Research On Eco-environmental Water Requirement And Optimal Study Of Irrigation On RCSU In Huaibei Hilly Area In Jiangsu Province

More and more people become to accept the fact that the research of rainwater-collection-storage-utilization (RCSU), especially in some hilly areas, has been an effective measure to compensate for water shortage. According to the present situation of increasingly serious water resource shortage and deterioration of eco-environment in hilly areas, with the satisfaction of eco-environment water demand and irrigation water of crops, and in connection with the example of RCSU planning in Huaibei hilly area in Jiangsu province, the paper puts forward an optimization study on the project scale and the planting layout of RCSU, which offers a good reference to RCSU planning in hilly areas.At first, according to the characteristics and problems of eco-environment in hilly areas, on the basis of summarization of research on eco-environment water demand of the scholars both home and abroad, and taking Huaibei hilly area as study object, the paper analyses the composition of eco-environment water demand of in Huaibei hilly area and presents its calculation procedure. Then, The paper analyzes the water balance of the schemes with different come-and-used water guarantee rate and planting layout. Based on the analysis of rainwater collection and storage, outside water transfers and underground water exploration, with the consideration of the eco-environment water demand and irrigation water of crops in hilly areas, the paper puts forward an optimization study on the project scale of RCSU and presents an optimal method and its concrete steps. The results determine the optimal storage volume per mu and the proportion of the suitable paddy field and dry-farming corresponding to the irrigation design probability of 75% in hilly areas.At last, according to the random simulation of rainfall course of 75% inflow frequency based on the present rainfall data, the paper checks the optimal storage volume per mu of typical year. Therefore, the suitable optimal storage volume per mu after modification is fixed, which offers an important theoretic reference for RCSU planning in hilly areas.