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21.
Abstract: The alarming pace of tropical biodiversity loss requires development of innovative approaches for in situ biodiversity conservation. Incentive-based approaches have emerged as one possible option. We interviewed 68 private nature reserve owners to learn more about one of Costa Rica's incentive programs. The interview group included all reserve owners participating in the government's Private Wildlife Refuge Program (n = 22) and a control group of nonparticipating owners (n = 46). Quantitative and qualitative data led to seven main conclusions on the use of incentive programs: (1) a developing country can expand and enhance its formal park system through conservation incentives; (2) insufficient promotion, and resulting information gaps, can prevent an incentive program from realizing its full potential; (3) landowners enter a program not only in response to the intended incentive package, but also for several powerful and hidden incentives such as publicity and marketing purposes; (4) underutilization of official incentives by participants, in part due to sporadic delivery of incentives by the government, can undermine program effectiveness; (5) biodiversity protection goals can be accomplished by means of a wide range of incentives; (6) programs that require only a short-term commitment by landowners can still lead to long-term biodiversity protection; and (  7) a program can produce unanticipated negative consequences at the national level, including putting conservation at odds with social justice. These and other lessons on the use of incentives should be of interest wherever biodiversity is threatened, wherever new conservation partners are being sought, and wherever incentive-based approaches are being considered.  相似文献   
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In order to take account of the congestion externalities associated with increased use intensity during a given period at a low density recreational resource, it is necessary to determine the effects of alternative use levels on the expected quality of each individual's experience. This paper describes a simulation model for wilderness recreation designed to provide such measures. In order to illustrate the model it is applied to the Spanish Peaks Areas in Montana.  相似文献   
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This article summarizes a long‐term study of vapor intrusion mitigation system performance in a historic, unoccupied residential duplex with an extensive set of temporal variability observations. The experimental design included multiple cycles of subslab depressurization (SSD) system operation and shut‐off during a seven‐month period, followed by a year‐long period of continuous operation. Results showed that the system provided rapid pressure field extension and radon control as much as 100 days of operation before optimum volatile organic compound (VOC) mitigation was achieved. Greater variability in VOC concentrations than in radon concentrations was observed during the initial mitigation system cycling. Subslab VOC concentrations at numerous locations increased during this initial period of SSD operation, and indoor air VOC concentrations were more variable than radon. However, indoor air concentrations were considerably less variable (and lower) during the first year of continuous mitigation system operation. ©2015 Wiley Periodicals, Inc.  相似文献   
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Phytoremediation, the use of plants for in situ contaminant cleanup, is gaining new appreciation as an aesthetically pleasing, sustainable method that naturally makes use of solar power. Hybrid poplars are widely used because they grow rapidly and have high transpiration rates, making them advantageous for hydraulic control of groundwater. However, the tendency for trees and other vegetation to uptake metals may be a disadvantage in some settings due to potential redistribution of metals from groundwater to the ground surface. Therefore, a pilot test in the upper midwestern United States was implemented to evaluate the applicability of poplars to groundwater withdrawal and metals transport. © 2009 Wiley Periodicals, Inc.  相似文献   
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Smallholder farmers in sub-Saharan Africa are confronted with climatic and non-climatic stressors. Research attention has focused on climatic stressors, such as rainfall variability, with few empirical studies exploring non-climatic stressors and how these interact with climatic stressors at multiple scales to affect food security and livelihoods. This focus on climatic factors restricts understanding of the combinations of stressors that exacerbate the vulnerability of farming households and hampers the development of holistic climate change adaptation policies. This study addresses this particular research gap by adopting a multi-scale approach to understand how climatic and non-climatic stressors vary, and interact, across three spatial scales (household, community and district levels) to influence livelihood vulnerability of smallholder farming households in the Savannah zone of northern Ghana. This study across three case study villages utilises a series of participatory tools including semi-structured interviews, key informant interviews and focus group discussions. The incidence, importance, severity and overall risk indices for stressors are calculated at the household, community, and district levels. Results show that climatic and non-climatic stressors were perceived differently; yet, there were a number of common stressors including lack of money, high cost of farm inputs, erratic rainfall, cattle destruction of crops, limited access to markets and lack of agricultural equipment that crossed all scales. Results indicate that the gender of respondents influenced the perception and severity assessment of stressors on rural livelihoods at the community level. Findings suggest a mismatch between local and district level priorities that have implications for policy and development of agricultural and related livelihoods in rural communities. Ghana’s climate change adaptation policies need to take a more holistic approach that integrates both climatic and non-climatic factors to ensure policy coherence between national climate adaptation plans and District development plans.  相似文献   
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A variety of models for predicting the behaviour of radionuclides in fresh water ecosystems have been developed and tested during recent decades within the framework of many international research projects. These models have been implemented in Computerised Decision Support Systems (CDSS) for assisting the appropriate management of fresh water bodies contaminated by radionuclides. The assessment of the state-of-the-art and the consolidation of these CDSSs has been envisaged, by the scientific community, as a primary necessity for the rationalisation of the sector. The classification of the approaches of the various models, the determination of their essential features, the identification of similarities and differences among them and the definition of their application domains are all essential for the harmonisation of the existing CDSSs and for the possible development and improvement of reference models that can be widely applied in different environmental conditions. The present paper summarises the results of the assessment and evaluation of models for predicting the behaviour of radionuclides in lacustrine ecosystems. Such models were developed and tested within major projects financed by the European Commission during its 4th Framework Programme (1994-1998). The work done during the recent decades by many modellers at an international level has produced some consolidated results that are widely accepted by most experts. Nevertheless, some new results have arisen from recent studies and certain model improvements are still necessary.  相似文献   
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The intent of this paper is to place the concepts of exposure, vulnerability, resilience and risk in the context of the consequences of global change for the sustainable development of small island developing states (SIDS). Many such states face a number of global climate change risks, such as an increase in the proportion of more intense storms, along with other global change threats that include energy security and costs. All these threats come on top of local development threats, such as increased run-off, often with increasing levels of contaminants due to unsustainable agricultural and industrial practices. When taken together, the resulting pressures on islands and their communities lead to significant increases in vulnerability to change due to reduced resilience to these changes. Vulnerability is also increasing as a result of contemporary processes that heighten the exposure of material and other assets. The capacity to address hazard risk also influences vulnerability. This includes the level of awareness of coastal hazards and exposure, and access to critical life support infrastructure, especially for people living in hazard-prone areas. Vulnerability and resilience are considered to be important integrating concepts when managing the local consequences of global changes. There are many initiatives that will help reduce the vulnerability and enhance the resilience of SIDS to such changes. These include improving risk knowledge and coastal resource and land use management, while also strengthening socio-economic systems and livelihoods. In this way, managing global change can be closely aligned with local development and humanitarian processes, thereby enhancing the overall sustainability of development processes and outcomes.  相似文献   
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