School of Civil and Environmental Engineering, Ningbo University, Zhejiang, 315211, China.
College of Materials Science and Engineering, Zhejiang University of Technology, Zhejiang, 310014, China.
J Environ Manage. 2021 Jan 15;278(Pt 2):111556. doi: 10.1016/j.jenvman.2020.111556. Epub 2020 Nov 1.
The Soil Water Assessment Tool (SWAT) was used for exploring the sources and retention dynamics of phosphorus nutrient in the river system of the Yong River Basin, China. The performance of the SWAT model was assessed. The retention dynamics of phosphorus nutrient in the river continuum and the factors contributing to those patterns were studied. The results showed that an average of 1828 tons of TP entered the river network of the Yong River Basin annually and in-stream processes trapped 1161 tons yr of TP in the watercourse, which accounted for 63.5% of the annual TP inputs. The TP retention rates in the river network ranged from 3.08 to 63.43 mg m day. An average of 666.9 tons of TP was delivered from the estuary to the East China Sea annually. The unit area riverine exports of TP ranged from 102.21 to 244.00 kg km yr. The river network is a net sink for TP and is going through a phosphorus accumulation phase. The results confirm that the river system has a considerable phosphorus retention capacity that is highly variable on a spatiotemporal scale. Because of the cumulative effect of continued phosphorus removal along the entire flow path, the retention fractions of phosphorus removed from all streams at the basin scale is considerably higher than that of an individual river portion. The variations of hydrological regimes, water surface area, unit area inputs of phosphorus, and the concentrations of suspended sediments have a great influence on phosphorus retention.
土壤水评估工具 (SWAT) 被用于探索中国永河流域水系中磷营养物的来源和保留动态。评估了 SWAT 模型的性能。研究了磷营养物在河流连续体中的保留动态以及导致这些模式的因素。结果表明，每年有 1828 吨 TP 平均进入永河流域的河网，而在河道中的水力学过程截留了 1161 吨 TP yr，占 TP 年输入量的 63.5%。TP 在河网中的滞留率范围为 3.08 至 63.43 mg m day。每年有 666.9 吨 TP 从河口输送到东海。TP 的单位面积河流输出量范围为 102.21 至 244.00 kg km yr。河网是 TP 的净汇，正在经历磷积累阶段。结果证实，该水系具有相当大的磷保留能力，在时空尺度上具有高度的可变性。由于沿整个水流路径持续除磷的累积效应，从流域尺度上所有溪流中去除的磷的保留分数明显高于单个河流部分。水文状况、水面面积、磷单位面积输入和悬浮泥沙浓度的变化对磷的保留有很大影响。
