Forms of Nutrients in Rivers Flowing into Lake Chaohu: A Comparison between Urban and Rural Rivers

Water

Lei Zhang¹  Shiguang Shao³  Cheng Liu¹  Tingting Xu²  Chengxin Fan¹ 

[1] State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; E-Mails:;Department of Environmental Science, China Pharmaceutical University, Nanjing 211198, China; E-Mail:;College of Hydrology and Water Resource, Hohai University, Nanjing 210098, China; E-Mail:

关键词: phosphorus;    nitrogen;    river water;    sediment;    Lake Chaohu;   

DOI  :  10.3390/w7084523

来源: mdpi

【 摘 要 】

Nutrient inputs from rivers play an important role in lake eutrophication. To compare the forms characteristics of phosphorus (P) and nitrogen (N) in rivers flowing through rural and urban areas, water samples were collected seasonally from five urban rivers and six rural rivers flowing to Lake Chaohu, China. Higher total phosphorus (TP), particulate phosphorus (PP), soluble reactive phosphorus (SRP), and dissolved nonreactive phosphorus (DNP) concentrations and SRP/TP percentages were observed in urban rivers than in rural rivers, and PP/TP and DNP/TP ratios were lower in urban rivers than in rural rivers. The concentrations of total nitrogen (TN) and all N forms other than dissolved organic nitrogen (DON) were significantly higher in urban rivers than in rural rivers. NH₄⁺/TN levels were higher in urban rivers, whereas PN/TN and DON/TN ratios were significantly lower in urban rivers compared with rural rivers. NO₃⁻/TN and NO₂⁻/TN levels were similar between the two groups of rivers. TP, BD-P, and NaOH-P levels in urban river surface sediments were significantly higher than those in rural rivers. NaOH-P/TP ratios were significantly elevated in urban rivers, whereas HCl-P/TP and Res-P/TP ratios were significantly lower compared with rural rivers. Urban rivers have transferred large quantities of NH₄⁺ and SRP into Lake Chaohu, resulting in higher TP and TN levels and NH₄⁺/TN and SRP/TP ratios. Decreasing the input of NH₄⁺ and SRP into urban rivers is a high priority for mitigating eutrophication and algal blooms in Lake Chaohu.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.