Emergy Analysis and Ecological Spillover as Tools to Quantify Ecological Compensation in Xuchang City, Qingyi River Basin, China

Abstract

As an effective means to coordinate cost–benefit allocation of ecological protection between upstream and downstream cities, ecological compensation is often used to improve collaborative basin-wide freshwater resources management. Yet, due to the complex relationships between upstream and downstream ecosystem services, calculating eco-compensation is not an easy task. We used ecological spillover (the amount of local ecosystem services not used in the region and thus flows to downstream areas) and emergy analysis to determine the amount of eco-compensation that the city of Xuchang should pay to the upstream city of Xinzheng (Qingyi River Basin, China) from 2010 to 2014. Eco-compensation was determined by deducting the emergy of the local, self-supplied ecosystem services of Xuchang City, calculated using an ecological-water-footprint-based analysis, from the emergy of the total ecosystem services used in Xuchang, and monetized accordingly. The results showed that the self-supplied ecosystem services decreased from 2010 to 2014 and, thus, Xuchang relied more on the ecological spillover services flowing from Xinzheng. As a result, eco-compensation increased from 990 million Chinese Yuan (¥) in 2010 to ¥509 billion in 2014, mostly due to increased demands for water purification and reduced precipitation around Xuchang. This method can be further enhanced by introducing larger datasets and can be replicated elsewhere to accurately determine ecological compensation, ensuring basin-wide collaboration towards the sustainable management of freshwater resources.