基于SWAT模型的浑河中上游水源涵养服务价值评估

浑河中上游流域的森林覆盖率高达68%,是辽宁省饮用水的重要水源保护地。本研究基于SWAT模型和影子工程法,评估2000—2019年浑河中上游流域的水源涵养量及其服务价值,并分析其时空变化的原因,以期为流域内生态补偿和生态恢复提供依据。结果表明:2000—2019年浑河中上游水源涵养量及其价值量呈先增加后减少趋势;年均水源涵养总量和水源涵养服务价值分别为24.6亿m³和150.4亿元;研究区水源涵养量存在明显的空间差异,高值区主要分布在清原县和新宾县,低值区集中于沈阳市辖区;不同生态系统的水源涵养服务价值差异较大,森林的单位面积水源涵养量远高于草地、农田和城市。

Evaluation of the value of water retention service in the middle and upper reaches of Hunhe River based on SWAT Model

The upper and middle reaches of the Hunhe River, with forest coverage rate up to 68%, is an important water source protection area in Liaoning Province. Based on the SWAT model and shadow engineering method, we aimed to estimate the function and service value of water retention in the upper and middle Hunhe River basin from 2000 to 2019, to analyze the spatial heterogeneity, and to provide a scientific basis for the ecological compensation and ecological restoration of the region. Our results showed that the function and service value of water retention in the upper and middle reaches of the Hunhe increased first, and then decreased from 2000 to 2019. The mean annual amount and service value of water retention were 2.46 billion m³ and 15.04 billion yuan, respectively. The spatial distribution of water conservation service functions in the study area was uneven. The areas of high water retention service value were mainly distributed in Qingyuan County and Xinbin County, while the low-value areas were located in municipal districts of Shenyang City. The value of water retention services was obviously different among the ecosystems, with water retention capacity per unit area of forests being much higher than that of grassland, farmland, and cities.