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41.
Qiu Z 《Environmental management》2003,32(3):299-311
Conservation buffers have the potential to reduce agricultural nonpoint source pollution and improve terrestrial wildlife habitat, landscape biodiversity, flood control, recreation, and aesthetics. Conservation buffers, streamside areas and riparian wetlands are being used or have been proposed to control agricultural nonpoint source pollution. This paper proposes an innovative strategy for placing conservation buffers based on the variable source area (VSA) hydrology. VSAs are small, variable but predictable portion of a watershed that regularly contributes to runoff generation. The VSA-based strategy involves the following three steps: first, identifying VSAs in landscapes based on natural characteristics such as hydrology, land use/cover, topography and soils; second, targeting areas within VSAs for conservation buffers; third, refining the size and location of conservation buffers based on other factors such as weather, environmental objectives, available funding and other best management practices. Building conservation buffers in VSAs allows agricultural runoff to more uniformly enter buffers and stay there longer, which increases the buffers capacity to remove sediments and nutrients. A field-scale example is presented to demonstrate the effectiveness and cost-effectiveness of the within-VSA conservation buffer scenario relative to a typical edge-of-field buffer scenario. The results enhance the understanding of hydrological processes and interactions between agricultural lands and conservation buffers in agricultural landscapes, and provide practical guidance for land resource managers and conservationists who use conservation buffers to improve water quality and amenity values of agricultural landscape. 相似文献
42.
In this paper, we study empirically whether uncertainty has an influence on trade in the US sulfur dioxide allowances market.
In particular, we investigate the role of uncertainty on banking behavior. To do this, we introduce a tractable, structural
model of trading permits under uncertainty. The model establishes a relation between banking behavior and risk preferences,
especially prudence in the Kimball (1990) sense. We then test this model using data on allowances, for utilities submitted to the US Environmental Protection Agency’s
Acid Rain Program, carried over from one year to the next. Evidence is found of imprudence, namely, utilities bank permits
in order to favor higher profits. Another finding is that larger utilities do not adopt behavior significantly different from
that of smaller ones.
This paper was presented at the “International Workshop on Uncertainty in Greenhouse Gas Inventories: Verification, Compliance
& Trading” in Warsaw, Poland, September 2004, under the title “Portfolio Management of Emissions Permits and Prudence Behavior.” 相似文献
43.
A study was carried out in Nova Scotia, Canada, to experimentally assess the effect of snowmobiles on old field and marsh vegetation. Snowmobile treatments ranging from a single pass to 25 passes (five passes on five separate days) were administered. The first pass by a snowmobile caused the greatest increase in snow compaction-roughly 75% of that observed after five sequential passes. Snowmobile treatment resulted in highly significant increases in snow retention in spring. Frequency was more important than intensity in this regard.Standing crop and species composition were measured the following summer. Standing crop in the field showed a significant reduction with increasing snowmobile use; frequency of treatment (p < 0.01) was more important than intensity (p = 0.125).Stellaria graminea, Aster cordifolius, Ranunculus repens, andEquisetum arvense all showed significant (p < 0.05) differences in percent cover resulting from the treatment. Marginally significant changes were observed inAgrostis tenuis andPhleum pratense Marsh vegetation showed no significant effects of snowmobile treatment. This may have been because of solid ice cover during the winter.The literature is critically reviewed. It is concluded that snowmobile use can have a highly significant effect upon natural vegetation. Management suggestions are made. 相似文献
44.
There is an urgent need to develop sound theory and practice for biodiversity offsets to provide a better basis for offset multipliers, to improve accounting for time delays in offset repayments, and to develop a common framework for evaluating in-kind and out-of-kind offsets. Here, we apply concepts and measures from systematic conservation planning and financial accounting to provide a basis for determining equity across type (of biodiversity), space, and time. We introduce net present biodiversity value (NPBV) as a theoretical and practical measure for defining the offset required to achieve no-net-loss. For evaluating equity in type and space we use measures of biodiversity value from systematic conservation planning. Time discount rates are used to address risk of non-repayment, and loss of utility. We illustrate these concepts and measures with two examples of biodiversity impact–offset transactions. Considerable further work is required to understand the characteristics of these approaches. 相似文献
45.
How conservation messages are framed will impact the success of our efforts to engage people in conservation action. This is highly relevant in the private land conservation (PLC) sector given the low participation rates of landholders. Using a case study of PLC schemes targeted at Australian landholders, we present the first systematic analysis of communication strategies used by organisations and government departments delivering those schemes to engage the public. We develop a novel approach for analysing the framing of conservation messages that codes the stated benefits of schemes according to value orientation. We categorised the benefits as flowing to either the landholder, to society, or to the environment, corresponding to the egoistic, altruistic and biospheric value orientations that have been shown to influence human behaviour. We find that messages are biased towards environmental benefits. Surprisingly, this is the case even for market-based schemes that have the explicit objective of appealing to production-focussed landholders and those who are not already involved in conservation. The risk is that PLC schemes framed in this way will fail to engage more egoistically oriented landholders and are only likely to appeal to those likely to already be conservation-minded. By understanding the frame in which PLC benefits are communicated, we can begin to understand the types of people who may be engaged by these messages, and who may not be. Results suggest that the framing of the communications for many schemes could be broadened to appeal to a more diverse group (and thus ultimately to a larger group) of landholders. 相似文献
46.
New York City’s extensive municipal park system is home to forests, wetlands, and grasslands that provide important ecological and social benefits to the city’s population. While efforts and programs exist to restore and protect these spaces, management recommendations are complex due to variable conditions in urban natural areas. To advance the management of urban natural areas, the first comprehensive ecological assessment was conducted through a collaborative effort across 4000 ha of natural areas within New York City parkland. Field and spatial data were collected and analyzed to identify the extent of forests, the types of forests, and their conditions. This approach will help guide decision-making and prioritization of natural area management at the regional level by developing unique quantitative targets for urban forests. This project serves as an example of collaboration between private and public institutions advancing the governance of urban natural areas to achieve citywide conservation and policy goals. 相似文献
47.
Reed MG 《Environmental management》2007,39(1):30-49
Advocates of community-based approaches to environmental management argue that by respecting local circumstances, skills,
and concerns we may improve the prospects of achieving environmental sustainability; yet, within nation states such as Canada,
environmental conditions, management and enforcement costs and capabilities, and power differentials within and among civic
and public sectors may result in a highly differentiated capacity for environmental management across different localities
and regions. This article draws on insights of political ecology to 1) create a conceptual framework that identifies key elements
shaping regional environmental management regimes and to 2) undertake a comparative analysis to assess how elements interact
to generate uneven management outcomes. I compare experiences of two Canadian biosphere reserves designated in 2000: Clayoquot
Sound, BC; and Redberry Lake, SK. Analysis reveals that differences in governance and institutional capacities in the biosphere
reserves are key to explaining uneven local outcomes. Where the public and civic sectors are strong, a robust and publicly
vetted form of management will emerge. Where these sectors are weak and land is held as private property, environmental nongovernmental
organizations can set the type and level of management, to the exclusion of effective civic and state involvement. This result
may improve environmental sustainability but hinder social sustainability of a management regime and raises questions about
the efficacy of community-based management. 相似文献
48.
Current political conditions, primarily budgetary uncertainty, and the related reluctance to make funding commitments for
future generations, have raised questions about the costs of conservation and environmental protection that have not previously
been asked. As Federal investments are scrutinized and budgets become ever more constrained, the costs associated with environmental
requirements could begin to be of greater importance and to influence decisions on Federal projects. In response to concerns
about the U.S. Army Corps of Engineers (Corps) spending under the Endangered Species Act (P.L. 93-205) (ESA), a limited investigation
was performed to determine the accuracy of reported Corps expenditures. The investigation showed that, for particular groups
of species, actual conservation costs for threatened and endangered species may be twice the amounts previously reported in
the annual ESA expenditure reporting to the U.S. Fish and Wildlife Service. In light of this finding, the Corps has sought
a means to provide more accurate and consistent reporting of expenditures for addressing threatened and endangered species.
A Species Costs Template (template) has been developed to identify the types and magnitude of costs related to the ESA and
to counteract the impediments (legal, institutional, and practical) to underreporting costs. The template will be used by
the Corps for reporting ESA costs beginning with Fiscal Year 2005 (FY05) (reported in January 2006). Five broad categories
of expenditures (effects determination costs, ESA protection and conservation costs, equipment costs, opportunity costs, and
other species costs) are identified by the template. 相似文献
49.
The expectations on protected areas to deliver not only biodiversity conservation but also to provide an array of different ecosystem services rise. Sequestration and storage of carbon are promising services that protected areas may provide. This study integrates spatially explicit data on terrestrial Natura 2000 sites, soil organic carbon, and agricultural land values to estimate the potential for climate-smart conservation planning in the European Union. The objectives of this study are to analyse spatial relations between protected areas soil carbon content, and land values on the European Union's land area as well as to locate and quantify the proportion of land with high carbon and low economic value within and outside protected areas. We apply a unique interdisciplinary framework with methods ranging from analyses based on geographical information systems, agricultural economics to statistics. Findings indicate that there is a significant overlap between Natura 2000 sites and regions with high carbon content across Europe. Statistical analyses show that carbon-rich regions have significantly lower land values than other areas. Our results suggest that biodiversity protection and mitigation of climate change through conservation of soil carbon could be simultaneously achieved in Europe's protected areas and beyond. We conclude that there is a notable potential for climate-smart conservation in Europe that needs further investigation. 相似文献
50.
As resource conservation is an imperative for sustainable development, it is crucial to achieve a deeper understanding of the factors involved in people's decisions to recycle. This is even more so because the level of environmental concern is usually higher than the level of ecological behaviours. In this paper we take this fact as indicating that decision-making regarding conservation behaviours happens in the context of an internal debate where contradictory ideas are weighed up and the possibility of ambivalence arises. The main aim of this paper is therefore to explore how contradiction and ambivalence impact upon the attitudes, intentions and pro-ecological behaviours of the private sphere. The paper focuses specifically on the separation and deposition of metal cans, and compares the predictive capacity of beliefs, attitudes and intentions for two groups of respondents – one with a high and another with a low level of ambivalence, as assessed with a direct measure. The role of personal identity and the influence of structural constraints are also explored. Results demonstrate a clear moderating effect of experienced ambivalence, and show how beliefs, particularly negative ones, present a higher predictive capacity of the attitude in the high-ambivalence group, and personal identity plays a relevant role in predicting behaviour in both groups. We discuss the importance of pursuing the study of ambivalence when analysing decision-making in the conservation area. 相似文献