American Economic Review · 2022 · Charles A. Taylor、Hannah Druckenmiller
中文摘要
2020年，美国环境保护署缩小了“美国水域”的定义范围，大幅限制了《清洁水法》对湿地的保护。当前的政策争论聚焦于湿地效益的不确定性。我们利用详细的洪灾理赔和土地利用数据，估计了美国各地湿地在减轻洪灾方面的价值。我们发现，2001年至2016年间损失的湿地，平均每公顷每年给社会造成1,840美元的成本；在已开发地区，这一成本超过8,000美元。我们揭示了湿地效益存在显著的空间异质性，这对洪灾保险政策以及面临失去联邦保护风险的50%的“孤立”湿地具有启示意义。
Abstract
In 2020 the Environmental Protection Agency narrowed the definition of “waters of the United States,” significantly limiting wetland protection under the Clean Water Act. Current policy debates center on the uncertainty around wetland benefits. We estimate the value of wet-lands for flood mitigation across the United States using detailed flood claims and land use data. We find the average hectare of wetland lost between 2001 and 2016 cost society $1,840 annually, and over $8,000 in developed areas. We document significant spatial heterogeneity in wetland benefits, with implications for flood insurance policy and the 50 percent of “isolated ” wetlands at risk of losing federal protection. (JEL K32, Q24, Q25, Q53, Q58)