Study On The Mechanism Of Consumption In Yichang Irrigation Sub-district Of Irrigation District Of Inner Mongolia Along The Yellow River

This thesis is based on "Study on the Mechanism of Water Balance of Representative Areas", the third sub-task of "Study on the Mechanism of Water Balance and Consumption in Irrigation Districts of Ningxia and Inner Mongolia along the Yellow River", which belongs to the program of the national nature and science fund, and chooses the biggest irrigation sub-district of irrigation district of Inner Mongolia along the Yellow River-Yichang irrigation sub-district. The transformation of the water, which flows into this area, is very complex, and measure is difficult, so the mechanism of consumption is not clear, the data of water use is not full, and the utilization rate of water is very low. One more thing, the distributing of salinity is not well-proportioned and the evapotranspiration in this area is very intense, which lead to serious salinization. So studying the water balance and mechanism of consumption of this area and grasping the transformation and consumption of water in the process have important practical significance. At the same time, this thesis offers reference to grasp deeply the rules of water utilization and consumption and the mechanism of water balance in irrigation districts along the Yellow River.The study on the water balance of this area is the emphases and innovation in the thesis. The author has surveyed the parameters and the influencing factors of water balance of water resources system in Yichang irrigation sub-district of irrigation district of Inner Mongolia along the Yellow River. Using the concerned data of 1990~2002, the author studied water balance of the whole area with water balance method and the Penman-Monteith Equation, and analyzed groundwater balance of this area with water balance method and the Groundwater Evaporation Equation. In addition, the author quantitatively analyzed the relations of mutual restriction and transformation of balance factors, and revealed the mechanism of water balance and consumption in irrigation sub-district along the Yellow River, which is influenced by human activities. The main content of this thesis are as follows:1. Using irrigation period and annual period as time unit respectively, the author set up the water balance model of the whole area and the water balance equation, and studied water balance as well as the transformation relation of its parameters of the whole area inYichang sub-district with water balance method, and forecast the crop coefficient of this area by combining the Penman-Monteith Equation.2. Using irrigation period and annual period as time unit respectively, the author set up the groundwater balance model and its equation, and analyzed groundwater balance as well as the transformation relation of its parameters of this area with water balance method, and simulated the relation curve of groundwater evaporation coefficient and groundwater table by combining the Groundwater Evaporation Equation.3. Using annual period as time unit, the author set up the nonfarming area-farming area-water area water balance model and the water balance equation of each area, and researched water balance of farming area, nonfarming area and water area with circling the soil water, and the condition of water transportation from farming area to nonfarming area, from farming area to water area.4. Using annual period as time unit, the author studied salt balance of the whole area in Yichang irrigation sun-district and salt balance of all kinds of soil in this area with circling farming area.