Selection and calibration of condition variables.

The water resource tax reform played an important role in promoting sustainable development in China. Subsequent to the seven-year reform, the effectiveness evaluation of the policy in each pilot area and the exploration of the optimization path directly affected the promotion of water resource tax policy and the improvement of water use efficiency. Therefore, the theoretical framework of the water resource tax policy field was constructed to examine the mechanism of the three subsystems of policy scenario, policy orientation, and policy effect; fuzzy-set qualitative comparative analysis (fsQCA) was then used to evaluate and quantitatively compare the policy implementation effect and policy path in each pilot area, with emphasis put on three policy orientations, i.e., the decision and decomposition effect of policy goals, the selection and im plementation effect of policy tools, and the policy supervision and security effect. As shown by the research results: ① the water resource tax reform had effectively improved the efficiency of water resource utilization in the pilot areas; ② three pilot models of water resource tax policy had been extracted, namely the policy goal and tool-driven model centering on a single dimension of the policy field, the implementation-supervision dual drive model emphasizing the supervision and security effect of the policy, and the three-dimensional policy orientation linkage model that focused on the synergistic effect of the policy field; ③ strong heterogeneity existed in water resource tax policy implementation paths and effects in each pilot area. Accordingly, regional heterogeneity could be considered in the process of reform to construct institutionalized, precise, and differentiated reform implementation methods from the perspective of the policy field.水资源税改革对推动中国可持续发展发挥了重要作用。历经七年改革后，各试点地区的政策成效评估与优化路径探索，直接关系到水资源税政策的推广与用水效率提升。为此，本研究构建了水资源税政策场域的理论框架，以考察政策情境、政策导向与政策效应三大子系统的作用机制；随后采用模糊集定性比较分析（fuzzy-set qualitative comparative analysis, fsQCA）方法，对各试点地区的政策实施效果与政策路径进行评估与定量比较，重点聚焦三大政策导向：即政策目标的决策与分解效应、政策工具的选择与落实效应，以及政策监管与保障效应。研究结果显示：① 水资源税改革有效提升了试点地区的水资源利用效率；② 提炼出三类水资源税政策试点模式，分别是以政策场域单一维度为核心的政策目标-工具驱动模式、侧重政策监管与保障效应的实施-监管双驱动模式，以及聚焦政策场域协同效应的三维政策导向联动模式；③ 各试点地区的水资源税政策实施路径与效应存在显著异质性。据此，改革过程中可考虑结合区域异质性，从政策场域视角构建制度化、精准化、差异化的改革实施路径。