水生态学杂志2016，Vol.37Issue(3)：19-25,7.DOI:10.15928/j.1674-3075.2016.03.003
洞庭湖氮磷时空分布及形态组成特征
Temporal-spatial Distribution and Speciation of Nitrogen and Phosphorus in Dongting Lake
摘要
Abstract
Nitrogen and phosphorus are the primary pollutants and main indicators of eutrophication in Dongting Lake.In this study,the spatial-temporal distribution of nitrogen and phosphorus in Dongting Lake were investigated and the relationships between nitrogen and phosphorus levels and phytoplankton growth were analyzed.The study was carried out in August 2014 (wet season)and January 2015 (dry season)at 16 sampling stations that covered inflowing rivers,Dongting Lake and outflowing rivers.Physiochemical parameters were determined both in situ and by laboratory analysis of water samples:SD,WT,Chl-a,CODMn ,TP,TN,TDP and TDN.Results show:(1)The concentration of TN ranged from 1.60 to 3.65 mg/L (average,2.25 mg/L),and the concentration of TP ranged from 0.060 to 0.359 mg/L (average,0.138 mg/L).The concentration of total particulate nitrogen (TPN)varied from 0.07 -1.39 mg/L (average,0.25 mg/L),and total particulate phosphorus (TPP)varied from 0.003 -0.172 mg/L (average,0.05 mg/L).(2)Temporally,the concentrations of nitrogen and phosphorus were higher in wet season than dry season.Spatially,the highest concentrations of nitrogen and phosphorus occurred at the out-lets of Dongting Lake,followed by the eastern lake area and then the western and southern lake areas.Obvious differences of nutrient concentration were observed among the four inflowing rivers.Particulate nitrogen and phos-phorus increased gradually from west to east,consistent with the spatial distribution of SS.(3)Total dissolved ni-trogen (TDN)and total dissolved phosphorus(TDP)were the primary species in Dongting Lake (88.0% TN and 66.7% TP).After Three Gorges Reservoir was first impounded in 2003,TDP increased from 20.0% to 35.6%of TP,but nitrogen speciation remained nearly the same.(4)With regard to the nutrient structure,TN /TP ratios at most sampling sites ranged from 10 -22.Correlations between nutrient levels (TN,TP,TDN and TDP)and Chl-a were not significant,indicating that algal growth is not limited by nitrogen or phosphorus in Dongting Lake.Con-centrations of nitrogen and phosphorus in Dongting Lake are far higher than the threshold value for eutrophication and promote algae growth.关键词
洞庭湖/氮/磷/时空分布/形态组成/相关分析Key words
Dongting Lake/nitrogen/phosphorus/nutrient temporal and spatial distribution/speciation/correla-tion analysis分类
生物科学引用本文复制引用
田琪,李利强,欧伏平,卢少勇,王丑明,张屹..洞庭湖氮磷时空分布及形态组成特征[J].水生态学杂志,2016,37(3):19-25,7.基金项目
国务院三峡办“三峡工程生态与环境监测系统-洞庭湖江湖生态监测重点站”项目（2014年）；湖南省环保科技计划项目（2014－16）。 （）
