How can an ecological compensation threshold be determined? A discriminant model integrating the minimum data approach and the most appropriate land use scenarios.

Ecological compensation has become very common worldwide due to the imbalance in the development of modern society, economy, and the environment and the increased pressure on ecosystem carrying capacity. Nonetheless, the various approaches for quantifying ecological compensation standards differ significantly. Thus, the process for determining a reasonable ecological compensation threshold is important to understand. To ensure the maximization of ecosystem service supply and economic benefit incentives for farmers, this paper constructs a discriminant model of an ecological compensation threshold based on the minimum data approach and the most appropriate land use scenario to define the ecological compensation threshold of the Sloping Land Conversion Program in the upper Yangtze River basin. The results show that with an increase in the compensation price, the proportion of farmers participating in returning farmland to forests and grassland increases, and water conservation increases. However, the discriminant curve first increases to a certain threshold point and then decreases, after which the ecoefficiency rate obtained from the compensation decreases. The ecological compensation thresholds for Chongqing, Sichuan, Yunnan, Guizhou, Hubei, Qinghai, Gansu, Tibet and Shaanxi provinces are 17.74 yuan/m, 13.79 yuan/m, 19.1 yuan/m, 17.79 yuan/m, 15.28 yuan/m, 45.14 yuan/m, 17.23 yuan/m, 25.2 yuan/m and 22.36 yuan/m, respectively. This research examines ecological compensation standards in different watersheds throughout the world and discusses the relationship between ecological compensation and water conservation. The discriminant model of the ecological compensation threshold can provide a new reference for the implementation and management of ecological compensation policies.