| The release of phosphorus from the sediments mainly caused the algal booms andeutrophication in our country. In this thesis, a typical shallow river landscape for SouthLake of Handan was chosen as the subject investigated. The spatial and temporalcarnations in forms of fractions and possible sources were investigated. And furtheranalyzes the overlying water-sediment interface phosphorus transformation of themigration process and influence factors. To provide a reliable theoretical basis for thestudy of the same type of shallow lakes for phosphorus transfer and control in the citylandscape lake.In this study, South Lake water quality was analyzed from different angles index ofthe concentration pollutants. It is obvious that there had same change rule about TPbetween overlying water and sediment in Spring and Summer, but the regularity is notobvious in Autumn and Winter. South Lake annual average water eutrophication indexwas74.873. At present it has reached the level of eutrophication.The South Lake water quality evaluation methods were analyzed according to themerits of the water environmental quality assessment standards. Decreasing organicpollution load and strengthening hydrophytes management are the effectual measuresfor internal pollution control in South Lake.The method improved the real objectivebasis for the entire evaluation. Accurately reflect the situation of water pollution, theresults of the impact of pollutants on the lake, providing a scientific basis for planningprotection, water management and other functions water.The concentrations of total phosphorus in water ranged from0.130mg/L to0.954mg/L, the annual concentration is0.386mg/L in South Lake of Handan. Numericalrange is large. The trend of the average concentration of composition total phosphorusin overlying water: S3>S6>S7>S1>S5>S2>S4,(S represents the sampling point).Analysis from the time distribution, the content of TP in Spring and Summersignificantly higher than in Autumn and Winter. At the same time, the of TP in wateralso changes with the seasons.The results showed that TP enrichment level in surface sediments of South Lakewas ranged from540mg/kg to2072mg/kg. In general, various forms of inorganicphosphorus ranged as follows: Ca-P>O-P>Al-P>Fe-P>Ex-P. Inorganic phosphorouswas the main phosphorus source of internal pollution in South Lake. From the time, in terms of IP content have: Summer> Autumn> Spring> Winter. The correlation of eachphosphorus form was analyzed with linear regression method. Under α=0.05level,there was direct relativity between Fe-P and Ca-P. Under α=0.01level, Ex-P hadevident relativity with Al-P, Fe-P, O-P and TP. Al-P had relativity with Ca-P and TP. Therelationship between TP and Org-P could be well represented by the linear function.Reducing organic pollution load and strengthen the management of aquatic plant is aneffective way to control the endogenous pollution of South Lake.Different physical and chemical conditions effect the migration and transformationprocess of phosphorus in sediments were also discussed. The release rate of phosphorusrelease from sediment increased with the increase of the overlying water phosphorusconcentration, temperature and pH value. The physical environment of lake wasimpacted by precipitation process more obvious, the phosphorus content was notobvious. Rainfall depressed the process of sediments to overlying water adsorption ofphosphorus.Through the study of transformation and migration of phosphorus in South Lake ofHandan, it provided the reliable and scientific basis for water resources planning,management and the control of water eutrophication of river landscape shallow lakes. |
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