Optimized Irrigation Regime Of Rice Under Dry Seeded And Thinly Populated Cultivated Pattern

The thesis is the sub-project of the task named "The studying on water-saving irrigation sub-region pattern of Hei Longjiang dry farming and thinly populated rice, which is the scientific research project of the Water Resources Department of Hei Longjiang province. We wish to approach a new water-saving and high-yield rice cultivated model for mid-area, provide theoretical basis for regional water resources sustainable using, and furnish fresh train of thought for latter compiling water consumption data.Mid-area is the main grain producing area of Hei Longjiang province, there are 30,000hm2 paddy field in it. Dry seeded and thinly populated rice have such characteristics like water-saving, fertilizer-saving, high economic benefit, and large potentiality for increased production. For the paddy field extended in recent years, all these have made the inconsistency in water resources developed than ever before and have become a significant issue hindered local social and economic development. For these reason the experiments to research water consumptive regularity in field period, we can deduce economic irrigation quota from input-output model. The key issue we study is to seek water-saving and high-yield irrigation regime.The task investigates rice water consumptive experiments by SPAC theory and fundamentals of irrigation under dry farming and thinly populated cultivated model. The paper construct many mathematic models suitable for 2-to-3 accumulated temperature region through analyze actual measurement, such like water requirement model (include the correlation between water requirement and meteorological factors), seepage model, the regularity of water requirement, seepage and water consumption in field period. Study daily water consumption by time series analysis. Provide the absolute value and relative magnitude two kinds model under full irrigation and deficient irrigation two. different conditions. The relative magnitude model is raised from full growing period (D-K model) and stages two angles. By contrast Jensen, Minnas, Blank, Stewart and Singh five stage relative models, we think that Jensen model is the most suitable model to this area, at the same time seek the gray productive regularity of water sensible index. The paper find there have great water-saving potentialities in irrigation after research on rice economic irrigation quota from input-output angle, we also go further into themultiple economic irrigation quota.We reach the conclusion that the moistening irrigation is the optimized irrigation regime of cold zone rice through contrast yearly irrigated experiments data and fuzzy comprehensive judgment. By using tabulation method we inquire into the normal year optimize irrigation regime based on the water consumption regularity and economic irrigation quota ascertained ahead. Through use two-dimension dynamic programming we calculated the optimized irrigation regime under deficient irrigation condition, at the end by use orthogonal regression analyze the optimize irrigation regime under water-fertilizer coupled condition, we deduce yield-water and fertilizer-water correction model and water-fertilizer coupled effect model.