Measuring the cross-border spillover effects and telecoupling processes of ecosystem services in Western China

Ecosystem services provide the basic elements for global economic development. In the context of the deepening global integration process, countries and regions are increasingly connected, resulting in a series of cross-country, cross-regional, multi-scale socio-economic-environmental impacts, these new situations and changes require a multi-site, two-way, and cross-temporal and spatial scale comprehensive study of "the relationship between ecosystem services and humans". Based on this, we apply a telecoupling synthesis framework to explore the socio-economic and eco-environmental interactions of ecosystem service spillover effects. Results show that (1) the spillover effect of ecosystem services in western China is significant. More than 66% of ecosystem services spillover to eastern China provinces, and more than 40% of ecosystem services spillover to countries in Southeast Asia, South Asia, and Central Asia, resulting in a total of 679 million people benefiting from the spillover effect. (2) There are also multiple telecoupling processes between the ecosystem service spillovers in the ecologically fragile areas in western China and the rest of the world. In combination with the scenario simulation of the InVEST model, the services such as water supply, soil retention, flood mitigation, and food supply have significant impacts on sustainable development and human well-being in Asia and even the world. (3) The positive feedback effect of telecoupling is critical to the protection of the ecological environment as well as the improvement of people's livelihood and well-being in Western China's ecologically fragile areas. Therefore, we propose strengthening ecological compensation cooperation between local governments and implementing compensatory transfer payments between upstream and downstream. Simultaneously, international cooperation must be strengthened, and an ecological compensation transfer mechanism with beneficiary countries must be established, while the cross-regional flow of ecosystem services must be maintained. This study provides an example for the "ecosystem services and human relations" in multiple places, two directions and across time and space scales, and also practical reference significance for China implementation of projects such as the "the Belt and Road" initiative and transnational and cross regional resource allocation.