生态补水后永定河北京山区段河流生境质量评价

河流生境作为河流生态系统的重要组成部分,准确评估河流生境质量可为河流生态保护与恢复管理提供重要的依据。结合永定河北京山区段生态环境特点,采用层次分析法构建了包括河道生境、河岸生境、滨岸带生境3个方面共12项指标的河流生境质量评价体系,分析生态补水后永定河北京山区段河流生境现状及其空间分布。研究结果表明:北京山区段河流生境质量总体偏好,30个样点中,处于极好、好、一般等级的样点数分别为8个、11个、11个,无差和极差等级样点。生境质量总体状况在空间上表现为官厅至珠窝水库河段>珠窝坝下至落坡岭水库河段>落坡岭坝下至三家店水库河段,各个河段的河道生境、河岸生境、滨岸带生境均存在显著性差异;人类活动、土地利用方式、河岸植被结构、河岸护坡类型等对生境质量及水质具有较大的影响。通过对河流生境质量评价不仅能够较好地反映生态补水后北京山区段河流生境质量现状,也可为进一步的河流生态恢复与管理提供科学依据。

Habitat Quality Evaluation of Yongding River in Beijing Mountain Section after Ecological Rehydration

The assessment of river habitat quality can provide an important basis for river ecological protection and restoration management.Combined with local ecology and environment,a river habitat quality assessment system is established by using hierarchical analysis method,which includes three habitats(channel habitat,bank habitat and riparian habitat).The river habitat quality of Beijing mountain section of the Yongding River is also assessed.The results show that the river habitat quality of the 30 sampling plots are good on the whole,with 8 sampling plots classified as“excellent”,11 as“good”,and 11 as“moderate”.For different river reaches,the situation of overall river habitat quality and three habitats consistently show significant differences,ranking that Guanting to Zhuwo Reservoir>Zhuwo Dam to Luopoling Reservoir>Luopoling Reservoir to Sanjiadian Reservoir.Human activities,land use patterns,riparian vegetation structure and bank slope type have a significant influence on river habitat quality and water quality.This study can not only reflect the status of river habitat quality in Beijing mountain section after ecological water supply,but also provide a scientific basis for river ecological restoration and management.