极端干旱条件下河道生态基流间接价值计算

Study on River Ecological Base Flow Value in Extremely Dry Conditions

根据水生态系统提供的服务机制、类型和效用,水生态系统的服务功能可分为提供产品功能的直接使用价值和具有生命支持系统的间接使用价值两大类,河道生态基流的间接服务功能又包括水生态调节功能,水生态文化功能和水生态支持功能三类。生态基流保障的关键期为枯水期,极端干旱条件下生态基流同样蕴涵着不容忽视的价值,根据河道生态基流的各项服务功能及其影响因素,各项价值采用资源环境经济学的方法来进行估算。以渭河宝鸡段为例,以2015年为评价基准年份,对极端干旱年份下生态基流的间接价值进行了计算。结果表明,渭河宝鸡段2015年生态基流总价值为38 301.9万元/a,其中调节功能价值为25 581.6万元/a;支持功能价值为220.3万元/a;文化功能价值为12 500万元/a。开展本次研究,为缺水地区生态基流长效保障与生态补偿机制的建立等提供理论支撑与科学依据。

According to function and effectiveness, two kinds of aquatic ecosystem services, product supply and environmental and life support services, are identified. Water ecosystem services are divided into three groups, including regulating, supporting and cultural services. Dry season is the critical period of ecological base flow in water shortage areas. Ecological base flow value is enormous in extremely dry conditions. Ecological base flow value can be estimated by means of resource and environment economics according to their service function and influential factor. The results showed that the total value of water ecosystem services of Baoji section in Wet river in the year of 2015 was 3.83×10^8 Yuan, in which regulating function was the most valued water ecosystem service function, 2.55 × 10^8 Yuan; the value of supporting and cultural function was 0.02×10^8 Yuan and 1.25 × 10^8 yuan, respectively. This study can provide theoretical support and scientific basis for the long-term ecological base flow protection and the establishment of ecological compensation mechanism in water shortage areas.