Study The Effects Of Middle-Route South-to-North Water Diversion Project On Water Environment In Mid-Lower Reaches Of Hanjiang River

The distribution of water resources in our country is very non-uniform, and the north area is different from the south. The Middle-route South-to-North Water Diversion Project is a strategic solution to the problem.The Middle-route South-to-North Water Diversion Project plays an important role in promoting economic and social development and improving the ecological environment, but also will resut in significantly reduce of water resources itself in Mid-Lower Reaches of Hanjiang River, and will bring a series of water environment problems. While with the construction of the Four Compensatory Project, the Cascade Projects and Han to Wei River water diversion project,which will bring a few effects on the water environment. Bsed on the above-mentioned, it is a great pratical significance to study the topic.Based on " Study the Effects of Middle-Route South-to-North Water Diversion Project on Water Environment in Mid-Lower Reaches of Hanjiang River and countermeasures", a project supported by the Department of Water Resources in Hubei Province, the disseration takes the water environment in the regions along the mid-lower reaches of the Hanjiang River as its research subject, and a large number of meteorological data (rainfall, evaporation,temperature, etc.), flow and water level data, pollution data.water quality monitoring data of main blowdown outlet, the underwater topography data, the design and research reports were collected,making use of the findings done by other researchers, the mathmatic model and the methods of systems analysis to research respectively as well as systematicaily into the effects of Middle-Route South-to-North Water and Han to the Wei River Water Diversion Project on water environment in Mid-Lower Reaches of Hanjiang River.The probing study is done by the way of both learning the theoretical achievement from our predecessors and combining with practice.Although a lot of research works on the effects of water diversion projects to the downstream of intake area had made at home and abroad, the effects on ecological environment of the water diversion projects are slow, chronic, latent. It is difficult to be found without dozens of years, several hundred or thousand years or even a million years. Furthermore, the longer the distance water diversion, the larger its effects, the more complicated factors, integrated, ecological. So this dissertation chooses water environment effects as study topic, and the main research work is as follows:In the first chapter, background and significance of water enviornment study is provided. The effects of water diversion projects to the downstream of intake area at home and abroad are summed up. The basic projects overviews(the Middle-Route South-to-North diversion Project, the Four Compensatory Projects, the Cascade Projects, Han to Wei River Water Diversion Project, the water-supply areas and water-supply sources projects in the Mid-lower reaches of Hanjiang River) related with the paper are introduced. The content of water environment, water environment capacity and the calculation conditions are definiened. Finally the main contents, the technology line. of this paper are summarized.In the sceond chapter, the socio-economic profiles of the Mid-lower reaches of Hanjiang River including profiles of natural and socio-economic profile is briefly introduced,and it is the research socio-economic background.In the third chapter, the Wavelet analysis and mathematical statistics method are used to produce periodicity property. The Mann-Kendall, Spearman rank correlation test, linear regression analysis are used to analyze the evolution runoff trend of Dan Jiangkou reservoir and the main stations, and the causes of consecutive dry are be revealed in the 20th century 90 year. The correlation is built based on the a ten-days’average flow of the Shayang and Qianjiang station from 1990 to 2007, and other flood years such as 1964,1975,1983,1984, so the Dongjing River split ratio is scientifically developed. The effects of the flow, water level, flow rate and irrigation are also analyzed after water diversion in the Mid-lower reaches of Hanjiang River.In the fourth chapter, the discharge trend of point and non-point pollution is analyzed based on the full use of the national pollution census results in 2007. The pollution load is predicted in 2020,2030 according to survey results of the main blowdown outlet, and combination with the attenuation coefficient of pollutants into river.In the fifth chapter, one-dimensional hydrodynamic water quality model is used to simulate the effects of Middle-Route South-to-North and Han to the Wei River Water Diversion Project on Water Environment in Mid-Lower Reaches of Hanjiang River. Kmon4 exponent, NH3 concentration, NP concentration are selected to be water qulity indicators. Sixteen kinds of calculated conditions are combined according to the a long series of discharge of Dan Jiangkou Reservoir, water demand, pollution load in 2007,2020,2030,based on the built and planning projects including Middle-Route South-to-North diversion Project (9.5 billion m3), Han to the Wei River Water Diversion Project (1.0 billion m3), the Four Compensatory Projects, the Cascade Projects. The model Parameters are verificated from two aspects including water level and quality according to the series of hydrology and water quality in 2006-2007, which shows that the model has a high reliability. The analysis indicators is water qulity, water function zones, water environment capacity and irrigation, and combined with the effects of the flow, water level,flow rate and irrigation which are analyzed in Chapter 3. The main results are as follows:1 Stations Renovation projects——one of the Four Compensatory Projects, which is favorable to water environment of the Mid-lower reaches of Hanjiang River, and the water conditions are improved, and the irrigation guaranteed rate is increased at these irrigation areas along the Mid-lower reaches of Hanjiang River.Xinglong Cascade Project——one of the Four Compensatory Projects, which is double-headed to the water environment On one hand, the water level of the above reaches of Xinglong Cascade Project is raised, and the water conditions are improved, and water resources shortage conflicts are reduced, and the irrigation guaranteed rate is increased at these irrigation areas above reaches of Xinglong Cascade Project. On the other hand, the water quality is further deteriorated, the days to meet the objectives of the water function zones are reduced and the loss of water enviornment capacity is further increased.The Yangtze River to the Hanjing River Water Diversion Project——one of the Four Compensatory Projects, which is favorable to water environment of the Mid-lower reaches of Hanjiang River. Fistly, the water resources shortage conflicts are reduced and the irrigation guaranteed rate is increased at Dongjing River irrigation area through the water supply from the Yangtze River to the Hanjing River. Secondly, the loss of water enviornment capacity is reduced below the reaches of Gaoshibei (the outlet of The Yangtze River to the Hanjing River Water Diversion Project).2 The Cascade Projects are double-headed to the water environment of the Mid-lower reaches of Hanjiang River. On one hand, the water level of the above reaches of the Cascade Projects is raised, the water conditions are improved,the water resources shortage conflicts are reduced, and the irrigation guaranteed rate is increased at these irrigation areas above reaches of the Cascade Projects. On the other hand, the water quality is further deteriorated,the days to meet the objectives of the water function zones are reduced, and the loss of water enviornment capacity is further increased. The loss of water enviornment capacity are mainly concentrated in the reaches between the Danjiangkou reservoir and Gaoshibei with the construction of the the Cascade Projects.3 The flow, water level, flow rate, irrigation guaranteed rate, the days to meet the objectives of water function zones are further decreased considering Han to the Wei River Water Diversion Project after water diversion 9.5 billion m3, but the reduce rate is small. The Kmon4 exponent, NH3 concentration, NP concentration, the loss of water environment capacity are marginally increased, which shows that although water quality is further exacerbated, but the main factor is the Middle-Route South-to-North Water Diversion Project(9.5 billion m3).4 The NP concentration is increased more than the other indicators among Kmon4 exponent, NH3 concentration, NP concentration. The NP concentration is determinant to estimating the water quality category.5 The loss of water environment capacities of Xiangfan, Hanchuan, Zhongxiang reaches are larger than other reaches in the Mid-Lower Reaches of Hanjiang River.In the final chapter, innovation work of the whole paper is summarized, and suggestions for future work of water enviornment research are given.