摘要
滇池富营养化严重,蓝藻水华时有发生。滇池的污染治理受到各级政府的高度重视,尤其是近10 a治理工作取得明显成效。利用滇池近10 a (2011~2020年)国控水质监测断面的月度水质数据,研究了滇池水质的时空变化特征。结果表明:滇池草海水域,叶绿素a(Chl-a)、总磷(TP)、总氮(TN)的浓度范围分别为0.002~1.012,0.030~0.718,0.20~9.97 mg/L;外海水域,Chl-a、TP、TN的浓度范围分别为0.003~0.589,0.015~0.491,0.35~9.70 mg/L。滇池Chl-a浓度与五日生化需氧量(BOD;)及TP等指标显著相关。基于水质特征的聚类分析表明,滇池10个监测点位分为草海、外海2个类群,草海水质状况显著劣于外海。草海水域TP呈现持续下降趋势,TN在2011~2017年之间呈现波动下降趋势,而2018~2020年之间TN浓度波动上升,综合营养状态指数(trophic level index, TLI)在2016~2020年较2011~2015年显著下降。外海水域TP呈现持续下降趋势,TN总体波动下降;TLI在2011~2016年之间呈现逐年下降趋势,2017~2020年之间呈现先下降后上升的趋势。总体上,近10 a滇池水质逐步改善,综合营养状态总体下降,但近年TN有上升趋势,Chl-a浓度仍较高,建议采取措施在TP控制的基础上协同控氮,并推进滇池水生生态系统结构与功能恢复。
The eutrophication is a serious problem in Dianchi Lake, algae blooms occur occasionally.The pollution control of Dianchi Lake has been attached great importance by governments, especially in the recent ten years, and the water pollution control in Dianchi Lake has been vigorously promoted.Based on the monthly water quality data of state-controlled water quality monitoring section in Dianchi Lake in recent 10 years(from 2011 to 2020),this paper studied the spatio-temporal variation characteristics of water quality in Dianchi Lake.Dianchi Lake is divided into Caohai Lake and Waihai Lake by Haigeng dike.The concentrations of chlorophyll a(Chl-a),total phosphorus(TP) and total nitrogen(TN) in Caohai Lake area were 0.002~1.012 mg/L,0.030~0.718 mg/L and 0.20~9.97 mg/L respectively.The concentrations of chlorophyll a(Chl-a),total phosphorus(TP) and total nitrogen(TN) in Waihai Lake area were 0.003~0.589 mg/L,0.015~0.491 mg/L and 0.35~9.70 mg/L respectively.The concentration of Chl-a in Dianchi Lake was significantly correlated with BOD;and TP.Based on the hierarchical clustering analysis of water quality characteristics, the 10 monitoring points in Dianchi Lake were divided into two groups(Caohai Lake and Waihai Lake).The water quality of Caohai Lake was significantly worse than that of the Waihai Lake.The TP in the Caohai Lake water area showed a continuous decreasing trend, and the TN showed a fluctuating decrease from 2011 to 2017,while the fluctuation of the total nitrogen concentration increased from 2018 to 2020,and the trophic level index(TLI) decreased significantly from 2016 to 2020 compared with that from 2011 to 2015.The TP in the Waihai Lake showed a continuous decreasing trend, while the TN showed a fluctuant decline trend.The TLI showed a decreasing trend from 2011 to 2016,and showed a decreasing trend first and then rising trend from 2017 to 2020.In general, the water quality and trophic level of Dianchi Lake had improved gradually in the past decade, but the TN had an increasing trend in recent years, and the concentration of Chl-a was still high in the whole lake.It is suggested that measures should be taken to coordinate the control of TN on the basis of the control of TP,and promote the restoration of the structure and function of Dianchi Lake aquatic ecosystem.
作者
黄杰
王英才
邓晓庆
施择
杨春艳
HUANG Jie;WANG Yingcai;DENG Xiaoqing;SHI Ze;YANG Chunyan(Ecological Environment Monitoring and Scientific Research Center,Yangtze River Basin Ecology and Environment Administration of Ministry of Ecology and Environment,Wuhan 430010,China;Yunnan Ecological Environmental Monitoring Center,Kunming 650034,China)
出处
《人民长江》
北大核心
2022年第6期61-67,共7页
Yangtze River
基金
国家自然科学基金长江水科学研究联合基金项目“长江深大水库层化水体的多界面微生物地球化学过程及其环境影响调控研究”(U204020117)。
关键词
水质
综合营养状态指数
草海
外海
滇池
water quality
trophic level index
Caohai Lake
Waihai Lake
Dianchi Lake
