| End of the Jindi River is the flood-prone part, where there are a large number of fertile farmland. It is the main grain-producing region of Shandong province and the grain base of China. Floods not only seriously threaten the life and property of people of both sides areas, but also take adverse effect on the surrounding area’s underlying surface, water environment, biodiversity, etc. In order to macro-allocate the water of Jindi river, they built the reservoir based on the flood control engineering at the downstream. It can not only realize the development and utilization of flood resources, but also produce great ecological, social and economic benefits.Through investigating the annual flood changes and eco-environmental evolution of Jindi river basin, and with the meteorological and hydrological observation data for years and field sampling monitoring data of water and soil, we discuss the influence produced by flood of Jindi river on agricultural ecological environment, such as underlying surface, water environment and biodiversity. While, we argument the significance of developing the production, improving the ecological environment and reducing the flood threat by using flood resources based on the present condition of engineering and put forward the existing problems and solving countermeasures when develop and utilize flood resources of Jindi river. The main conclusions are as follows:(1) The main reasons of leading to the flood resources rich at the end of Jindi River are the great interannual variation and annually uneven distribution of precipitation, concentrated and long time continuous rainfall duration, many flood disorders caused by serious sediment deposition or decrepit levee and the difficulty of water into the Yellow River.(2) The soil on both banks of the downstream of Jindi River is seriously affected by the water logging,which lead to the content of DDD in soil of both banks is higher than surrounding areas. There exist the phenomenon that soil salinization of inside is higher than outside at the same cross section of the river bank and the salinization is gradually reduced from inside to the outside, which will illustrate that the flood at the end of Jindi River has caused a certain degree of soil salinization. In addition, the of the levee alluvial flat ground soil nutrient content in addition to the total phosphorus, the content of soil nutrition at the flood land of the levee’s inside is generally higher than the outer cover except total phosphorus, such as total nitrogen, total potassium and organic matter.(3) Now, after years of supervision and management, although the pollution of Jindi River has relieved, but a certain circumstance of violation still exists in different time and some monitoring indicators. The water quality of Zhangqiu is affected by the Jindi River’s water, especially at the time that the rainfall is concentrated and large. As to the effect of dilution and purification of the river water, the water quality improved markedly at that time. The order of P values(comprehensive pollution index) for the section of Zhangqiu in different period times was dry period> level period > rainy period. The value of P is 1.549 during dry period belonged to heavy pollution and the water quality status is beyond the water quality standards of class IV. Level period for 0.807, the water quality situation belongs to the moderate pollution. The value of P is 0.684 for light pollution in rainy season. The order of P values(comprehensive pollution index) for different season was winter > spring > autumn > summer. Winter is the most polluted, and the value of P is 2.03 belonged to the serious pollution. Followed by the spring, the comprehensive pollution index is 1.06, and the water quality conditions belong to heavy pollution. The values of autumn and summer were 0.81 and 0.69, and the water quality was moderate pollution and light pollution, respectively.The water pollution status of Jindi River has improved in recent years. The P values of Zhangqiu located at the end of Jindi River showed a trend of decline companied with fluctuations from 2009 to 2013. The maximum comprehensive pollution index was 1.64 occurred in 2009, and the pollution is most serious beyond water quality standards of class IV. The minimum for 0.46 appeared in 2012, and all water indexes meet class IV.(4) Flood plain within the river bank and part of land at the end of Jindi River was overwhelmed by flood during flood seasons year by year, which caused certain losses of life and property of the surrounding people. After the water receded, the sediment deposit and the rubbish of water deposit come down causing environmental degradation and the spread of bacteria. Besides, the infiltration of the polluted water induces soil pollution. Accompanied with the emergence of the problem of soil salinization at the part of the levee seepage period, the agricultural ecological environment gradually deteriorated at submerged and surrounding areas.(5) There exist some problems when we develop and utilize the flood resources of the end of Jindi River, such as embankments, water pollution and management. Therefore, we must repair the existing flood control system, increase the intensity of controlling pollution, and systematize management system, in order to give full play to the comprehensive benefit of flood resources for the Jindi River.(6) Using the channel of the end of Jindi River to build the plain reservoir for the development and utilization of flood resources, it can reduce water loss and soil erosion, decrease the threat of soil salinization and improve the environment of underlying surface. Besides, it also can purify water body, reduce flooding and improve the water environment. More than, it not only can stabilize terrestrial and aquatic environment, increasing biodiversity, but also save the cultivated land, lower investment, increase the supply of water and reduce loss of flood disaster. At the end, it can promote the aquaculture and tourism, increase employment, and boost social and economic development.
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