China Water Resources Pearl River Planning Surveying & Designing Co, Ltd, Guangzhou 510610, China.
School of Engineering, Anhui Agricultural University, Hefei 230036, China.
Int J Environ Res Public Health. 2020 Apr 1;17(7):2400. doi: 10.3390/ijerph17072400.
Continuous water-level decline makes the changes of water quality in reservoirs more complicated. This paper uses trend analyses, wavelet analysis and principal component analysis-multiple linear regression to explore the changes and pollution sources affecting water quality during a period of continuous reservoir water level decline (from 65.37 m to 54.15 m), taking the Biliuhe reservoir as an example. The results showed that the change of water level of Biliuhe reservoir has a significant 13-year periodicity. The unusual water quality changes during the low water level period were as follows: total nitrogen continued to decrease. And iron was lower than its historical level. pH, total phosphorus, and ammonia nitrogen were higher than historical levels and fluctuated seasonally. Permanganate index increased as water level decreased after initial fluctuations. Dissolved oxygen was characterized by high content in winter and relatively low content in summer. The pollutant sources of non-point source pollution (PC1), sediment and groundwater pollution (PC2), atmospheric and production & domestic sewage (PC3), other sources of pollution (PC4) were identified. The main source of DO, pH, TP, TN, NH-N, Fe and COD were respectively PC3 (42.13%), PC1 (47.67%), PC3 (47.62%), PC1 (29.75%), PC2 (47.01%), PC1 (56.97%) and PC2 (50%). It is concluded that the continuous decline of water level has a significant impact on the changes and pollution sources affecting water quality. Detailed experiments focusing on sediment pollution release flux, and biological action will be explored next.
连续的水位下降使得水库水质变化更加复杂。本文以碧流河水库为例，采用趋势分析、小波分析和主成分分析-多元线性回归的方法，探讨了连续水库水位下降（从 65.37 米降至 54.15 米）期间影响水质变化和污染来源的因素。结果表明，碧流河水库的水位变化具有显著的 13 年周期性。在低水位期间，水质异常变化表现为：总氮持续下降，铁含量低于历史水平；pH 值、总磷和氨氮均高于历史水平，并呈季节性波动；高锰酸盐指数在水位初始波动后随水位下降而增加；溶解氧的特征是冬季含量高，夏季含量相对较低。确定了非点源污染（PC1）、沉积物和地下水污染（PC2）、大气和生产生活污水（PC3）、其他污染源（PC4）等污染源。DO、pH 值、TP、TN、NH-N、Fe 和 COD 的主要来源分别为 PC3（42.13%）、PC1（47.67%）、PC3（47.62%）、PC1（29.75%）、PC2（47.01%）、PC1（56.97%）和 PC2（50%）。研究表明，连续的水位下降对影响水质变化和污染来源的因素有显著影响。下一步将重点探索沉积物污染释放通量和生物作用等详细实验。
