辽河流域河流栖息地评价指标与评价方法研究

建立了由底质、栖息地复杂性、速度-深度结合特性、堤岸稳定性、河道变化、河水水量状况、植被多样性、水质状况、人类活动强度和河岸土地利用类型所构成的河流栖息地评价指标体系,确定了各指标的等级划分以及栖息地综合指数的计算方法.结合2005年辽河流域河流生态调查结果,对流域内所调查的28个河段的栖息地质量状况进行了具体评价,并进一步分析了河道栖息地综合指数与河流理化因子、底栖生物以及小流域土地利用状况的相关关系.结果表明:①辽河流域28个河段的栖息地质量状况差异显著,其中10个河段达到了较好等级以上,6个仅为中等水平,12个河段为较差等级以下;②栖息地质量与理化因子、底栖生物指标具有显著相关性,表明栖息地质量是影响水质与生物状况的重要因素;③小流域的人类未利用土地比例与栖息地质量显著相关,表明小流域土地利用程度对栖息地环境质量影响较大,是恢复与保护河流栖息地质量的重要条件.

Study of indicators and methods for river habitat assessment of Liao River Basin

A comprehensive river habitat assessment index and calculation method are developed, which integrated the following indicators: substrate, habitat complexity, velocity-depth combination, bank stability, channel alteration, stream flow conditions, vegetation diversity, water quality conditions, intensity of human activities and riverside land use. The grade of indicators and integrated assessment methods of habitat index are proposed accordingly. Incorporate with the Liao Basin ecological survey results, 28 reaches were chosen as the detailed habitat quality assessment in the Liao River basin. The correlation among the comprehensive habitat quality index, the physical and chemical parameters, the benthic organism and the local watershed land use were further evaluated to validate the effectiveness of the assessment method. The results indicate that: (1) There are significant differences in habitat quality among reaches 10 reaches achieved preferable level or better and 12 were poor or worth and 6 were fair; (2) There is significant relationship between habitat quality and physiochemical parameters as well as benthic organisms, which shows that habitat quality is a major factor impacting the water quality and biota conditions; (3) There is significant relationship between natural vegetation proportion of watershed and habitat quality, which shows that land use pattern of watershed has a strong impact on habitat environment.