水源涵养型国家重点生态功能区生态系统服务功能评估

为评估“十二五”以来国家重点生态功能区转移支付政策的阶段性实施效果，以水源涵养类型国家重点生态功能区为对象，基于水量平衡法，利用2011年和2019年土地覆被数据，并结合气象数据，分析了水源涵养型国家重点生态功能区2011年和2019年水源涵养功能、生态系统面积、生态系统质量状况及其变化情况。研究结果表明，自2011年转移支付政策实施以来：1)全国水源涵养型重点生态功能区内的水源涵养能力呈现从西北部到东南部逐渐增加的空间分布趋势，2019年全国水源涵养型重点生态功能区水源涵养能力较2011年显著增加。2)全国水源涵养型重点生态功能区森林面积有所增加，湿地得到有效恢复。3)全国水源涵养重点生态功能区内生态系统质量提高，平均植被覆盖度有所增加，呈现东北部及中南部高，西北部低的分布趋势。总体来看，转移支付政策的实施对全国水源涵养重点生态功能区森林、草地生态系统水源涵养功能的提升发挥了积极作用，基本上达到了转移支付政策预期的阶段性目标。

Assessment of ecosystem services in the national key ecological function areas for water conservation

The transfer payment policy in national key ecological functional areas has been implemented since the "12th Five-Year Plan", but the effect of this policy on the ecosystem, especially in water conservation type national key ecological function areas, is far from being clearly understood. The objective of this study is to evaluate the phased implementation effect of transfer payment policy in the national key ecological function areas. In this research, water balance method was employed to analyze the water conservation function and its changes in 2011 and 2019. The area and the quality of the ecosystem in 2011 and 2019 were evaluated using land-cover data and meteorological data. The results showed that since the implementation of the transfer payment policy in 2011:(1) the capacity of water conservation in the national key ecological function areas of water conservation presents a spatial distribution trend that gradually increases from the northwest to the southeast. In 2019, the capacity of water conservation in the national key ecological function areas of water conservation increased significantly compared with 2011. (2) The area of forests in key ecological function areas for water conservation has increased, and wetlands has effectively restored in the national key ecological function areas of water conservation from 2011 to 2019. (3) The quality of the ecosystem in the water conservation type national key ecological function areas has improved, and the average vegetation coverage has increased, showing a trend of high distribution in the northeast and south central and low in the northwest from 2011 to 2019. Overall, the implementation of the transfer payment policies, such as natural forest protection, returning farmland to forest, returning grazing land to grass and other projects, have played a positive role in improving the water conservation function of forests and grassland ecosystems in the national key ecological function areas of water conservation. However, we should pay enough attention to a small number of water conservation type national key ecological function areas where water conservation functions have declined, and strengthen ecological protection to avoid the degradation of ecosystem services. Therefore, it is possible to control the disorderly expansion of cities, reduce the area of bare land, increase the area of forest and grassland wetland, and improve the forest structure, there by improve the water conservation function and reflect the benefits of the use of transfer payment funds. For areas where the ecological environment has significantly improved, the central government should give appropriate rewards.