长江流域水源涵养服务价值及其空间转移评估

Evaluation of Water Source Conservation Service Value and Its Spatial Transfer in Yangtze River Basin

水源涵养服务价值在不同区域之间的转移是流域上下游之间进行横向生态补偿需要考虑的关键内容。然而,水源涵养服务价值的转移依赖于流域的水文循环路径和河流的水量输送。现有的生态系统服务价值转移量评估方法缺乏对水源涵养服务转移中水文特征的描述,评估结果的合理性有待加强。针对此问题,从转移方向和转移路径2个方面改进断裂点-场强模型,通过引入河流方向系数判断流域上下游以及干支流地区之间的水力联系,在水源涵养服务转移评估中考虑河流的水文特征,并在长江流域应用,提高评估结果的合理性与可用性。结果表明,2020年长江流域水源涵养量为11 538.45亿m3,水源涵养服务的价值量为11 953.83亿元。相比现有模型的评估结果,研究改进的断裂点-场强模型突出了水源涵养服务价值从流域上游向下游转移的特征、增加了转移强度和范围。长江流域水源涵养服务价值的转出量由大到小依次为:四川>江西>湖南>贵州>湖北>安徽>重庆>云南>浙江>青海>陕西>广西>西藏>河南;各省份水源涵养服务价值的转入量由大到小依次为:云南>安徽>湖北>重庆>江苏>湖南>四川>上海>西藏。

The transfer of water source conservation service value between different regions is the key content to be considered in the horizontal ecological compensation between the upstream and downstream of river basin.This transfer is dependent upon the basin' s hydrological cycle path and river water transport.However,the current method for evaluating the transfer of water source conservation service value lacks an account of hydrological characteristics,thus requiring an enhancement of the rationality of evaluation results.Addressing this issue,the present study enhances the fracture point-field intensity model from two perspectives:transfer direction and transfer path.Firstly,the introduction of the river direction coefficient aids in assessing the hydraulic connection between the basin's upstream and downstream,as well as its main and tributary regions.Secondly,the assessment of water source conservation service transfer takes into account the hydrological characteristics of rivers,with particular application to the Yangtze River Basin(YRB),thereby improving the rationality and applicability of assessment outcomes.The findings reveal that the water source conservation capacity of the YRB in 2020 reached 1 153.85 billion m3,with the associated value of water source conservation service amounting to 1 195.38 billion yuan.In contrast to the evaluation results obtained from existing models,the present enhanced fracture point-field intensity model underscores the transfer of water source conservation service value from upstream to downstream,and amplifies the transfer intensity and range.Within the YRB,the water source conservation service value transferred from Sichuan ranks the top,followed by Jiangxi,Hunan,Guizhou,Hubei,Anhui,Chongqing,Yunnan,Zhejiang,Qinghai,Shaanxi,Guangxi,Xizang,and Henan in descending order;the service value received by Yunnan is the largest,followed by Anhui,Hubei,Chongqing,Jiangsu,Hunan,Sichuan,Shanghai,and Xizang in descending order.