Underground Water Resources Elevation And Water Table Regulation Study For QingTongXia Yellow-river Irrigation In Ningxia Province

Qingtongxia irrigation district, a large irrigation district in China, is an important base for crops, energy, and heavy chemical industry. It has been channeling the Yellow-river water for irrigation for more than 2000 years. There is still an extensive arable land left unused due to the acute conflict of supply and demand resulting from the great shortage and low efficiency of water resources. Furthermore because of low water table, the high salinity of the field is now serious. After years of development and renovation, it is now a center for agriculture, industry, and economy in Ningxia province. However, the problems related to water resources are still left unsolved, and this has been the biggest barrier to the sustainable economic development of this irrigation district.This paper evaluates the underground water resources and its safe levels of miming, and then studies the availability of molepipe drainage, a kind of practical underground water regulation technique.Starting with the elevation of underground water resources and a safe level of mining through variable system theory, this paper analyzes the conditions of underground water resources based on the well-studied determination method of determining the two hydrographical coefficients: rainfall infiltration replenishment rate and irrigation replenishment rate. Then considering irrigation, rainfall, drainage and other related factors, a mathematical model is set up for the calculation of underground water storage,exploitation on water regulation. After analyzing the adaptability of molepipe drainage, an underground water table regulation is given out. Finally, the efficiency of the drainage technique is determined after its comparison with gutter drainage and vertical drainage, and deep research on the effect of molepipe drainage on water table in a typically selected area.