Wang Yonggui, Song Zhen, Bai Hui, Tong Hongjin, Chen Yan, Wei Yao, Wang Xiaoyu, Yang Shuihua
Hubei Key Laboratory of Regional Ecology and Environmental Change, School of Geography and Information Engineering, China University of Geosciences, Wuhan, 430074, China.
United Center for Eco-Environment in Yangtze River Economic Belt, Chinese Academy of Environmental Planning, Beijing, 100012, China.
Environ Sci Pollut Res Int. 2023 Apr;30(16):48002-48020. doi: 10.1007/s11356-023-25284-2. Epub 2023 Feb 7.
Assessing the scale effects of land use on water quality is of great significance for effectively controlling nonpoint source (NPS) pollution in river basins. In this study, redundancy analysis (RDA) and stepwise multiple linear regression (SMLR) analysis were applied to assess the effects of land use on water quality across multiscales in the Tuojiang River Basin. All monitoring sections were classified into three groups according to the characteristics of land use and cluster analysis of water quality. Results showed that the improvement in water quality of rivers in the Tuojiang River Basin lies in the emphasis and protection of the small-scale scope. Concomitantly, the linkages between individual water quality parameter and land use were highly dependent on spatial scales and regional basis. For the upstream group A, urban land is the main source of COD and TN pollution, while industrial and rural residential land contributed the most to TP pollution. Water body exhibits favorable effects on ammonia nitrogen due to its absorption and degradation, together with the growth of phytoplankton within it. For group B in the middle-lower reaches, controlling the input of organic fertilizers in paddy field will effectively alleviate COD pollution. Increasing the proportion of grassland near the riparian zone can have a positive effect on TN and TP pollution. It should continue to strengthen the strict supervision of NH-N concentration in wastewater discharge from industrial enterprises. Our results can provide important information for land use planning and making multiple scale measures for water quality conservation.
评估土地利用对水质的尺度效应对于有效控制流域非点源（NPS）污染具有重要意义。本研究应用冗余分析（RDA）和逐步多元线性回归（SMLR）分析来评估土地利用对沱江流域多尺度水质的影响。根据土地利用特征和水质聚类分析，将所有监测断面分为三组。结果表明，沱江流域河流的水质改善在于对小尺度范围的重视和保护。同时，单个水质参数与土地利用之间的联系高度依赖于空间尺度和区域基础。对于上游A组，城市土地是化学需氧量（COD）和总氮（TN）污染的主要来源，而工业和农村居民用地对总磷（TP）污染的贡献最大。水体由于其吸收和降解以及其中浮游植物的生长，对氨氮具有良好的影响。对于中下游的B组，控制稻田中有机肥料的投入将有效减轻COD污染。增加河岸带附近草地的比例对TN和TP污染有积极影响。应继续加强对工业企业废水排放中氨氮浓度的严格监管。我们的结果可为土地利用规划和制定多尺度水质保护措施提供重要信息。
