon cycles in freshwater ecosystems. The uptake and processing of nutrients in planktonic biomass are highly sensitive to changes in the environment, such as alterations in the availability of limiting nutrients, increasing temperature due to climate change, and changes to the composition of interacting species. The focus of this thesis is to use a variety of experimental and theoretical methods to assess and predict the impact of multiple perturbations on community structure, dynamics and ecosystem function, with a particular focus on interactions between phytoplankton and their consumers (zooplankton). Increases in both temperature and phytoplankton species diversity independently decreased CO2 concentrations when the number of non-resource species (those inedible to the zooplankton) were high. Using structural equation modeling I show that the effect is indirect, resulting largely from the positive impacts on total biomass of phytoplankton. Phytoplankton are limited by a range of resources, and differences in the functional traits used to utilize light and nutrients can explain the distributions of species under different temperature regimes. I found that under light and nitrogen limitation, resource requirements are generally lowest at intermediate temperatures, and that changes in temperature may therefore alter the competitive hierarchy amongst species. Using the model freshwater phytoplankton Chlamydomonas reinhardtii, I also find that previous selection environments govern future competitive abilities in phytoplankton. Adaptation to a high salt and low nutrient stress increases competitive ability under light limited conditions, indicating a strong dependency of selection environment for overall competitiveness. This thesis provides a mechanistic insight into the role of diverse plankton communities for community dynamics and ecosystem functioning.
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Evaluating Methods to Describe Dietary Patterns of Lake Michigan SalmonidsBenjamin S. Leonhardt (5930720) 18 December 2018 (has links)
<div>Documenting trophic relationships in aquatic ecosystems can facilitate understanding of not only system processes, but also the potential responses of food webs to stressors. Often, trophic studies assume consistent behavior and trophic roles among individuals in a population, but intraspecific diet variation, such as individual specialization, can play a critical role in food web complexity and can promote ecosystem resilience. In Lake Michigan, the introduction of invasive species (e.g., zebra mussel, Dreissena polymorpha; quagga mussel, Dreissena bugensis; round goby, Neogobius melanostomus) and reduced nutrient loading has resulted in changes in nutrient dynamics, system productivity, and community composition over the past two decades. As a result, abundances of many forage fish have declined, including alewife (Alosa pseudoharengus) which have historically supported the five dominant salmonid species of Lake Michigan (brown trout, Salmo trutta; Chinook salmon, Oncorhynchus tshawytscha; Coho salmon, Oncorhynchus kisutch; lake trout, Salvelinus namaycush; rainbow trout, Oncorhynchus mykiss). With these ecosystem changes, there is uncertainty as to the extent of how different species of salmonids will transition to alternative prey items (e.g., round goby). Common methods for examining diet patterns and trophic linkages include stomach content analysis, stable isotope ratios (e.g., δ13C and δ15N), and fatty acid composition, but these methods vary in temporal resolution and have differential biases. Furthermore, elucidating agreement of these trophic indicators and whether or not agreement is consistent across species can improve their use in future food web studies. The first research chapter of this thesis investigated the diet complexity of Lake Michigan salmonids by evaluating stomach content composition, diversity, and potential specialized consumption of different alewife lengths. Stomach contents revealed that Chinook salmon almost exclusively consumed alewife and had a lower diet diversity compared to the other four species, which consumed round goby (brown trout and lake trout), aquatic invertebrates (Coho salmon), and terrestrial invertebrates (rainbow trout) in addition to alewife. Although there were clear spatio-temporal and size-related feeding patterns for each species, much of the variation in diet composition and diet diversity was present at the individual-level. Additionally, salmonid species appeared to consume the entire size range of alewife that were available to them and individually specialized on alewife lengths. Due to their reliance on alewife, it is likely that Chinook salmon may be more negatively impacted than other salmonid species if alewife abundance continue to decline in Lake Michigan. The second research chapter assessed the agreement of multiple trophic indicators. Although we found agreement among trophic indicators across the five salmonid species using linear and logistic models, particularly between stomach contents, δ13C, and fatty acid 16:1n-7, there was significant variation in relationships across species, potentially due to variation among salmonids in specific prey items consumed (e.g., alewife and round goby) and species-specific regulation of fatty acids. Additionally, δ15N estimated from stomach contents using linear mixing models were typically greater relative to observed δ15N, which may suggest small alewife were underrepresented in stomachs of 2016 angler-caught salmonids. Lastly, stomach contents underestimated benthic resource use by rainbow trout, which may be related to biases associated with fish collection methods and stomach content analysis. Overall, the results of trophic indicator comparisons indicate that caution should be taken when generalizing trophic relationships across species and to consider biases associated with trophic indicators, especially when relying on a single diet metric.</div>
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Preservation of ecosystems of international watercourses and the integration of relevant rulesLee, Jing January 2012 (has links)
The unprecedented degradation of freshwater ecosystems due to the rampant exploitation of water resources re-establishes the importance of preserving freshwater ecosystems in order to ensure their continued viability that supports the attainment of sustainable development. This concern is addressed in Article 20 of the 1997 Watercourses Convention that specifically provides for the preservation of ecosystems of international watercourses. However, the interpretation and the subsequent application of this obligation are complicated by the proliferation of international instruments concerning the environment, which leads to the fragmentation of international law. In response to the apprehension raised over the undesirable consequences of the fragmentation of international law, the potential of Article 31(3)(c) of the 1969 Vienna Convention as an interpretative mechanism that enables the systemic integration of rules has come into the limelight. The objective of the present thesis, titled ‘Preservation of Ecosystems of International Watercourses and the Integration of Relevant Rules’ is to develop a interpretative framework for the operationalisation of Article 31(3)(c) that allows the full realisation of its potential as a tool of integration. A three-tier operationalisation framework that re-interprets the salient features of Article 31(3)(c) through the prism of an interactional understanding of international law is developed and executed through Chapters Two to Eight, where Chapter Nine provides a general conclusion of the thesis. The reconstruction of existing interpretation of Article 31(3)(c) provides a new understanding of this Article, which enables the realisation of its systemic integration potential. The application of this framework of operationalisation in the interpretation of the obligation to preserve ecosystems of international watercourses stipulated under Article 20 reflects contemporaneous development in international environmental law, and enhances the normative content and scope of Article 20.
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Savages versus settlers, wildness versus wheatfields : an ecocritical approach to the (European) settlement story in early Canadian Prairie fictionTernier Daniels, Elizabeth Frances 18 July 2008
The experience of wilderness and of homesteading on the prairies provided the primary subject matter for Canadian prairie fiction in the final decades of the nineteenth century and the first decades of the twentieth century. My thesis uses ecocriticism to make a connection between the cultural values embedded in this literature and the ecological consequences of European settlement. It uses the philosophical concepts of bioregionalism, deep ecology and ecofeminism as the ideological framework for a study of novels and short stories published prior to 1930. It uses the theoretical concepts of cultural materialism to analyze, from a socio-ecological perspective, the power relationships within this body of literature. More specifically, it looks at the way in which English-speaking writers privileged the values of civilization above wildness and the values of western European culture above the cultures of Metis and indigenous peoples. My thesis divides early prairie fiction into the categories of wilderness romance and homesteading romance. It looks at representative samples of these genres, and concludes by discussing two examples of early prairie realism. Throughout the entire thesis I view the fictional treatment of European settlement from the perspective of current ecological thinking and, in doing so, provide a critique of both past and present attitudes to the prairie environment.<p>
The introduction provides a philosophical and critical approach to my study of literature and of its historical context. It traces the anthropocentric values of "old world" immigrants to the dominant ideology that developed in post-Medieval Europe: the Western Judaeo-Christian worldview of dominion over Nature, the faith in science and technology, and the materialist ideals of capitalism and economic progress. It considers the role that prairie fiction played in creating the cultural values that led to the modification of the natural prairie landscape, and explores the potential of critical theory to provide oppositional interpretations of the European settlement story. It then discusses the philosophical and theoretical framework of the ecocriticism that I use in my study of the interface between immigrant settlers, aboriginal people and the land.<p>
Chapter One introduces the wilderness romance. It defines the terms which I use to describe immigrant, aboriginal and mixed-blood peoples. It points out that the transcendent nature of the romance makes it an ideal form for a body of literature that privileges civilization above wildness and culture above Nature. It shows how the quest structure of the wilderness romance endorses the values of Western civilization, and uses a legend from one of these romances in order to illustrate the way in which they empower the dominant culture. Chapter One concludes by showing how the English-language definitions of "wild" and "civilized" work to elevate the culture of "old world" immigrants above the traditions of a semi-nomadic wilderness people.<p>
Chapter Two looks at the ambivalence to wildness apparent in two examples of the wilderness romance: R. M. Ballantyne's The Young Fur Traders, or Snowflakes and Sunbeams: A Tale of the Far North (1856) and William F. Butler's Red Cloud: A Tale of the Great Prairie (1882). It discusses both authors' use of Edenic imagery in their descriptions of the great Northwest, their differing views of aboriginal people and their pragmatic conclusions to the heroes' wilderness quest. It examines the implications of the protagonists' return to a prosperous, mercantile civilization, and points out that Ballantyne and Butler failed to recognize the incompatibility of their simultaneous images of the West as pristine wilderness and future home of a flourishing industrial economy.<p>
Chapter Three looks at the civilizing impact of Victorian Christianity in two examples of missionary fiction: R. M. Ballantyne's The Prairie Chief: A Tale (1886) and Egerton Ryerson Young's Oowikapun or How the Gospel Reached the Nelson River Indians (1896). It suggests that both novels privilege civilization above wildness by equating Christianity with the order and domestic virtue of Victorian culture and by equating native spirituality with untamed Nature. Since Christianity was an unquestioned good in the Victorian hegemony, and native spirituality a threat to Christian dominance, the values of civilization basked in the reflected virtue of Anglo-Protestant ideology while wilderness and Nature were tarnished by their association with pagan superstition and evil. Chapter Three shows how the successful achievement of the heroes' wilderness quests involves bringing the light of Christian civilization to the darkness of the heathen wilderness.<p>
Chapter Four examines the process of cultural genocide in two fur trade novels. It looks at the way in which Agnes Laut uses the captivity narrative in Lords of the North (1900) to illustrate the savage behavior of the uncivilized Indian, and the way in which Hulbert Footner uses the adventure story in The Fur Bringers: A Story of the Canadian Northwest (1920) to portray native and mixed-blood people as either wicked and cunning or naive, childlike and dependent. It shows how the authors attempt to invalidate the traditional culture of a wilderness people by comparing its apparent weaknesses with the stronger, morally superior culture of their white protagonists. Both novels thus validate the obliteration of aboriginal traditions and their replacement by the values and institutions of Western civilization.<p>Chapter Five uses three novels to explore the way in which romance writers used stories of native "rebellion" to justify the suppression of political resistance. Joseph Collins, an ardent Canadian nationalist, wrote Louis Riel The Rebel Chief (1885) to inflame Eastern opinion against the Metis "rebels" who threatened to destroy his vision of a strong and united nation; this chapter looks at his use of historical misrepresentation, inflammatory language and tragic melodrama to discredit the "barbarian" forces that threatened imperial law and order. Ralph Connor's later account of an abortive 1885 Indian uprising, in Corporal Cameron (1912) and The Patrol of the Sun Dance Trail (1914), is more sympathetic towards native people but it, too, privileges white civilization by equating the interests of immigrant ' settlers with the public good. By further associating the Indian and Metis "rebels" with the disorder and chaos of wild Nature, Collins and Connor helped to invalidate native resistance and to ensure Anglo-Canadian victory over the degraded "savages."<p>
Chapter Six looks at the connection between patriarchal power and the "old world" social order in Harwood Steele's Mounted Police romance, Spirit-of-Iron (1923). It shows how Steele privileges civilization above wildness by glorifying a para-military hierarchy based upon "masculine" strength and adherence to the values of Empire. Power accrues in Steele's novel to men whose fists and nerve and endurance enable them to enforce their will on women and Nature and weaker men. Chapter Six looks at the way in which this power hierarchy helped to convert an unproductive wilderness into a prosperous British colony, and reveals the enormous costs that women unwittingly pay for the privilege of supporting key (masculine) players in the drive towards "progress."<p>
Chapter Seven explores the connection between patriarchal man's dominance of woman and Nature in Douglas Durkin's The Heart of Cherry McBain (1919) and The Lob stick Trail (1921). It illustrates the symbiotic relationship between male dominance and economic progress in the building of two important patriarchal institutions--the railway and the mining industry. Durkin's novels cast a romantic glow over the men who risked life and capital to build roadbeds and to develop the mineral resources of the Northwest; Chapter Seven, however, shows how the rules which govern this development empower men at the expense of women and Nature, and reveals the high human and ecological costs of denying integrity to both the feminine and the natural world.<p>
Chapter Eight introduces the homesteading romance. It notes the conflicting impulses behind popular images of the West as pastoral utopia: the settler wants to create both an arcadian garden in the wilderness and a prosperous outpost of a mercantile civilization. It discusses the philosophical origins of the industrial market economy, and looks at the social, economic and ecological costs of commercial, export-oriented agriculture on the Canadian prairies. Chapter Eight notes the absence of indigenous and mixed-blood people in the homesteading romance, and discusses the unrealized potential of traditional Metis culture to provide immigrants with an ecologically appropriate response to the "new world". It discusses one French-Canadian novel, Georges Bugnet's Nipsya (1924; trans. 1929), which provides the only significant study of Metis culture in early prairie fiction.<p>
Chapter Nine looks at two novels which served as homesteading manuals for would-be immigrants. Both Alexander Begg's "Dot It Down;" A Story of Life in the North-West (1871) and W. H. P. Jarvis's The Letters of a Remittance Man to His Mother (1908) provide advice on farming for profit. Chapter Nine looks at the development of export agriculture on the prairies, and considers the role that Begg's and Jarvis's novels played in promoting high production and prosperity as the goals of farming. It points out that neither novel considers the economic climate created by a national policy which privileged business interests above the interests of farming, and concludes that they are therefore not only flawed guides to the development of sustainable agriculture but also unrealistic proponents of a materialist utopia.<p>
Chapter Ten looks at the contribution of two English novelists to the anthropocentric ideal of mastering wild Nature. Harold Bindloss's and Mrs. Humphrey Ward's prairie fiction portray strong, virile man who carve farms from the wilderness and transform "wasteland" into wheatfields. Guided by a dream of dominion over the natural world, they are rewarded both by wealth and by marriage to well-born English maidens. Bindloss and Ward celebrate the heroism of the stalwart men whose agricultural victories provide prosperity for the Canadian North West and bread for the people of England; Chapter Ten, however, traces the cultural roots of current environmental problems to anthropocentric values such as those embedded in their novels.<p>
Chapter Eleven examines the part that literature played in integrating "foreign" immigrants into an essentially British society. It looks at the process of assimilation in four prairie novels: Ralph Connor's The Foreigner: A Tale of Saskatchewan (1909), Flos Jewell Williams's New Furrows: A Story of the Alberta Foothills (1926), Eric Gill's Love in Manitoba (1911) and Laura Goodman Salverson's The Viking Heart (1923). These novels equate becoming a good Canadian with adoption of the mercantile ideals of economic progress and with rejection of the peasant ideals of self-sufficiency. As Chapter Eleven points out, they helped to obliterate the values of an "old world" peasantry which viewed land as sacred and simultaneously strengthened the Western imperative of human dominion over Nature.<p>
Chapter Twelve discusses the industrialization of agriculture in Robert Stead's Grain (1926). It points out that although Stead was critical of the greed and materialism that accompanied Western settlement, his novels reflect the anthropocentrism endemic to early prairie fiction. It looks at Stead's treatment of the homesteader's "sacred" mission to subdue the earth. It examines the historical context in which Grain is situated, and it discusses Stead's ambivalent--although ultimately favourable--response to the phenomenon of farm mechanization.<p>
Chapter Thirteen contrasts Western man's quest for wealth and power with woman's oppositional quest for healing community. Using Martha Ostenso's Wild Geese (1925), Arthur Stringer's Prairie trilogy (1915-22) and representative fiction of Nellie McClung (1908-25) as texts, it explores the way in which these writers privilege nurturing relationships above the exploitative relationships that characterize prairie agriculture. Stringer's heroine condemns her husband's obsession with money and power, and proposes an alternative ideology based upon love of family and home. Ostenso's Judith Gare rebels against patriarchal tyranny. McClung's protagonists serve as compassionate caregivers who view the land as a resource that provides sustenance--not wealth--for its human inhabitants. In their common opposition to an androcentric culture based on power over women and the land, these novels portray the feminine quest for healing community and for harmony between humans and their prairie home.<p>
Chapter Fourteen looks at two examples of early prairie realism--Frederick Philip Grove's Settlers of the Marsh (1925) and Our Daily Bread (1928). It discusses Grove's love for the prairie landscape, his admiration for the self-sufficient man of the soil, his distaste for economic ambition and his tragic view of life. It contrasts the tragic realism of Our Daily Bread with the comic spirit of reconciliation in Settlers of the Marsh, and suggests that the latter proves better adapted than tragedy as a form in which to cast the heroes' quest for nurturing community. <p>The Conclusion examines the role of the critic as social prophet and revisionary historian. It discusses the role of myth in influencing the course of history, summarizes the cultural impact of the myth of progress created by the wilderness and homesteading romance, notes the existence--and importance--of an oppositional quest for a harmonious relationship with the land, and reviews the role of bioregionalism, deep ecology and ecofeminism in providing the philosophical basis for a sustainable culture appropriate to the prairie bioregion. It considers the responsibility of both homesteaders and turn-of-the-century business entrepreneurs for current environmental degradation, and concludes that the dominant interests of urban politicians, consumers and business people have always been the impetus to agricultural expansion and the continuing depletion of prairie soils.
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Savages versus settlers, wildness versus wheatfields : an ecocritical approach to the (European) settlement story in early Canadian Prairie fictionTernier Daniels, Elizabeth Frances 18 July 2008 (has links)
The experience of wilderness and of homesteading on the prairies provided the primary subject matter for Canadian prairie fiction in the final decades of the nineteenth century and the first decades of the twentieth century. My thesis uses ecocriticism to make a connection between the cultural values embedded in this literature and the ecological consequences of European settlement. It uses the philosophical concepts of bioregionalism, deep ecology and ecofeminism as the ideological framework for a study of novels and short stories published prior to 1930. It uses the theoretical concepts of cultural materialism to analyze, from a socio-ecological perspective, the power relationships within this body of literature. More specifically, it looks at the way in which English-speaking writers privileged the values of civilization above wildness and the values of western European culture above the cultures of Metis and indigenous peoples. My thesis divides early prairie fiction into the categories of wilderness romance and homesteading romance. It looks at representative samples of these genres, and concludes by discussing two examples of early prairie realism. Throughout the entire thesis I view the fictional treatment of European settlement from the perspective of current ecological thinking and, in doing so, provide a critique of both past and present attitudes to the prairie environment.<p>
The introduction provides a philosophical and critical approach to my study of literature and of its historical context. It traces the anthropocentric values of "old world" immigrants to the dominant ideology that developed in post-Medieval Europe: the Western Judaeo-Christian worldview of dominion over Nature, the faith in science and technology, and the materialist ideals of capitalism and economic progress. It considers the role that prairie fiction played in creating the cultural values that led to the modification of the natural prairie landscape, and explores the potential of critical theory to provide oppositional interpretations of the European settlement story. It then discusses the philosophical and theoretical framework of the ecocriticism that I use in my study of the interface between immigrant settlers, aboriginal people and the land.<p>
Chapter One introduces the wilderness romance. It defines the terms which I use to describe immigrant, aboriginal and mixed-blood peoples. It points out that the transcendent nature of the romance makes it an ideal form for a body of literature that privileges civilization above wildness and culture above Nature. It shows how the quest structure of the wilderness romance endorses the values of Western civilization, and uses a legend from one of these romances in order to illustrate the way in which they empower the dominant culture. Chapter One concludes by showing how the English-language definitions of "wild" and "civilized" work to elevate the culture of "old world" immigrants above the traditions of a semi-nomadic wilderness people.<p>
Chapter Two looks at the ambivalence to wildness apparent in two examples of the wilderness romance: R. M. Ballantyne's The Young Fur Traders, or Snowflakes and Sunbeams: A Tale of the Far North (1856) and William F. Butler's Red Cloud: A Tale of the Great Prairie (1882). It discusses both authors' use of Edenic imagery in their descriptions of the great Northwest, their differing views of aboriginal people and their pragmatic conclusions to the heroes' wilderness quest. It examines the implications of the protagonists' return to a prosperous, mercantile civilization, and points out that Ballantyne and Butler failed to recognize the incompatibility of their simultaneous images of the West as pristine wilderness and future home of a flourishing industrial economy.<p>
Chapter Three looks at the civilizing impact of Victorian Christianity in two examples of missionary fiction: R. M. Ballantyne's The Prairie Chief: A Tale (1886) and Egerton Ryerson Young's Oowikapun or How the Gospel Reached the Nelson River Indians (1896). It suggests that both novels privilege civilization above wildness by equating Christianity with the order and domestic virtue of Victorian culture and by equating native spirituality with untamed Nature. Since Christianity was an unquestioned good in the Victorian hegemony, and native spirituality a threat to Christian dominance, the values of civilization basked in the reflected virtue of Anglo-Protestant ideology while wilderness and Nature were tarnished by their association with pagan superstition and evil. Chapter Three shows how the successful achievement of the heroes' wilderness quests involves bringing the light of Christian civilization to the darkness of the heathen wilderness.<p>
Chapter Four examines the process of cultural genocide in two fur trade novels. It looks at the way in which Agnes Laut uses the captivity narrative in Lords of the North (1900) to illustrate the savage behavior of the uncivilized Indian, and the way in which Hulbert Footner uses the adventure story in The Fur Bringers: A Story of the Canadian Northwest (1920) to portray native and mixed-blood people as either wicked and cunning or naive, childlike and dependent. It shows how the authors attempt to invalidate the traditional culture of a wilderness people by comparing its apparent weaknesses with the stronger, morally superior culture of their white protagonists. Both novels thus validate the obliteration of aboriginal traditions and their replacement by the values and institutions of Western civilization.<p>Chapter Five uses three novels to explore the way in which romance writers used stories of native "rebellion" to justify the suppression of political resistance. Joseph Collins, an ardent Canadian nationalist, wrote Louis Riel The Rebel Chief (1885) to inflame Eastern opinion against the Metis "rebels" who threatened to destroy his vision of a strong and united nation; this chapter looks at his use of historical misrepresentation, inflammatory language and tragic melodrama to discredit the "barbarian" forces that threatened imperial law and order. Ralph Connor's later account of an abortive 1885 Indian uprising, in Corporal Cameron (1912) and The Patrol of the Sun Dance Trail (1914), is more sympathetic towards native people but it, too, privileges white civilization by equating the interests of immigrant ' settlers with the public good. By further associating the Indian and Metis "rebels" with the disorder and chaos of wild Nature, Collins and Connor helped to invalidate native resistance and to ensure Anglo-Canadian victory over the degraded "savages."<p>
Chapter Six looks at the connection between patriarchal power and the "old world" social order in Harwood Steele's Mounted Police romance, Spirit-of-Iron (1923). It shows how Steele privileges civilization above wildness by glorifying a para-military hierarchy based upon "masculine" strength and adherence to the values of Empire. Power accrues in Steele's novel to men whose fists and nerve and endurance enable them to enforce their will on women and Nature and weaker men. Chapter Six looks at the way in which this power hierarchy helped to convert an unproductive wilderness into a prosperous British colony, and reveals the enormous costs that women unwittingly pay for the privilege of supporting key (masculine) players in the drive towards "progress."<p>
Chapter Seven explores the connection between patriarchal man's dominance of woman and Nature in Douglas Durkin's The Heart of Cherry McBain (1919) and The Lob stick Trail (1921). It illustrates the symbiotic relationship between male dominance and economic progress in the building of two important patriarchal institutions--the railway and the mining industry. Durkin's novels cast a romantic glow over the men who risked life and capital to build roadbeds and to develop the mineral resources of the Northwest; Chapter Seven, however, shows how the rules which govern this development empower men at the expense of women and Nature, and reveals the high human and ecological costs of denying integrity to both the feminine and the natural world.<p>
Chapter Eight introduces the homesteading romance. It notes the conflicting impulses behind popular images of the West as pastoral utopia: the settler wants to create both an arcadian garden in the wilderness and a prosperous outpost of a mercantile civilization. It discusses the philosophical origins of the industrial market economy, and looks at the social, economic and ecological costs of commercial, export-oriented agriculture on the Canadian prairies. Chapter Eight notes the absence of indigenous and mixed-blood people in the homesteading romance, and discusses the unrealized potential of traditional Metis culture to provide immigrants with an ecologically appropriate response to the "new world". It discusses one French-Canadian novel, Georges Bugnet's Nipsya (1924; trans. 1929), which provides the only significant study of Metis culture in early prairie fiction.<p>
Chapter Nine looks at two novels which served as homesteading manuals for would-be immigrants. Both Alexander Begg's "Dot It Down;" A Story of Life in the North-West (1871) and W. H. P. Jarvis's The Letters of a Remittance Man to His Mother (1908) provide advice on farming for profit. Chapter Nine looks at the development of export agriculture on the prairies, and considers the role that Begg's and Jarvis's novels played in promoting high production and prosperity as the goals of farming. It points out that neither novel considers the economic climate created by a national policy which privileged business interests above the interests of farming, and concludes that they are therefore not only flawed guides to the development of sustainable agriculture but also unrealistic proponents of a materialist utopia.<p>
Chapter Ten looks at the contribution of two English novelists to the anthropocentric ideal of mastering wild Nature. Harold Bindloss's and Mrs. Humphrey Ward's prairie fiction portray strong, virile man who carve farms from the wilderness and transform "wasteland" into wheatfields. Guided by a dream of dominion over the natural world, they are rewarded both by wealth and by marriage to well-born English maidens. Bindloss and Ward celebrate the heroism of the stalwart men whose agricultural victories provide prosperity for the Canadian North West and bread for the people of England; Chapter Ten, however, traces the cultural roots of current environmental problems to anthropocentric values such as those embedded in their novels.<p>
Chapter Eleven examines the part that literature played in integrating "foreign" immigrants into an essentially British society. It looks at the process of assimilation in four prairie novels: Ralph Connor's The Foreigner: A Tale of Saskatchewan (1909), Flos Jewell Williams's New Furrows: A Story of the Alberta Foothills (1926), Eric Gill's Love in Manitoba (1911) and Laura Goodman Salverson's The Viking Heart (1923). These novels equate becoming a good Canadian with adoption of the mercantile ideals of economic progress and with rejection of the peasant ideals of self-sufficiency. As Chapter Eleven points out, they helped to obliterate the values of an "old world" peasantry which viewed land as sacred and simultaneously strengthened the Western imperative of human dominion over Nature.<p>
Chapter Twelve discusses the industrialization of agriculture in Robert Stead's Grain (1926). It points out that although Stead was critical of the greed and materialism that accompanied Western settlement, his novels reflect the anthropocentrism endemic to early prairie fiction. It looks at Stead's treatment of the homesteader's "sacred" mission to subdue the earth. It examines the historical context in which Grain is situated, and it discusses Stead's ambivalent--although ultimately favourable--response to the phenomenon of farm mechanization.<p>
Chapter Thirteen contrasts Western man's quest for wealth and power with woman's oppositional quest for healing community. Using Martha Ostenso's Wild Geese (1925), Arthur Stringer's Prairie trilogy (1915-22) and representative fiction of Nellie McClung (1908-25) as texts, it explores the way in which these writers privilege nurturing relationships above the exploitative relationships that characterize prairie agriculture. Stringer's heroine condemns her husband's obsession with money and power, and proposes an alternative ideology based upon love of family and home. Ostenso's Judith Gare rebels against patriarchal tyranny. McClung's protagonists serve as compassionate caregivers who view the land as a resource that provides sustenance--not wealth--for its human inhabitants. In their common opposition to an androcentric culture based on power over women and the land, these novels portray the feminine quest for healing community and for harmony between humans and their prairie home.<p>
Chapter Fourteen looks at two examples of early prairie realism--Frederick Philip Grove's Settlers of the Marsh (1925) and Our Daily Bread (1928). It discusses Grove's love for the prairie landscape, his admiration for the self-sufficient man of the soil, his distaste for economic ambition and his tragic view of life. It contrasts the tragic realism of Our Daily Bread with the comic spirit of reconciliation in Settlers of the Marsh, and suggests that the latter proves better adapted than tragedy as a form in which to cast the heroes' quest for nurturing community. <p>The Conclusion examines the role of the critic as social prophet and revisionary historian. It discusses the role of myth in influencing the course of history, summarizes the cultural impact of the myth of progress created by the wilderness and homesteading romance, notes the existence--and importance--of an oppositional quest for a harmonious relationship with the land, and reviews the role of bioregionalism, deep ecology and ecofeminism in providing the philosophical basis for a sustainable culture appropriate to the prairie bioregion. It considers the responsibility of both homesteaders and turn-of-the-century business entrepreneurs for current environmental degradation, and concludes that the dominant interests of urban politicians, consumers and business people have always been the impetus to agricultural expansion and the continuing depletion of prairie soils.
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Viral ecology of lakes : a descriptive and ecological study of viruses that infect phytoplanktonClasen, Jessica Liz 05 1900 (has links)
Since the 'discovery' of the high abundance of viruses in aquatic environments, it has been generally assumed that viruses in lakes are similar to those in oceans. I directly compared these two systems using a large, robust data set. Viral abundance was significantly different among the surveyed environments. The relationship between viral and bacterial abundance indicated a fundamental difference between lakes and oceans, and suggested that viruses infecting phytoplankton may be more important in lakes.
Molecular techniques (PCR & DGGE) were used to document spatial and temporal variations in the richness of viruses that infect eukaryotic phytoplankton (Phycodnaviridae) in lakes at the Experimental Lakes Area (ELA). Phycodnavirus richness was highest in the eutrophic lake, and during the spring/early summer in all the lakes. Viral richness was closely associated with phytoplankton abundance and composition. As a result, richness was influenced by trophic status, while patterns of richness were affected by regional climatic conditions.
Phylogenetic analysis of environmental Phycodnavirus DNA polymerase (pol) sequences indicated that freshwater Phycodnaviruses are genetically different from cultured isolates and marine environmental sequences. A genetic distance analysis indicated that pol sequences > 7 % different infected different host species. Therefore, the 20 different freshwater sequences likely infected nine different hosts. Multivariate statistics identified seven possible phytoplankton hosts, including chlorophytes, chrysophytes, diatoms and dinoflagellates.
Finally, the modified dilution experiment was evaluated as an approach for estimating viral-mediated phytoplankton mortality in two lakes at the ELA. Experiments resulted in non-significant apparent growth rate regressions. While a model analysis, indicated that the method was sensitive to poorly constrained parameters such as burst size and length of the lytic cycle, making it unsuitable for estimating mortality rates in these lakes.
These studies indicate that Phycodnaviridae are a genetically rich and dynamic component of lakes. Their richness is influenced by both the chemical and physical components of their environment. Although the presence of these viruses indicates that they are a source of phytoplankton mortality, the magnitude of their impact on structuring phytoplankton communities awaits methodological advances. Nonetheless, these findings support the view that viruses infecting phytoplankton are ecologically important components of lake ecosystems.
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Monitoring and prediction of ecological succession by measurement of functional characteristics of soilHill, Thomas C. J. January 1995 (has links)
No description available.
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Valuation of non-timber forest products : a case study for three Amerindian villages in GuyanaSullivan, Caroline January 1999 (has links)
No description available.
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Integrated coastal management in the tropics : identifying the impediments and evaluating management toolsWestmacott, Rachel Susan January 2001 (has links)
Tropical coastal resources including coral reefs, mangroves and seagrass beds are some of the most productive ecosystems in the World. They support a variety of goods and services that may often form the backbone of the local community. In many cases they provide the main source of food, as well as providing employment and recreation opportunities. However, coastal ecosystems are increasingly under threat from high population growth rates, rapid coastal development, over exploitation of the resources, loss of critical habitats and vulnerability to natural hazards. These tropical ecosystems are sensitive and vulnerable to damage and environmental change. Their worldwide loss has led to cause for concern and widespread calls for improved management. Integrated coastal management (ICM) is seen as the way forward in dealing with this complex mix of interests, activities and demands being placed on today's coastal zones. The definition of the coastal zone will vary between locations, ideally capturing and enabling the resolution of all major coastal issues, reaching as far inland or seaward as is required to reach the goals and objectives of the management programme. ICM encompasses the management of all aspects of the coastal zone taking a multi-disciplinary approach. It includes the management of existing economic activities, planned developments, natural resource conservation and utilisation as well as being able to deal with the different user conflicts. ICM involves the integration of different institutions and stakeholder groups at and across the local to international management levels. Even though ICM efforts are increasing, there are few examples where it is really being implemented and working effectively. In this study, three ICM case studies identified similar patterns of impediments although their scope was recognised as too narrow to make generalisations. As a result, a survey was developed to build up a broader picture of the issues blocking the development of successful ICM at several locations. The survey identified the current status of ICM in the tropics and identified the main impediments to implementing effective ICM. The survey found that few locations were actually implementing, monitoring and evaluating ICM, however a number were in the process of it. It was the step between analysis and implementation that was halting many of these efforts. Tropical coastal zones can be seen to share a number of common challenges exacerbated by poverty and conflicts between coastal users. Conflict management needs to be incorporated into the management process in a way that pays particular attention to the over-extraction of resources and destructive resource use. Although the concept of integrated coastal management (ICM) has been identified as the way to deal with the multiple objectives, interests and uses of the coastal zone, in practice it is a complex process and many countries are having difficulty in implementing ICM. The most common impediments to ICM in the tropics were identified through the survey as were their impact on implementing ICM. The extent to which ICM is achieved can be linked to the impediments, described by a series of criteria, which could be used in assessing the ability of an area to implement ICM as well as identifying priority areas for concern. The results show that although public participation is commonly accepted as a major part of ICM and is one of the main impediments, it is rarely fully realised. Gaining political support and empowering agencies with sufficient authority to enforce ICM were also identified as major impediments, without which ICM efforts may well be blocked. Decision making for integrated coastal managementin volves multiple decision makers and multiple stakeholders, often with conflicting needs and interests. Decision support systems (DSS) can be developed to improve our understanding of the inter-relationships between the natural and socioeconomic variables and hence result in improved decision making. The question is whether this decision making environment is actually too complex for the development of useful and useable decision support systems. An ICM-DSS needs to be able to involve multiple decision makers and take into consideration multiple issues. This requires different disciplines to be drawn together into an integrated modelling framework. There are many techniques available to deal with different modelling needs, the constraints of inadequate data and the multi-objective decision making environment. There are also different ways of developing decision support systems and each can play a different, but nonthe- less important role within ICM. Three coastal DSSs were evaluated in terms of their design and roles in integrated coastal management and are used to evaluate the potential to develop ICM-DSSs. One of these DSSs, CORAL, is examined in detail as a case study. The model is an example of an integrated ICM model where the final result is a score-card of criteria that measure economic, environmental, social and institutional objectives. CORAL was developed for the island of Curacao in the Caribbean and the Republic of the Maldives. The development process involved stakeholder meetings and interviews to ensure that all their interests and concerns in the coastal zone were accounted for and included in the DSS. The model development was carried out in the Netherlands and on return was presented to the stakeholder groups. A second phase of the project in Curacao allowed the model to be installed on a wide number of computers. An ICM course was established as well as individual training given to the stakeholder groups involved. However, the final use of the DSS was still limited. Lessons are drawn from the CORAL experience that may assist in the development of future DSSs such as the need to involve a key organisation in the development and enable them to continue its development and maintenance after the end of the project. In addition, flexibility, adaptability and update-ability are paramount if the system is to be used beyond educational goals. The impact of ICM on a coastal system is not always readily measured and quantified, least of all in monetary terms. Economic valuation is being increasingly applied to tropical coastal ecosystems to assess their benefits in monetary terms. From the point of view of ICM, economic valuation could give monetary values to, for example, changes in production resulting from management and hence highlights the importance of management. Likewise, it can highlight the costs of inaction by quantifying the benefits of a situation with ICM and one without ICM. This not only requires the ability to link monetary values to certain environmental situations but also to model the potential changes in goods and services provided by the ecosystem as a result of management. Past analyses in ICM have often focused on the costs of management versus economic gains while change to the environment has been measured in physical terms. Economic valuation provides a potential to compare like with like and hence bring the importance of ecosystems, such as coral reefs, to the fore. Some goods provided by these coastal ecosystems are marketed and consequently have a marketdefined value associated with them. However, these ecosystems also provide a number of non-use benefits, which are not directly marketed and as a result, certain economic techniques have been developed to deal with these issues. The contingent valuation methodology (CVM) was developed as a tool to measure non-marketed goods and services of ecosystems so they can be included into costbenefit analyses. However, it is a complex technique surrounded by much controversy.
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