浑太河流域多尺度土地利用/景观格局与水质响应关系初步分析

选取浑太河流域为研究对象,采用GIS、相关性分析、多元线性回归分析等多种数理统计分析技术,从子流域和河岸缓冲区尺度分析了土地利用、景观格局对河流水质的影响。结果表明:农业用地面积比例在子流域和1000m河岸缓冲区尺度与NH4+-N、TN、BOD5和COND呈正相关;林地用地面积比例在子流域尺度和河岸缓冲区尺度均与CODMn呈负相关,在300m、400m、1000m河岸缓冲区尺度与TN呈负相关,在1000m河岸缓冲区尺度与COND呈负相关,在子流域与1000m河岸缓冲区尺度与NO3-呈正相关;草地在子流域尺度与NH4+-N、TN、TP、Chl、CODMn呈正相关;建设用地面积比例在子流域尺度与BOD5、COND、TN呈正相关。CONTAG在河岸带缓冲区尺度与COND、TN呈正相关,在子流域和河岸缓冲区尺度与均CODMn均呈正相关,在河岸缓冲区尺度与NO3-呈负相关;PD在子流域尺度上与TN呈正相关,ED在子流域尺度上与NO3-呈正相关,与NH4+呈负相关;SHDI在子流域与河岸缓冲区尺度与NO3-均呈负相关。相对于河岸缓冲区尺度,土地利用类型在子流域尺度上对水质的影响更为显著,表现在调整判定系数Adjusted R2更大。而景观格局指数中对水质影响最大的是CONTAG,相对于子流域尺度,CONTAG在缓冲区尺度上影响更为显著。

A Preliminary Study on the Relationship Between Multi-scale Land Use & Landscape and River Water Quality Response in the Huntai Watershed

Geographic Information System(GIS),Correlation Analysis,and Multiple Linear Regression were integrated to link land use & landscape pattern and water quality at the sub-watershed and buffer zone scale in the Huntai River Watershed.Results showed that the percentage of cropland area was positively correlated with NH+4-N,TN,BOD5 and COND in the sub-watershed and 1000 m buffer zone;the percentage of woodland area was negatively correlated with CODMn in the sub-watershed and all buffer zones,and was negatively correlated with TN in 300 m,400 m and 1000 m buffer zones,and was negatively correlated with COND in 1000 m buffer zone,and was positively correlated with NO-3 in the sub-watershed and 1000 m buffer zone;the percentage of built-up area was positively correlated with BOD5,COND and TN and the percentage of grassland area was positively correlated with NH+4-N,TN,TP,Chl,CODMn in the sub-watershed.CONTAG was positively correlated with COND and TN in all buffer zones and was positively correlated with CODMn in the sub-watershed and buffer zones,was negatively correlated with NO-3 in the buffer zones;PD was positively correlated with TN in the sub-watershed;ED was positively correlated with NO-3 and was negatively correlated with NH+4-N in the sub-watershed;SHDI was negatively correlated with NO-3 in the sub-watershed and buffer zones.Compared to buffer zone area,the parameters for water quality in the sub-watershed area have more significant correlations with the percentage of land use-type area,because most water quality parameters for the sub-watershed can be better explained with greater adjusted coefficients of determination(Adjusted R2),parameters for water quality.CONTAG has the most important influence in all landscape metrics.The parameters for water quality in buffer zone area have more significant correlations with CONTAG.