鲁东山区流域景观格局与面源污染关联关系

基于实地监测和3S技术,以鲁东低山丘陵地区栖霞市为研究区,采用Spearman相关、非约束性PCA、对应典范分析（CCA）等方法,研究不同流域尺度下景观格局与面源污染的关联关系。结果表明：（1）研究区景观格局空间分异明显,在特征尺度下农用地和建设用地斑块较为破碎,林地、园地斑块聚集性强。（2）研究区河流面源污染物主要以TN为主,EC、COD污染次之,主河道出水口为污染较为严重的区域。（3）景观格局对水质的影响丰水期要大于平水期,TN和EC对土地利用类型面积比例和景观格局指数的变化最为敏感。（4）平水期河岸带尺度下景观格局对TN影响最大的为斑块密度,EC受景观边缘密度影响最大,小流域尺度TN受景观蔓延度影响最大,COD与景观多样性关系密切;丰水期河岸带尺度景观多样性对TN影响最大,EC受斑块聚合度影响最大,小流域尺度影响TN最大的因素与平水期一致,EC与景观蔓延度关系密切。（5）小流域景观类型水平下,TN主要受林地斑块密度影响,TP与耕地散布与并列指数关系密切;丰水期TN受林地散布与并列指数影响显著,TP对林地平均分维数变化敏感,EC受草地聚集性影响最大。本文分析了研究区景观格局与面源污染空间分布特征,探讨了两者在不同尺度下的相关性,可为栖霞市水土资源可持续利用提供科学依据。

Relationship of landscape pattern and non-point source pollution in mountainous area of Eastern Shandong province

Based on field monitoring and 3S technology, Qixia city in the low hilly area of Eastern Shandong province was taken as the research area. Pearson correlation, unconstrained PCA and corresponding canonical analysis (CCA) were used to study the coupling between landscape pattern and non-point source pollution at different watershed scales. The results show that: (1) The spatial variation of landscape pattern is obvious; the patches of agricultural land and construction land are relatively fragmented at the characteristic scale; and the patches of other types of land are highly aggregated. (2) The river surface source pollutants in the study area are mainly TN-based, and the main river outlet is the more polluted area. (3) The influence of landscape pattern on water quality during the wet period is greater than that of the normal water period, and TN and EC are most sensitive to the change of land use type area ratio and landscape pattern index. At different scales, water quality affected by landscape pattern and land use type is different. (4) In normal period at riverside scale, landscape that has the greatest impact on TN is the patch density, and EC is most affected by landscape edge density. At small basin scale TN is greatly affected by landscape spread, and COD is closely related to landscape diversity. The diversity of landscape on the scale of the riverbank during the wet period has the greatest influence on TN, the EC is greatly affected by the polymerization of the plaques, and the biggest factors affecting TN on the small basin scale are consistent with the flat water period, and EC is closely related to landscape spread. (5) At small basin landscape, TN is mainly affected by the density of forest land patch, TP and cultivated land dispersion are closely related to the parallel index, the abundance of water TN is significantly influenced by the forest land dispersion and juxtaposition index, TP is sensitive to the change of the average dimensionality of forest land, and EC is most influenced by grassland aggregation. Basically, the study clarified the spatial distribution characteristics of landscape pattern and non-point source pollution in the study area, and discussed the correlation between them at different scales, which provided a scientific basis for sustainable utilization of water and land resources in Qixia city.