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利用GIS技术进行河流等级结构划分,研究了三峡库区东河流域河流的等级体系。将整个东河流域河溪分为6级,并在此基础上研究了不同等级河溪与海拔高程和坡度的关系。研究发现,河溪在由低等级向高等级变化时,其空间分布范围逐渐由坡度大、海拔高向坡度小、低海拔的平缓地带过渡;低等级溪流周围植被生长状况好于高等级溪流周围植被。东河1、2级河流生态结构的完整性主要受自然干扰影响。3、4级河流水体落差大,水能丰富,河流主要受小水电影响;建议充分考虑河流生态需水,维护河流生境的连通性,保证水坝下游河段的河流生态健康。5、6级河流沿岸人为活动强度较大,水质较差;建议对河岸植被进行改造和重建,提高河岸植被的多样性和群落结构层次,减缓面源污染对河流健康的影响。对受三峡水库水位的波动影响的河段,建议实施生态恢复工程,改善生态环境质量。
Using GIS technology to classify the river hierarchy, the paper studies the hierarchy of rivers in the Donghe River Basin in the Three Gorges Reservoir Area. The whole Donghe river basin is divided into 6 levels, and on this basis, the relationship between different grades of river and elevation and slope is studied. The study found that when the river changed from low level to high level, the spatial distribution gradually changed from large slope, low elevation to gentle slope and low altitude. The growth of vegetation around low grade stream was better than that of high grade stream vegetation. The integrity of the ecological structure of rivers in the first and second class of the East River is mainly affected by natural disturbances. Grade 3 and 4 rivers have a large gap between water bodies and abundant water. The rivers are mainly affected by small hydropower. It is suggested that ecological water demand should be fully taken into account and the connectivity of river habitats should be maintained so as to ensure the ecological health of rivers downstream of the dam. It is suggested that the river bank vegetation should be rebuilt and rebuilt so as to improve the diversity of river bank vegetation and the level of community structure so as to mitigate the impact of non-point source pollution on river health. For the sections affected by the fluctuation of the water level of the Three Gorges Reservoir, it is suggested that ecological restoration projects be implemented to improve the ecological environment quality.