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The English derive a wide range of values from allotments, but nearly 35% of allotments have disappeared in the last 20 years. The real value of allotments has probably been underestimated. The contingent valuation method (CVM) was used to give a monetary value to benefits derived from allotments by allotment holders and local residents. The study was conducted in southeast England (Wye and Ashford, Kent and Greater London). A postal survey with open-ended questions was filled in by 124 allotment holders and 74 residents. Respondents were asked to express their maximum willingness to pay for allotments (WTP) and the minimum willingness to accept (WTA) compensation for loss of allotments. The mean annual WTP for keeping allotments of allotment holders were £78.93, £35.64 and £79.43, and for local residents were £41.66, £46.14 and £283.57, in Wye, Ashford and London, respectively. The allotment holders' WTP was strategically more than WTA compensation and they were only willing to pay rent for using allotments, not for retaining them.  相似文献   
2.
The crop livestock integrated farming system practiced in hilly regions of developing countries largely depends on the ecosystem as a whole. More especifically, the livestock component of the farming system relies heavily on natural resources such as forest, grazing and agricultural land for the supply of feed and fodder. The importance of animals as agents of nutrient recycling, sources of rural energy in terms of draft power and fuel, as well as being major contributors to the farm economy, has resulted in an increased population of ruminants in these regions, creating a threat to the sustainability and productivity of these land resources. This paper is an attempt to evaluate the livestock carrying capacity of land resources and to formulate the optimum herd size compatible with the differently resourced farm categories within the sub-watershed region of the mid-hills in Nepal. Our analysis reveals that the livestock carrying capacity of the land resources at the watershed level is 11696 Livestock Units (LU), whereas current stocking is 12985 LU, suggesting an overstocking of 1289 LU at the watershed level. Total feed supply from different sources is 12668 mt/yr whereas current Total Digestive Nutrient (TDN) demand is 14060 mt/yr, a negative balance of 1393 mt/yr. The excess livestock at the sub-watershed level directly implies excess livestock holding, producing a poor nutritional status for the farm household. Linear programming analysis reveals that the farmers of large, medium and small category farms can optimize their livestock holding by a combination of 3 LU buffaloes and 4 LU goats, 2 LU buffaloes and 4 LU goats and 1 LU buffaloes and 4.4 LU goats, thus giving maximum return to the farm family without exerting pressure on fragile natural resources.  相似文献   
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We have reviewed the development, background and valuation history of ecosystem services in China and abroad, and highlight the importance of ecosystem services and the necessity of their valuation at various temporal and spatial scales. Through critical review of the literature, we have elucidated disadvantages in studies of ecosystem services in China, including the lack of a definite purpose for the valuation of ecosystem services, improper emphasis of valuation studies, stifled application of the contingent valuation method, weak power of research panels in the field, and the absence of the participation of government officials. In addition, we discuss some case studies from Western countries which tracked changes in the total economic value (TEV) of ecosystem services across different states of ecological disturbance and evaluated changes in the TEV under different management regimes. These studies may be useful in guiding future research in China. In essence, there are three major aspects involved in the valuation of ecosystem services: improving accuracy of valuation, association of results of valuation with policy and management decisions, and transfer of payments for ecosystem services. We suggest three priorities for future research in China: to develop an ecosystem service valuation model, to enhance the relevance of valuation studies to policy development, and to reward the protectors of ecosystem services.  相似文献   
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