Dynamic Changes of Eutrophication in East Dongting Lake and Reason Analysis
To understand the dynamics and causes of eutrophication in the East Dongting Lake region,we analyzed the dynamic changes of nutrient concentrations,chlorophyll a(Chla),the Integrated Nutrient Status Index(ΣTLI),and the relationships between Chla content and environmental factors using water quality monitoring data from 2017 to 2022.The results indicated that(1)the total phosphorus(TP)concentration in the waterway exceeded that in the main lake body,while the total nitrogen(TN)and Chla concentrations in the main lake body were higher than those in the waterway;(2)over the past six years,ΣTLI was equal to or greater than 50 in four years,indicating a mild eutrophic level,and was characterized by fluctuations,conversely,the ΣTLI in the waterway remained below 50 for six consecutive years,reflecting a medium nutrient level with a downward trend;(3)correlation analysis revealed that Chla concentrations in both the main lake body and the waterway were significantly positively correlated with water temperature(WT)and Secchi depth(SD),and negatively correlated with TN,additionally,Chla concentrations in the main lake body were significantly correlated with dissolved oxygen(DO);(4)the flow velocity of the waterway in East Dongting Lake was relatively fast,whereas the main lake body showed slower flow velocities.The eutrophication in both the waterway and the main lake body is closely linked to water velocity.
East Dongting LakenutrientsChlaIntegrated Nutrient Status Indexcorrelation analysis
万方数据
维普
