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排序方式: 共有254条查询结果,搜索用时 500 毫秒
171.
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TOBY A. GARDNER AMREI VON HASE SUSIE BROWNLIE JONATHAN M. M. EKSTROM JOHN D. PILGRIM CONRAD E. SAVY R. T. THEO STEPHENS JO TREWEEK GRAHAM T. USSHER GERRI WARD KERRY TEN KATE 《Conservation biology》2013,27(6):1254-1264
Businesses, governments, and financial institutions are increasingly adopting a policy of no net loss of biodiversity for development activities. The goal of no net loss is intended to help relieve tension between conservation and development by enabling economic gains to be achieved without concomitant biodiversity losses. biodiversity offsets represent a necessary component of a much broader mitigation strategy for achieving no net loss following prior application of avoidance, minimization, and remediation measures. However, doubts have been raised about the appropriate use of biodiversity offsets. We examined what no net loss means as a desirable conservation outcome and reviewed the conditions that determine whether, and under what circumstances, biodiversity offsets can help achieve such a goal. We propose a conceptual framework to substitute the often ad hoc approaches evident in many biodiversity offset initiatives. The relevance of biodiversity offsets to no net loss rests on 2 fundamental premises. First, offsets are rarely adequate for achieving no net loss of biodiversity alone. Second, some development effects may be too difficult or risky, or even impossible, to offset. To help to deliver no net loss through biodiversity offsets, biodiversity gains must be comparable to losses, be in addition to conservation gains that may have occurred in absence of the offset, and be lasting and protected from risk of failure. Adherence to these conditions requires consideration of the wider landscape context of development and offset activities, timing of offset delivery, measurement of biodiversity, accounting procedures and rule sets used to calculate biodiversity losses and gains and guide offset design, and approaches to managing risk. Adoption of this framework will strengthen the potential for offsets to provide an ecologically defensible mechanism that can help reconcile conservation and development. Balances de Biodiversidad y el Reto de No Obtener Pérdida Neta 相似文献
173.
Integrated hydro-economic assessment of restoration of the Alexander-Zeimar River (Israel-Palestinian Authority) 总被引:1,自引:1,他引:0
This paper examines hydro-economic aspects of the Alexander-Zeimar basin. The Alexander-Zeimar River is a transboundary river originating in the Palestinian Authority and flowing through Israel to the Mediterranean Sea. Since the 1950s, the river has been used as a sewage outlet. The major purpose of this study is to estimate the costs and benefits derived from a restoration plan, which has been in place in the river since the mid-1990s. A hydrological model combined with market and non-market valuation (travel cost method) techniques was used to estimate the condition of the situation before and after the restoration project was implemented. The total restoration plan was compared to alternative partial plans. Interestingly, a cost–benefit analysis on the different restoration options revealed that only a complete cleanup of the river results in a positive net benefit ($0.49–3.23 million annually). 相似文献
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Nir Becker K William Easter 《Journal of the American Water Resources Association》1989,25(6):1273-1274
178.
Charles P. Becker Allender M. Griffin Carol S. Lown 《Journal of the American Water Resources Association》1973,9(5):963-975
ABSTRACT: Water resource and water quality management planning depend, to a large degree, on forecasts of industrial activity and population projections. A flexible economic data base is especially important where planning follows varying formats of geographical and industrial detail. Records of employment and payroll are collected in the administration of Unemployment Insurance (U.I.) programs and are available from State Employment Agencies. These statistics have been collected over a long period of record (thirty-five years). Many years of record are available on punched-cards or magnetic tape and may be arrayed and manipulated by computer. This basic approach has been followed in Virginia. Historical U.I. payroll and employment records for the period 1956 through 1970 were procured on magnetic tape. This data was arrayed by major hydrologic area and by regional planning district. Projections of manufacturing activity were then generated by fitting several exponential equations to annual payroll data in two-digit Standard Industrial Classifications. These exponentials were then extrapolated to provide a range of industrial projections. Other parameters of manufacturing activity were then correlated to the payroll data to generate projections of indexes such as employment, value-added, and gross manufacturing output. U.I. payroll data is now being correlated to parameters in non-manufacturing categories. Projections for industries such as trade and services will link extrapolated payroll data with benchmark correlations of payroll and sales receipts. 相似文献
179.
The present study investigated the emissions of naphthalene and other compounds from several different moth repellents(MRs) and one toilet deodorant block(TDB)currently sold in Korea,using a headspace analysis.The emission factors and emission rates of naphthalene were studied using a small-scale environmental chamber.Paper-type products emitted a higher concentration of the total volatile organic compounds(VOCs)(normalized to the weight of test piece)than ball-type products,which in turn emitted higher ... 相似文献
180.