The Relationship Between Multi-scale Spatial Characteristics And Water Quality Response In The Upstream Basin Of Hun River

Hun River is one of the major three rivers flowing into Dahuofang reservoir. As one of the most important drinking water sources of China, the Dahuofang reservoir serves people for drinking water living in nine cities such as Shenyang, Anshan, Funshun etc. Therefore, the water quality of Hun River not only directly affects local people’s life, but also concerns the drinking water security of approximately 22 million people in Liaoning province. This study was committed to illuminate the relationship between river water quality and land-use type and landscape pattern of multi-scale riparian buffers in the upstream basin of Hun River. The results of this study provide scientific basis for exploring the reason and process of regional environmental change and formulating prevention and control programs of watershed aquatic ecological pollution according to local conditions.In this study, Geographic Information System (GIS), Fragststas, CANOCO and SPSS software were successfully used to explore the landscape pattern characteristics in the upstream of Hun River, using the data of remote sensing image, Digital Elevation Model (DEM), water quality monitoring data and aquatic ecological investigation. The landscape index at landscape and class levels was applied to characterize the watershed landscape distribution. Setting five kinds This study focus on the relationship between landscape metrics and water quality at 6 scales of buffer zones with 50m,100m,300m,500m and 800m by Redundancy Analysis (RDA) and correlation analysis. The results are as follows:(1) The predominant land landscape is forest, which has the area of 4003km2.The followed landscape is dry land, whose Percentage of Landscape (PLAND) accounts for 14.35%. The dry land has a high fragmentation degree due to the high percentage of agricultural land affected by human activity. The water body has high connectivity, Largest Patch Index (LPI) of the water body is only less than forest and the number of patch of the water body is the least, which indicate that water in the study area has certain advantages. Paddy fields patch and grass patch are high, having a tendency to fragmentation and the lower natural stability. Residents have high adjacent level and the shape of the patch was relatively regular.(2) The correlation analysis has been employed to determine the relationships between have been employed to determine the relationships in upper watershed of Hun River. The agricultural land and residential land has significant influences on water quality at smaller spatial scale. The woodland and grassland had negative effects on TN, NH4+-N, TP, DO, TDS and BOD5. Dry land and paddy have positive effects on TDS, BOD5, TN, NH4-N and TP. The land use types of upper watershed of Hun River had great influence on water quality within 300 meters range. The influence is gradually weaken when the range is over 300 meters.Therefore, we can achieve the purpose of controlling non-point source pollution through the rational planning of land use types near the river bank.(3) The correlation analysis between water quality and landscape metrics about Hun River upstream basin showed significant heterogeneity of landscape pattern on water quality characteristics at different scales. Patch Density (PD) and LPI had a remarkable impact on water quality within 100 meters range; Number of Patches (NP), Landscape Shape Index (LSI), Shannon’s Diversity Index (SHDI), Contagion Index (CONTAG) and Aggregation Index (AI) had a significant effect on the water quality within 300 meters scale. We recommend to restoring the degraded riparian by ecology project according to local conditions.