秦岭北麓及周边生态系统水质净化功能评估

Water Purification Function Evaluation of the Northern Slop of Qinling Mountains and Its Surrounding Ecological System

该文以秦岭北麓周边生态系统为研究对象,采用InVEST模型,从流域及子流域尺度评估秦岭北麓周边生态系统2000年和2010年的水质净化功能,并借助研究区的生态环境信息,对秦岭北麓水质净化功能的影响因素做出分析探究,结果表明:(1)2000年、2010年秦岭北麓N素输出量分别为4 997.17、5 003.69 t,P素输出量分别为263.32、256.98 t。黑河和浐河流域的单位面积N、P输出量最小,水质净化能力较强;灞河和潼河流域的单位面积N、P输出量最大,水质净化能力相对较弱。(2)秦岭北麓的N、P输出保持量与农田覆盖率成正相关关系,与草地、森林及灌丛的覆盖率成负相关关系。各植被类型中,旱地、落叶阔叶林和落叶阔叶灌木林的单位面积N、P输出量较大。从土壤类型来看,沼泽土的单位面积N、P输出量最高。

The northern Qinling Mountains and its surrounding ecological system was taken as the research object, and the water conservation and water purification ability and its spatial pattern heterogeneity in 2000 and 2010 from the scale of the watershed and sub-watershed were evaluated by using the InVEST model. Based on the ecological environment information of the study area, the sensitivity factors of water conservation and water purification function were analyzed and explored. The results showed that in 2000 and 2010, the outputs of N in northern Qinling was 4 997.17 t and 5 003.69 t, the outputs of P was 263.32 t and 256.98 t. Hei River basin and Chan River basin has the minimum amount of N, P output in per unit area and strong quality purification capacity. Ba River basin and Tong River basin has the largest amount of N, P output in per unit, and the water purification capacity is relatively weak. In northern Qinling, N, P outputs and retentions keep positively correlated relationship with farmland coverage, and keep negatively correlation relationship with grassland, forest and shrub coverage. Among various vegetation types of northern Qinling, farmland, deciduous broad-leaved forest and deciduous broadleaf shrub has larger per unit N, P output. In terms of soil properties, bog arable soil has the highest N,P outputs in per unit.