The influence of the Environmental Quality Incentives Program on local water quality
研究量化了美国环境质量激励计划（EQIP）对全国水质的影响，发现该计划降低了生化需氧量和氮含量，但增加了总悬浮固体、粪大肠菌群和磷，表明部分保护措施可能加剧了土壤侵蚀和病原体转移。
Abstract The Environmental Quality Incentives Program (EQIP) is the primary conservation program on working agricultural land. The United States Department of Agriculture obligated over $15 billion through EQIP cost‐sharing contracts during the fiscal years 2009–2019. The voluntary nature of the program and the lack of performance assessment have led to speculations regarding the effectiveness of the program in delivering environmental benefits, in particular for improving water quality. This study provides quantitative estimates of the influence of EQIP payments on local water quality at a national scale. We link monitoring station level water quality readings with EQIP contract data and exploit the direction of river flow for identification. The estimated effects of EQIP vary across water quality measures. Estimates indicate that EQIP payments have significantly reduced biochemical oxygen demand and nitrogen, indicating improvements in water quality, but increased total suspended solids, fecal coliform, and phosphorus, suggesting that the implementation of certain conservation practices might have increased soil erosion and pathogen transfer, especially in watersheds with more agricultural production.