摘要
为明确星云湖主要入湖河流向湖体的氮素营养盐输送特征,研究以星云湖南岸4条主要入湖河流单元雨季与旱季不同形态氮素的监测数据为基础,系统研究了星云湖南岸主要入湖河流单元不同形态氮的入湖浓度时空变化及不同形态氮对入湖TN的贡献,并探讨了已建南岸带状调蓄系统入湖污染削减效果。结果表明:①星云湖南岸主要入湖河流单元TN浓度为1.1～18.69 mg/L,DTN浓度为1.88～8.61 mg/L,且农田径流污染导致雨季TN浓度均高于旱季。②南岸大多数入湖河流单元样点中氮素以NO_3-N为主,占TN 39.49%;PN和NH3-N含量相近,分别占TN的28.50%与24.75%;DON含量相对较少,占TN的9.97%。雨季NH3-N、NO_3-N及PN对入湖TN的贡献显著增加。③星云湖南岸四条入湖河流在经过调蓄系统调蓄后,TN浓度均呈现下降趋势,TN平均削减率达到32.35%。不同形态氮素削减效果以NO_3-N最佳,平均削减率达到58.22%;NH_3-N及PN削减效果相对不显著。④星云湖南岸带状调蓄系统应考虑不同形态氮污染季节性差异,并进一步与湖滨湿地串联,提升调蓄系统对NH_3-N与PN的削减效果。
Based on the wet and dry season nitrogen concentration data of the 4 south inflow rivers of the Xingyun Lake,this paper studied the spatial and temporal changes in nitrogen concentration of different fractions,discussed the pollution reduction effect of south rainwater regulation system,with a goal of providing scientific support for further control over pollutant input.The results show:(1)The change in total nitrogen(TN)concentration of the south rivers into the Xingyun Lake ranges from 1.1 to 18.69 mg/L,and the TN concentration in rainy season is higher than that in dry season because of the farmland runoff pollution.(2)The N concentration of the south rivers into the Xingyun Lake is given priority toNO3-N,averaging 39.49%of TN;the proportion of PN and NH3-N are similar,averaging 28.50%and 24.75%respectively;the proportion of DON is relatively low,averaging 9.97%of TN.The input amount contributions of NH3-N,NO3-N and PN increase significantly in the rainy season.(3)After regulating south rainwater system,the TN concentration of the 4 south inflow rivers show a trend of decline,reducing 32.35%on average.NO3-N reduction effect is most obvious,reducing 58.22%on average,in contrast to a relatively low reduction rate of NH3-N and PN.(4)The rainwater regulate system should consider seasonal differences of the nitrogen pollution with various forms,and further combined with lakeside wetland to improve the reduction effects of NH3-N and PN.
作者
孔燕
白晓华
KONG Yan;BAI Xiaohua(Yunnan Institute of Environmental Science,Kunming 650034,China;Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake Watershed,Kunming 650034,China)
出处
《水文》
CSCD
北大核心
2019年第1期60-65,共6页
Journal of China Hydrology
基金
云南省应用基础研究计划项目(2015FD075)
关键词
星云湖
河流
氮污染
调蓄系统
削减效果
Xingyun Lake
river
nitrogen pollution
rainwater regulate system
reduction effect
