Cost-effective targeting of conservation activities has only recently been addressed by economists. Most work to date has focused on finding the best locations to set aside land for the protection of biodiversity. An economic approach to the problem, where biodiversity reserve networks are delineated to maximize the number of species protected subject to a budget constraint, has been shown to be much more cost-effective than the standard approach, where reserve networks are delineated subject to an area constraint, ignoring differences in costs across sites. This paper is among the first to use spatially explicit models of production functions for ecosystem services in an optimization framework for prioritizing sites for wetlands restoration. Tradeoffs between two classes of environmental benefits from wetlands restoration, habitat, and water quality were assessed in the Central Valley of California. Habitat benefits were estimated by a count regression model that relates breeding mallard abundances to the configuration of land use types in the study area, and water quality benefits were estimated by a spatially distributed model of nonpoint source pollution and nutrient attenuation in wetlands. Two decision scenarios were analyzed. In the first scenario the optimal configuration of restoration activity was determined for a small watershed, and in the second scenario sites were selected from those offered for enrollment in an easement program throughout the valley. The results reveal the potential for gains in effectiveness from spatial targeting, and they suggest that there will be substantial tradeoffs between environmental benefits. Maximizing habitat quality in the small watershed yielded a 34% increase in mallard abundance and a 3% decrease in nitrogen loads to the river. In contrast, maximizing water quality resulted in a 25% decrease in nitrogen loads and a 2% increase in mallard abundance. Qualitatively similar results were obtained when sites were selected from a set of offered sites throughout the valley, but the tradeoffs were not as severe. The results also suggest that at traditional funding levels the Wetlands Reserve Program in California could reduce nitrogen loads to rivers by approximately 29,000 kg and increase total mallard abundance in the breeding season by approximately 150 individuals throughout the Central Valley in a given year.

直到最近，经济学家才开始强调保护活动的成本效益目标。迄今为止，大多数工作都集中在寻找最佳地点，留出土地保护生物多样性。经济的解决问题的方法,生物多样性保护区网络划定的物种数量最大化保护受到预算限制,已被证明是比标准方法更具成本效益,划定保护区网络受面积限制,跨站点忽视成本的差异。本文是第一批在优化框架中使用生态系统服务的生产功能的空间显式模型来确定湿地恢复的优先位置的论文之一。在加州中央山谷评估了湿地恢复、栖息地和水质两类环境效益之间的权衡。利用计数回归模型估算了研究区野鸭丰度与土地利用类型配置之间的关系，利用湿地非点源污染和养分衰减的空间分布模型估算了水质效益。分析了两种决策方案。在第一种方案中，确定了小流域恢复活动的最优配置，而在第二种方案中，则从整个山谷的地役权项目中选择登记地点。这些结果揭示了空间定位带来的效率收益的潜力，并且它们表明在环境效益之间将会有实质性的权衡。通过提高小流域生境质量，野鸭数量增加了34%，对河流的氮负荷减少了3%。相反，最大化水质可使氮负荷降低25%，使野鸭丰度增加2%。当从整个山谷的一系列提供的地点中选择地点时，得到了定性相似的结果，但权衡不是那么严重。研究结果还表明，在传统的资助水平下，加州湿地保护计划可以减少大约29000公斤的氮对河流的负荷，并在繁殖季节为中央山谷增加大约150只野鸭。