徐启渝,王鹏,舒旺,张华,丁明军.土地利用结构与空间格局对袁河水质的影响[J].环境科学学报,2020,40(7):2611-2620
土地利用结构与空间格局对袁河水质的影响
- Investigation of the impacts of land use structure and spatial pattern on water quality in the Yuan River
- 基金项目:国家自然科学基金(No.41201033);江西省重大生态安全问题监控协同创新中心项目(No.JXS-EW-00)
- 徐启渝
- 1. 江西师范大学地理与环境学院, 南昌 330022;2. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室, 南昌 330022
- 王鹏
- 1. 江西师范大学地理与环境学院, 南昌 330022;2. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室, 南昌 330022
- 舒旺
- 1. 江西师范大学地理与环境学院, 南昌 330022;2. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室, 南昌 330022
- 张华
- 1. 江西师范大学地理与环境学院, 南昌 330022;2. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室, 南昌 330022
- 丁明军
- 1. 江西师范大学地理与环境学院, 南昌 330022;2. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室, 南昌 330022
- 摘要:于2018年7月和2019年1月在袁河干流及支流38个采样点采集水样,测定营养盐离子及重金属等14项水质指标.同时,采用Bioenv分析、Mantle检验与方差分解等方法,揭示土地利用结构与空间格局在子流域和缓冲区对水质变化的影响机制,并基于层次分割理论探讨不同土地利用类型的空间格局特征对水质的影响.结果表明:①袁河流域重金属污染不显著,氮、磷营养盐是水体主要污染物,水质变化具有河段差异,上游污染物浓度低于中、下游.②空间格局在在近距离缓冲区(100 m、300 m)对水质变化的解释率最高(63%),土地利用结构在远距离缓冲区(3000 m)和子流域尺度对水质变化的解释率最高(33%),二者交互作用在过渡带(500 m、1000 m)对水质变化的解释率最高(56%).③在近距离缓冲区和过渡带,单一土地利用类型的空间格局对水质变化的解释能力依次为:林地 > 农田 > 建设用地;在远距离缓冲区为:农田≈林地>建设用地;在子流域依次为:农田 > 林地 > 建设用地.其中,林地的连通性特征(ENN_MN指数)、农田的边缘密度特征(ED指数)和建设用地的形状特征(LPI、LSI指数)是影响水质变化的关键特征,占各自空间格局解释率的37.8%、31.2%、53.8%.以上结果表明,土地利用结构与空间格局是驱动袁河水质变化的重要因素,加强1000 m缓冲区尺度土地利用的管理对保护流域水质具有重要意义.
- Abstract:In this study, water samples were taken from 38 sampling sites in the main stream and tributaries of the Yuan River in July 2018 and January 2019, and concentrations of water quality indicators including nutrient ions and heavy metals were measured. Methods such as Bioenv analysis, Mantle test and Variance partitioning were used to reveal the influence mechanism of land use structure and spatial pattern on water quality in buffer zone and sub-watershed, and to explore the impact of spatial pattern characteristics of different land use type on water quality based on Hierarchical partitioning theory. The results showed that:① The heavy metal pollution in the Yuan River Basin was not serious, while nitrogen and phosphorus nutrient salts were the main pollutants in the water body. The concentrations of contaminant in the upstream were lower than those in the middle stream and downstream. ② The interpretation rates of the spatial pattern to water quality was the highest (63%) in the short distance buffer zone (100 m and 300 m buffer zone) scale. The interpretation rates of the land use structure to water quality was the highest (33%) in the long distance buffer zone (3000 m) and sub-watershed scale. The interpretation rates of the interaction between spatial pattern and land use structure to water quality was the highest (56%) in the transition zone (500 m and 1000 m buffer zone). ③ In the near buffer zone and the transition zone, the order of explaining water quality change by spatial pattern of a single land use type were:forest > farmland > construction;In the remote buffer zone that was:farmland ≈ forest >construction;In the sub-basin that was:farmland > forest > construction land. Among them, the connectivity characteristics of forest, the edge density characteristics of farmland and the shape characteristics of construction land were the key characteristics that would affect the change of water quality, accounting for 37.8%, 31.2% and 53.8% of the respective spatial pattern interpretation rates. Land use structure and spatial pattern were the main driving factors of water quality change in the Yuan River, and their interaction played an important role. Strengthening the management of land use in 1000 m buffer zone scale is of great significance to the protection of water environment quality in the basin.