流域横向生态补偿政策的水环境效益评估

基于2000~2019年浙江和安徽26个地级市的面板数据,使用合成控制法定量分析新安江3轮横向生态补偿试点政策对其水环境效益的总体性和结构性影响结果表明:政策效果在时间上存在异质性。第1、2轮政策试点显著的提升了新安江流域整体的水环境,但第3轮试点对上游水环境的影响是负的。政策效果在空间上存在异质性。流域横向生态补偿政策使下游的生物多样性价值平均提高了0.068亿元，但使上游生物多样性价值平均降低了0.015亿元。政策效果在结构上存在异质性。通过对水环境效益的结构性分解,发现横向生态补偿政策使新安江流域的水质净化能力价值平均提高了31.874亿元，但使其产品供给价值平均下降了13.402亿元。政策效果存在预期效益。流域横向生态补偿的政策效果在政策正式实施前2年已经出现。

Effects of river basin horizontal ecological compensation on water environment benefits

Based on the panel data of 26 prefecture-level cities in Zhejiang and Anhui provinces from 2000 to 2019, this paper uses the synthetic control method to quantitatively analyze the overall and structural impacts of the three-round horizontal ecological compensation pilots’ policy on the Xin'an River basin on its water environmental benefits. The results showed that: (1) there existed temporal heterogeneity in policy effects. The first and second rounds of policy pilots significantly improved the overall water environment of the Xin'an River Basin, while the third round of pilots had a negative impact on the upstream water environment. (2) there existed spatial heterogeneity in policy effects. The horizontal ecological compensation policy of the river basin increased the biodiversity value of the downstream by an average of 6.8 million yuan, but reduced the biodiversity value of the upstream by an average of 1.5 million yuan. (3) there existed structural heterogeneity in policy effects. Structural decomposition of water environmental benefits showed that the horizontal ecological compensation policy increased the value of water purification capacity in the Xin'an River Basin by an average of 3.1874 billion yuan, but reduced the value of its product supply by an average of 1.3402 billion yuan. (4) there existed expected benefits in policy effects. The effect of the horizontal ecological compensation policy has appeared two years ahead the official implementation of the policy.