赤水河流域生态状况与变化特征综合评估

ANALYSIS OF ECOLOGICAL PROTECTION SITUATION AND ITS VARIATION CHARACTERISTICS OF THE CHISHUI RIVER BASIN

从区域生态系统综合评估视角,对赤水河流域2001—2020年生态格局、质量和功能现状和变化特征开展定量评估,耦合社会经济指标,识别流域生态保护特点和空间分异规律。结果表明:赤水河流域上、中、下游各子流域在各评估指标中均表现出明显的梯度变化特征,流域下游生态本底最好,中游其次,上游最差。具体来看,流域下游生态格局和功能较为稳定,并且呈稳中向好的变化特征,如位于下游的大同河子流域以森林生态系统为主,生态质量指数为74.22,是整个赤水河流域中最高的区域。从生态保护与经济社会发展的协调性来看,下游体现出生态保护和民生改善“双赢”的特点;流域中游和上游生态格局和功能指标受干扰最大,部分子流域明显变差,如上游的倒流河河口至小河渡口子流域最为典型,单位面积水源涵养量年均降幅达到1.21万m^(3)/km^(2),流域上游人均GDP增速最慢,仅为0.08万元/a,仅为流域中游人均GDP增速的1.9%,需要在加大生态保护力度的同时探索经济社会发展的新增长模式。

From the perspective of comprehensive assessment of a regional ecosystem,this study carried out a quantitative assessment on the current situation and change characteristics of ecological pattern,quality and function of the Chishui River Basin from 2001 to 2020,and coupled social and economic indicators to identify the characteristics of ecological protection and spatial differentiation of the basin.The results showed that the upper,middle and lower sub-basins of the Chishui River Basin had obvious gradient change characteristics in each evaluation index.The ecological background of the lower reaches of the basin was the best,followed by the middle reaches and then the lower reaches.Specifically,the ecological pattern and functions in the lower reaches of the basin were relatively stable,and showed steady and positive changes.For example,the Datong River Sub-basin located in the lower reaches was dominated by forest ecosystems,with an ecological quality index of 74.22,which was the highest in the whole Chishui River Basin.From the perspective of the coordination between ecological protection and economic and social development,the downstream reflected Win-Win characteristics of ecological protection and people’s livelihood improvement;the ecological pattern and functional indicators in the middle and upper reaches of the basin were most disturbed,and some sub-basins were significantly worse.For example,the sub-basin from the Daoliu River Estuary to Xiaohedukou in the upper reaches is the most typical,with an average annual decrease in water conservation per unit area of 12100 m^(3)/km^(2);the growth rate of per capita GDP in the upper reaches of the basin was the slowest,only 800 yuan/a,which was 1.9% of the growth rate of per capita GDP in the middle reaches.It was necessary to strengthen ecological protection and explore a new growth mode of economic and social development.