河溪生境因子对土地利用变化的响应研究

为明确河溪生境因子对河岸土地利用方式变化的响应程度,在北京市郊区选取3条典型河溪中的50个河段,进行不同河岸土地利用方式下生境指标的差异性检验和主成分分析.经过因子旋转,最终确定4个综合生境因子来反映不同河岸土地利用方式对河溪生态系统的影响,并通过PLOT过程在二维平面上用散点图表示.结果表明,研究区旅游用地对河溪中底栖动物多样性和磷酸盐浓度有突出影响；公路也能促进底栖动物多样性的增加以及磷酸盐浓度的增大,但影响不及旅游用地；居民用地对氨氮浓度的影响最大,农地对浮游植物多样性及pH值和溶解氧含量影响最大.维持合理的河岸土地利用方式,是促进北京郊区河溪生态系统自我修复的重要途径.

Responses of Stream Habitat Factors to Land Use Change

To clarify the responses of stream habitat factors to riparian land use change,50reaches of 3typical streams in the suburb of Beijing City are selected for the discrepancy test and principal component analysisof habitat indicators under different riparian land uses.By factorial rotation,four integrated indicators areconfirmed to reflect the impacts of different riparian land uses on stream ecosystem,which are shown inplots.Results show that the land for tourism has greater effect on benthic macroinvertebrates species and theconcentration of phosphorus in stream than the land for transportation;the land for inhabitancy increases theconcentration of nitrogen in stream;and farmland affects phytoplankton species,pH value and the concentration of dissolved oxygen.Maintaining rational land use is a basic approach to stream ecological restoration inthe suburb of Beijing City.