Study On Mulched Drip Irrigation For Corn Growth In Yaoba Well Irrigation Area,Alxa Left Banner Of Inner Mongolia

By check experimental investigation of dripping irrigation under plastic film, this thesis is taking Yaoba Irrigated Area as a test site to test the influence of different water and fertilizer to corn’s water consumption pattern, growth dynamic, output and production efficiency of water and fertilizer, targeting on the practical outstanding problems in this area in Alxa Left Banner of Inner Mongolia, such as the continues declining of the underground water lever, low efficiency of irrigation water utilization and water supply contradiction between industry consumption and agricultural consumption. From the experimental investigation, the best water and fertilizer combination has been obtained and the water saving efficiency analysis have been conducted, which has provided a theoretical basis to the high efficient water saving for local staple crops to remit the local crisis of water resources.The followings are the main research conclusions:(1) Taking check experimental principle, the irrigation norm has been divided into three group by their level:High, Middle and Low with each group also been divided into three group by their high, middle and low level of nitrogenous fertilizer. The drop irrigation for open field has been set as the comparison group to study the water demand pattern for corn growth under different water and fertilizer condition. The study has shown that the critical period of water demand for corn with drip irrigation under plastic film is between elongation stage and tasseling stage. It is in tasseling stage that the water demand is in maximum compared with all other growth stage and in seeding stage that the water demand is in minimum. In different treatment seeding stage and tasseling stage, the average value of water demand in total water demand is respectively 14.27% and 32.04%. The order of average daily water deprivation in each growth stage is:elongation stage>tasseling stage>watery stage>maturation stage>seeding stage.(2) Taking check experimental principle, the irrigation norm has been divided into three group by their level:High, Middle and Low with each group also been divided into three group by their high, middle and low level of nitrogenous fertilizer. The drop irrigation for open field has been set as the comparison group to study the corn growth dynamic along its growth stage under different water and fertilizer condition and to fit the function relationship between corn height, LAI, dry matter accumulation amount and water & fertilizer by analysis which taking maximum plant height, maximum LAI index, maximum fresh weight and maximum dry weight in different treatment as dependent variables and taking irrigation water amount and fertilizing amount as independent variables.(3) Taking check experimental principle, the irrigation norm has been divided into three group by their level:High, Middle and Low with each group also been divided into three group by their high, middle and low level of nitrogenous fertilizer. The drop irrigation for open field has been set as the comparison group to study the corn output and water and fertilizer utilization ratio under different water and fertilizer condition. The function relationship between corn output and water and fertilizer has been fit by analysis and the best water and fertilizer combination for corn output under different water and fertilizer condition of dripping irrigation under plastic film are:irrigation amount being 343m3/667m2 and nitrogen fertilizer rate being 25.3kg/667m2.(4) By comparing the irrigation amount, fertilizing amount and output of the corn with normal surface irrigation method and drip irrigation under plastic film method in the local area, the results are: compared with the local drip irrigation under plastic film method, the best water and fertilizer combination in drip irrigation under plastic film experiment can save the water 166 m3/667m2 with the ration being 32.61% and the output is increased by 16.84%; compared with the normal surface irrigation method, water saving can be 257m3/667m2 with the ration being 42.83% and the output is increased by 14.42%. From the result, it can be seen that the water saving and output increasing is more than obvious, hence the the best water and fertilizer combination in drip irrigation under plastic film has a broad application prospect.