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The sub-discipline of Political Ecology devotes much critical attention to the complex and often pernicious socio-ecological impacts of mainstream development - developmentality - across the world. However, despite the ’ecology’ in its name, Political Ecology continues to be predominantly anthropocentric which, we contend, compromises its critique of developmentality’s excesses. Drawing on recent literatures in philosophy, political theory, and human geography, we argue that both the more-than-human and social impacts of developmentality are enabled by zoöpolitical logics of human exceptionalism which support anthropocentrism. We suggest that the adverse effects of development are co-constituted with the positive vision of human wellbeing which runs through developmentality. Thus, an effective critique of development will necessarily have to address the zoöpolitical logics that underpin anthropocentrism. Doing so will strengthen the rigour of political ecology’s engagement with developmentality and widen its attention to the diversity of life harmed by mainstream development.  相似文献   

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The need to view human activity as an integral component of the geosphere-biosphere system has been emphasized since the earliest writings on global environmental change. In recent years, however, the long-term, large-scale interactions between human activities and the world's environment have become the focus of increasing practical and scholarly attention. Several national and international programs are beginning to plan systematic research strategies for better understanding those interactions. This paper attempts to review and summarize the major conclusions of these early planning efforts through a discussion of the major unresolved questions relating to the human ecology of global change.  相似文献   

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Epilogue: Towards a future for political ecology that works   总被引:2,自引:0,他引:2  
Piers Blaikie 《Geoforum》2008,39(2):765-772
Political Ecology (PE) has been retrospectively created from a history of wide ranging work of different disciplines, cultural settings and epistemological foundations. Its conceptualization was and remains expansive, eclectic and inclusive which has brought both innovative thinking and charges of incoherence. A review of these paradoxical views on the quality of knowledge and its effectiveness in promoting justice and other aspects of political progress concludes that PE can fulfil these criteria in spite of challenges involved in understanding an exceptionally wide range of different disciplines in the natural and social sciences, technical detail and cultural settings. Also, the production of PE both shapes and is shaped by the structures of the academy and daily practice of teaching and research in a reflexive way. There are particular rewards and penalties in academic production which make it difficult to undertake long term PE research, to write overall integrative PE work other than edited and multi-author works, and to engage with wider audiences outside the academy. There is also an enduring stand-off between PE and policy matters. The growth of PE courses in anglophone universities is encouraging more comparison, coherence and communication between political ecologists and promises increasing stabilization and legitimacy of the field.  相似文献   

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Despite the widespread incorporation of sustainable development into policy discourses, actually achieving the ‘win-win-win’ scenario of economic, environmental and social development continues to be problematic. Advocates of industrial ecology suggest that by shifting the basis of industrial production from a linear to a closed loop system, these gains can be achieved. In recent years, concepts drawn from industrial ecology have been used to plan and develop eco-industrial parks (EIPs) that seek to increase business competitiveness, reduce waste and pollution, create jobs and improve working conditions. Despite a growing interest in EIPs, there have been few empirically informed studies that seek to explore the potential contribution such EIPs may make to sustainable development. This paper contributes to a developing sympathetic critique of industrial ecology by focusing on the key problems and dilemmas that arise in the course of developing eco-industrial parks, drawing upon empirical work conducted in the USA. The paper draws upon both an extensive survey of EIPs and in-depth interviews conducted with a range of stakeholders at ten US sites. As the paper reveals, EIPs in the USA are in their early stages and likewise their contribution to both economic development and environmental policy, let alone social policies, is complicated and inchoate. The empirical material reveals that key features of industrial ecology such as inter-firm networking and collaboration in the form of materials interchange and energy cascading are either absent or in the early planning stages. In each of the ten cases what is emerging is a form of EIP partly determined by the geographic setting and broader economic realities of the locality. While collaborative behaviour between firms is central to EIP development if the potential benefits of industrial ecology are to be realised, it is important to realise that such behaviour is difficult to develop from scratch through policy intervention. In conclusion, the paper suggests that expectations must be realistic for the community and location in question. As part of that realism, EIP projects must be designed to allow for a gradual approach, and each phase needs to be financially viable.  相似文献   

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The paleoceanographic-climatic record represented by deep-sea microfossils reflects conditions for only certain times of the year. Also, the relative abundances of microfossil species in deep-sea sediments do not usually reflect only one paleoceanographic variable, such as temperature. Rather, species distributions represent the integration of many factors that control biological production in the oceans. This influences the information on past climates that can be extracted from fossil material. The seasonal limitation is due to the cyclic nature of biological production in the open ocean. Case studies of the sediment record in the Atlantic for two species of planktonic Foraminifera, left-coiling Neogloboquadrina pachyderma (Ehrenberg) and Globigerinoides ruber (d'Orbigny), illustrate seasonal bias in environmental data reported by the relative abundances of species in deep-sea sediments. In addition, the study of G. ruber illustrates the operation of two oceanographic parameters in controlling a species distribution. These examples demonstrate that the environmental signal in the sediments is the result of the interplay of the ecological tolerance of the plankton species with seasonally variable biological and physical properties of the upper ocean.  相似文献   

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Forest ecology suffers from a lack of long-term community records. Preserved pollen data are richer in such information than is generally realized. By applying suitable statistical techniques to pollen records, one can learn much about competition, succession, and population dynamics in past tree communities. In this study, preserved pollen records from Everitt Lake, Nova Scotia, are analyzed as time series. Time domain studies reveal the post-fire responses of individual tree taxa. Correlograms yield models of past forest succession patterns. The models explain some effects of changing fire frequency, thus suggesting mechanisms by which fire, competition, and climate combine to produce long-term forest composition changes. Frequency domain studies suggest relationships between disturbance cycles, stand composition, and forest mosaics. Fire frequencies are seen to be highest where fire-dependent species abound and most regular where tree stands have uniform, not mixed, composition.  相似文献   

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New trends in marine chemical ecology   总被引:1,自引:0,他引:1  
This essay is the outcome of a colloquium convened in November 2005 at the Benthos Laboratory of the Stazione Zoologica Anton Dohrn in Ischia, Italy, on chemical ecology and the role of secondary metabolites in the structuring and functioning of marine biodiversity. The participants of the workshop are part of the European Network of Excellence MarBEF (Marine Biodiversity and Ecosystem Function), a consortium of 56 European marine institutes to integrate and disseminate knowledge and expertise on marine biodiversity. Here we review some of the new trends and emerging topics in marine chemical ecology. The first section deals with microbial chemical interactions. Microbes communicate with each other using diffusible molecules such as N-acylhomoserine lactones (AHL). These are regulators in cell-density-dependent gene regulation (quorum sensing) controlling microbial processes. In chemical interactions with higher organisms, microbes can act either as harmful pathogens that are repelled by the host’s chemical defense or as beneficial symbionts. These symbionts are sometimes the true producers of the host’s secondary metabolites that have defensive and protective functions for their hosts. We also describe how allelochemicals can shape phytoplankton communities by regulating competition for available resources, and also interactions among individuals of the same species. Compounds such as the diatom-derived unsaturated aldehydes have been demonstrated to act as info chemicals, and they possibly function as a diffusible bloom-termination signal that triggers an active cell death and bloom termination at sea. The same molecules have also been shown to interfere with the reproductive capacity of grazing animals deterring future generations of potential predators. Such compounds differ from those that act as feeding deterrents since they do not target the predator but its offspring. Many of the neurotoxins produced by dinoflagellates act as feeding deterrents, and laboratory experiments have shown that ingestion of these algae by some microzooplankton and macrozooplankton can cause acute, responses such as death, incapacitation, altered swimming behavior, and reduced fecundity and egg-hatching success. These effects may rarely occur in nature because of low individual grazing rates on dinoflagellate cells and grazing on other food sources such as microflagellates and diatoms. We also consider the nutritional component of marine plant-herbivore interactions, especially in the plankton, and the information available on the effects of growing conditions of algae on the production of toxic metabolites. Species producing saxitoxins seem to consistently produce the highest amounts of toxins (on a per cell basis) in the exponential phase of growth, and there is a decrease in their production under nitrogen, but not under phosphorus stress, where the production actually increases. We try to explain the circumstances under which organisms defend themselves chemically and argue that the most likely explanatory model for the production of secondary metabolites used for defense in planktonic organisms is the carbon nutrient balance hypothesis, which predicts that most algae produce their toxins mainly under conditions where carbon is in excess and nitrogen (or other nutrients) is limiting. We also discuss chemically mediated macroalgal-herbivore interactions in the benthos and the large variation in concentration of seaweed defense metabolites at different spatial and temporal scales. Seaweeds have been shown to produce a large variety of secondary metabolites with highly variable chemical structures such as terpenoids, acetogenins, amino acid derivates, and polyphenols. Many of these compounds probably have multiple simultaneous functions for the seaweeds and can act as allelopathic, antimicrobial, and antifouling or ultraviolet-screening agents, as well as herbivore deterrents. We also provide examples of interactions between marine benthic invertebrates, especially sponges, molluscs, and cnidarians, that are mediated by specific secondary metabolites and discuss the role of these in shaping benthic communities.  相似文献   

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Numerous phytoplankton-oriented ecological studies have been conducted since 1965 in the extensive North Carolina estuarine system. Throughout a range of geomorphological estuarine types, a basic underlying pattern of phytoplankton productivity and abundance following water temperature seasonal fluctuations was observed. Overlying this solar-driven pattern was a secondary forcing mechanism consisting of a complex interaction between meteorology and hydrology, resulting in periodic winter or early spring algal blooms and productivity pulses in the lower riverine estuaries. Wet winters caused abundant nitrate to reach the lower estuaries and stimulate the blooms, whereas dry winters resulted in low winter phytoplankton abundance and primary production. Dinoflagellates (Heterocapsa triquetra, Prorocentrum minimum, Gymnodinium spp.) and various cryptomonads dominated these cool-weather estuarine blooms. Sounds were less productive than the riverine estuaries, and were dominated by diatoms such asSkeletonema costatum, Thalassiosira spp.,Melosira spp., andNitzschia spp., as were the most saline portions of riverine estuaries. Nutrient-limitation studies found that nitrogen was the principal limiting nutrient in these estuarine systems over a range of trophic states, with phosphorus occasionally co-limiting. Freshwater and oligohaline portions of large coastal plain rivers were often subject to summer blue-green algal blooms. Formation of these blooms on a year-to-year basis was also determined by meteorology and hydrology: wet winters or springs and consequent nutrient loading, coupled with low summer flow conditions and regeneration of nutrients from the sediments. Dry winters or springs resulted in less available nutrients for subsequent summer regeneration, and high flow conditions in summer flushed out the blooms. In recent years, there has been a dramatic increase in reported fish kills attributed to toxic dinoflagellate blooms, particularly in nutrient-enriched estuarine areas. This issue has become a major coastal ecological and economic concern.  相似文献   

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The dominance of “ecosystem services” as a guiding concept for environmental management – where it appears as a neutral, obvious, taken-for-granted concept – hides the fact that there are choices implicit in its framing and in its application. In other words, it is a highly political concept, and its utility depends on the arena in which it is used and what it is used for. Following a political ecology framework, and based on a literature review, bibliometric analyses, and brief examples from two tropical rainforest countries, this review investigates four moments in the construction and application of the ecosystem services idea: socio-historical (the emergence of the discourse), ontological (what knowledge does the concept allow?), scientific (difficulties in its practical application), and political (who wins, who loses?). We show how the concept is a boundary object with widespread appeal, trace the discursive and institutional context within which it gained traction, and argue that choices of scale, definition, and method in measuring ecosystem services frustrate its straightforward application. As a result, it is used in diverse ways by different interests to justify different kinds of interventions that at times might be totally opposed. In Madagascar, the ecosystem services idea is mainly used to justify forest conservation in ways open to critique for its neoliberalization of nature or disempowerment of communities. In contrast, in the Brazilian Amazon, the discourse of ecosystem services has served the agendas of traditional populations and family farm lobbies. Ecosystem services, as an idea and tool, are mobilized by diverse actors in real-life situations that lead to complex, regionally particular and fundamentally political outcomes.  相似文献   

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环形生态水槽流动的特性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
实测了环形生态水槽内的流速分布。采用柱坐标系下的κ-ε湍流模型及SIMPLE算法,对该流场进行了数值模拟。从计算结果和实验资料的分析比较看出,计算结果可靠。在此流场内进行了钉螺的运动特点的实验研究,结果表明钉螺具有流速敏感性,对研究钉螺的随流扩散具有重要意义。  相似文献   

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This essay serves as an introduction to this theme issue of GeoJournal and provides a framework for the contributed papers. Territoriality and scale, the essay argues, offer key analytics in approaching the spatiality of the ecological existence of human and non-human beings in their common `house' (oikos), thus of culture-nature relations generally. Such a focus, it bears emphasis, need not reproduce a naturalization of the modern culture-nature binary, but could, as is argued, remind `we moderns' that there is not only one nature (as little as there is only one culture), but a plurality of natures, which can serve the most varied of purposes. However, these spatialities do usually not and can very often not correspond to the spatialities of human activities, particularly to the territorialities and their orders/structures of scale in politico-administrative activities. The scalar literature within political geography, however, has for the most part seen its role as addressing human social relations in its analysis of contestations over power, space, and territory. A political ecology of scale, by contrast, will of necessity need to broaden the terrain of that discussion to include a variety of actors, human and non-human, involved in this broader network. Environmental conservation offers an important illustration of this problematic. A territorial, scalar, and non-modern understanding of ecological regimes is neccesary, argues this essay and the bundle of case studies that follow, because there is no `conservation' outside of a particular politics and geography of ecology.  相似文献   

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