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With the progressive development of the social economy, more and more countries and regions in many rivers, large-scale dams building a database. Reservoir to bring convenience and economic benefits of living at the same time, it also brings a range of environmental issues. Therefore, the \Cascade reservoirs in our country has been in a wide range of building, Guizhou Province, contains a wealth of water resources. Stabling large reservoirs in the Wujiang River Basin many minority. Cat jumping into a river as an important tributaries in Wujiang River is the oldest river in Guizhou Water Development, is the first in the country to complete the whole basin cascade hydropower development of the river, the whole river is divided into six development. For the the cascade reservoirs development of research in the country less, the whole basin cascade development is scarce. Therefore, research has important theoretical and practical significance of the reservoir on the cat jumping into a river and its watershed. This article in the July 2007 to June 2008 Maotiaohe River and its the cascade reservoirs above the three-year monthly sampling. Cat jumping into a river basin and its cascade reservoirs, total phosphorus (TP), soluble phosphate (SRP), particulate phosphorus (PP) and permanganate index (COD Mn ). The study found that: 1) compared with the Wujiang River mainstream, Maotiaohe basin has a higher phosphorus content. During the sample period, TP between 0.025-0.160mg / L, mean as to 0.072mg / L; SRP 0.008-0.068mg / L, mean to 0.026mg / L; TDP 0.001-0.108mg / L between the average to 0.040 mg / L; PP 0.001-0.092mg / L, mean to 0.028mg / L; 2) Maotiaohe of basin surface COD Mn spring 2.82-5.40 mg / L, mean to 3.17mg / L; summer 1.63-4.33 mg / L, the average value of 3.23 mg / L ; fall in the 1.69-5.13 mg / L, with an average of 3.19 mg / L; winter 4.23-8.77 mg / L, the average value of 6.33 mg / L. COD Mn on the whole basin are basically showing the downstream reservoir content is lower than the content of the upstream reservoir characteristics. 3) cat jumping into a river basin phosphorus and COD winter is generally high, may be greater than in winter due to the wet period of peaceful water water dilution Maotiaohe basin. In the winter, very little surface runoff, each reservoir began filling, Maotiaohe basin basic loss of self-purification of water, and therefore higher levels of biogenic elements. Even in winter cat jumping into a river basin in parts of dry phenomenon also fully illustrates this point. These phenomena karst areas the Maotiaohe basin the project water shortage, could not keep the water features. 4) the River Maotiaohe reservoir, spring and summer reservoir stratification period to the late summer and early autumn mix. 5) Hongfeng Lake and Baihua Lake in the summer and autumn, PP content less may fall Guiyang rainy season, fewer agricultural fertilizer applied; decrease in external contamination of the tributaries, and rain diluted the surface water body, The water flow rate accelerated, resulting in a decrease in PP content. SRP lower content in the summer, it may be due to the higher temperature in summer, adequate light, more suitable for the growth of algae, and various forms of phosphorus, soluble phosphate (SRP) is the most susceptible to algae absorbed. In the winter, the higher content of surface waters PP, SRP content, in the summer, SRP and PP content is not high, the Hongfeng Lake and Baihua Lake by external sources of pollution is more serious. The various reservoirs are exhibited with increasing water depth increases, the content of TP is highest at the bottom. Bottom sediment phosphorus release has some influence on the overlying water. 6) four reservoirs COD Mn variation higher winter peak occurred in March, and PP variation similar. Baihua Lake outside COD highest are surface water body, this is because COD sediment deposition purification mainly by the long residence time of water in the reservoir will gradually reduce as the depth of the changes in COD, COD content began to increase; into the bottom of the , may be due to the organic matter from Sediment freed, but also caused the increase of the COD content. And Baihua are the bottom highest content, this may be because the the Baihua bottom is in the extreme hypoxic state, caused by the microorganisms in the the Baihua bottom more perishable degradation. 7) Maotiaohe on all reservoirs in the eutrophic state, including red maple, flowers and Xiuwen reservoir has reached severe eutrophication, alleys kou Reservoir and Red Rock Reservoir in moderate eutrophication. 8) Maotiaohe basin the cascade reservoirs built phosphorus rejection, the more lower TP concentrations downstream. Description particulate substances accumulate and are deposited on the bottom of the reservoir. Spring, fall, winter interception of phosphorus in more than 40%, while only 25% of the summer interception of phosphorus. Description exogenous phosphorus input and surface runoff dilution of surface TP content Maotiaohe have a certain impact.
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