Quantifying inter-regional payments for watershed services on the basis of green ecological spillover value in the Yellow River Basin, China

The inter-regional payments for watershed services (PWS) is an important policy to promote environmental cooperation in the river basin management. However, existing PWS in China may overestimate the value of watershed-related ecosystem services (WES) and induce a mismatch between ecological benefits and costs of stakeholders. A equitable framework of inter-regional PWS standards is necessary for the policymakers, especially in Yellow River Basin. For this reason, the focus of current article was emphasized on green ecological spillover value through multi-regional input-output model deducting suppliers' own watershed services consumption, then explored the influencing factors of watershed-related ecological benefits, ecological profit or loss and spatial spillover conditions within Yellow River Basin, finally designed inter-regional PWS transfer standards. The estimated results revealed that watershed-related ecological benefits within Yellow River Basin had obvious heterogeneous characteristics and spatial spillover. The implementation of economic financial power, awareness of water resources ecological functions, and inter-regional PWS policies could significantly improve watershed-related ecological benefits, and the increase in water resources protection routine power led to the loss of watershed-related ecological benefits. Based on the green ecological spillover value, we comprehensively considered factors such as water resources protection routine power, economic financial power, and awareness of water resources ecological functions to design an inter-regional PWS transfer program, which was reasonable and feasible in theory and practice. For regional ecological and environmental cooperation, it is essential to strengthen spatial spillover and improve the level of inter-regional PWS, which may pave the way for other river basins or countries.