Mapping regional differences in payment for ecosystem service policies to inform integrated management: Case study of the Yangtze River Economic Belt.

State and local governments consider payment for ecosystem services (PES) a valuable tool for watershed protection. However, regional differences in PES policies, which significantly influence province-scale cooperation, have been seldom documented. The interrelationships among these policies directly affect overall PES development in the Yangtze River Economic Belt (YREB). Textual analysis was used to categorize the content of PES policies in 11 provinces from 2004 to 2018. Then, we assessed these PES policies with four indicators (i.e., policy intensity, interdepartmental coordination, diversity, and duration). Finally, we analyzed the impact factors of these regional differences. The results showed that the number of PES policies increased yearly, reaching a peak in 2017. Provinces in the upper reaches had the highest policy-intensity score (7.38), followed by downstream provinces (6.39) and provinces in the middle reaches (4.52). Regarding interdepartmental coordination, the downstream areas exhibited the most interdepartment interaction (27.92%), followed by the upstream areas (20.76%) and the middle areas (19.18%). Diversity in the middle reaches was the highest (scored 4.3) while the upstream area exhibited the lowest diversity value (3.25). Downstream provinces issued PES policies the earliest, with a duration 5.52 years, followed by the upstream provinces (4.68) and middle provinces (4.28). Policy intensity was significantly correlated with fixed-asset investment, solid-waste generation, and population. The results suggest that PES in the YREB needs to be strengthened by enhancing policy consistency. In this regard, identifying regional differences in PES policies can help improve the coordination of PES policies for the whole YREB.