| In China's western Gansu Minqin oasis areas, the shortage of water resources and low utilization of agricultural water-fertilizer are the main problems of agricultural production restrictions. In recent years, farmland in the region to improve water use efficiency of water-saving irrigation technology research and development of the crop in the region to effectively improve the water environment, and improve irrigation water use efficiency has played a significant role. But at the same time saving ways to improve crop nutrient use efficiency, especially in water-saving irrigation water and nitrogen under the conditions of the coupling effect, in recent years become a hot issue in academic research, as currently, although some research results, but an oasis in the desert The study also relatively small area. Cotton under different irrigation water and nitrogen coupling effect of the study, improve the region for effective water and nitrogen use efficiency of cotton to improve the soil environment has important theoretical and practical significance. Based on the Minqin oasis Daejeon cotton irrigation district, systems research and analysis of cotton under different irrigation water and nitrogen coupling effect, the main conclusions of the pilot study are as follows:(1) The coupling effect of water and nitrogen under different furrow irrigation patterns shows that water and nitrogen application rate increased in the three furrow irrigation patterns will help improve cotton yield, but FFI limit the effects of water and nitrogen play, AFI and CFI not significant differences in the effects of cotton yield. Cotton NUE under different furrow irrigation patterns, increased irrigation and control fertilizer application can significantly improve, the promotion of AFI exert effects of nitrogen, and limits the effect of FFI. Cotton WUE under different furrow irrigation patterns, increased nitrogen application rate and control the volume of water can enhance the promotion of WUE, compared with the CFI, AFI has promoted exert effects of water and nitrogen, FFI reduce the effects of water and nitrogen play. The coupling effect of water and nitrogen in furrow irrigation shows that AFI most can promote the coupling effect to play, and promote cotton.efficient use of water and nitrogen. (2) Cotton groups physiological target changes in laws under different furrow irrigation patterns research, the use of the model f=a*exp(-0.5*((T-T0)/b)2) simulation, model parameters and simulation of high precision and stability. Leaf area duration(LAD), crop growth rate (CGR), net assimilation rate groups (NAR), leaf area index (LAI) of the dynamic simulation studies show that the cotton LAD, CGR, NAR, LAI are with the amount of nitrogen application and irrigation increased significantly improve, one of AFI's LAD, CGR, NAR biggest upgrade, but under high-fat high-water must be inhibited. CFI biggest upgrade of LAI. FFI various groups physiological target were significantly inhibited. Based on cotton groups physiological target changes in the law, as well as biomass, yield relations, draw the cotton group performance at a low fat, low-water situations AFI and CFI than FFI, in manure, water AFI and CFI cases better than FFI , high-fat, high-water situations CFI and AFI is superior to FFI.(3) The law of nitrogen uptake by the model (f=a*exp(-0.5*((T-T0)/b)2)) under different furrow irrigation Analog cotton nitrogen content in various organs, as well as the target of cotton nitrogen absorption changes fitting model parameters are stable and high precision. Total nitrogen content of various organs of cotton (N) under AFI, the proportion of N derived from fertilizer (Ndff) and nitrogen absorption rate (NAR) were not significantly different, in the AFI nitrogen on cotton smaller impact absorption to water conservation and promotion of cotton nitrogen uptake of water and nitrogen coupling effect, improve nitrogen use efficiency of cotton (NUE). fixed every furrow of the organ to absorb nitrogen and nitrogen content were significantly lower target to limit the nutrient uptake of cotton and reduce the NUE. furrow irrigation of cotton nitrogen absorption, the turn of every furrow irrigation can most effectively coupling effect of water and nitrogen to promote the nitrogen absorption and utilization.(4) Different furrow irrigation of cotton root zone water and nitrogen transport studies have shown that the root zone furrow irrigation of cotton on nitrate content with the overall fertility decline over the period. AFI nitrate content of the profile with the irrigation and nitrogen application rate increases, with increasing depth of soil profile and decreased the content of nitrate mainly in the cotton root system within the scope of the effective absorption. CFI profile nitrate content of the irrigation water increased with the decrease, and with the increase in soil profile and increased the depth. FFI irrigation ditch nitrate content did not change was not significant, with the irrigation ditch water nitrate content increased significantly upgrade. Furrow irrigation of cotton root zone changes of ammonium: AFI with the water content of the profile and growth increased, with the depth profile did not change significantly. CFI with the profile of the surface water content and growth increased, deep content is not significant. FFI surface of the profile with higher levels of ammonium nitrogen, deep low.(5) The coupling effect of water and nitrogen under different drip irrigation patterns, indicating that 1 lateral 4 rows affected by water stress, exert inhibiting effect, and 2 laterals 4 rows and 2 laterals 6 rows with appropriate water, 2 laterals 4 rows of nitrogen fertilizer to promote a play, 2 laterals 6 rows to play they are restricted in nitrogen. Show that the 1 lateral 4 rows and 2 laterals 4 rows to increase the volume of nitrogen fertilizer and irrigation will help improve cotton yiled, with 2 laterals 6 rows increased irrigation and fertilizer control in favor of increasing cotton yiled. Three patterns of drip irrigation to increase the volume of water and control of nitrogen application rate is conducive to improve NUE. 1 lateral 4 rows and 2 laterals 4 rows increase the amount of nitrogen application and reduce the volume of water will help improve cotton WUE, 2 laterals 6 rows volume control nitrogen and reduction water improve irrigation WUE. According to the coupling effect of different drip irrigation cotton, as well as cotton yield, NUE and WUE of the regression analysis, 2 laterals 4 rows of drip irrigation in cotton yield, WUE, NUE most can promote the play of water and nitrogen coupling effect.(6) Drip irrigation of cotton under different growth and development of the coupling effect of water and fertilizer, drip irrigation patterns in different leaf area index of cotton through the model(f=a*exp(-0.5*((T-T0)/b)2)) simulation, parameter stability and fitting accuracy higher. Model three drip irrigation of cotton LAI affected by nitrogen application rate than to increase the amount of nitrogen fertilizer and irrigation can significantly improve, the professionals, cotton LAI of the inside rows and outside rows as follows: 2 laterals 6 rows > 2 laterals 4 rows > 1 lateral 4 rows. 1 lateral 4 rows of cotton by the effects of water stress, root growth, the ground dry matter, boll number per plant, seed cotton production to a certain extent all of the inhibition. 2 laterals 4 rows fertilizer can increase the effective promotion of cotton nutrient absorption and dry matter accumulation of boll number per plant, seed cotton yield was significantly higher than all with 1 lateral 4 rows and 2 laterals 6 rows. 2 laterals 6 rows cotton groups of ventilation and light transmittance decreased, cotton growth and development must be the extent of inhibition, but the ground dry matter, boll number per plant, seed cotton yield so as to increase and improve the level of water and fertilizer.(7) The law of nitrogen absorption in different drip irrigation, the use of the model f=a*exp(-0.5*((T-T0)/b)2) simulation, model parameters and simulation of high precision and stability. The development of cotton roots and water-nitrogen transport was inhibited under 1lateral 4 rows mode, Root nitrogen use efficiency increased with the nitrogen to reduce,the nitrogen content of cotton stems, leaves, bud and boll with increased fertilizer, The increasing trend gradually reduced, various organs nitrogen content with the increased water significantly increase nitrogen uptake. 2 laterals 4 rows of cotton with the nitrogen and water increased biomass accumulated significantly, enhance and promote the development of cotton roots and water and nitrogen transport, nitrogen uptake of cotton organs and significantly improve the utilization efficiency. 2 laterals 6 rows compared to 2 laterals 4 rows, root development is restricted, affecting the root system of water and nitrogen transport, to reduce the cotton organ nitrogen content, increase the amount of fertilizer and irrigation can promote nitrogen uptake of cotton, but the performance of groups, nitrogen uptake was inhibited.(8) Different patterns of cotton root zone drip irrigation water and nitrogen transport law, the distribution uniformity of the root zone soil water with irrigation increased significantly improve, with the fertilizer did not change significantly under three drip irrigation patterns. Root zone soil nitrate content in cotton drip irrigation, Nitrate content of film central decline with the increased water and improve with the increase in fertilizer. Film edge nitrate with the irrigation and nitrogen application rate did not change significantly. Film central and edge soil nitrate content with fertilization and irrigation increased significantly improve. Ammonium content of the root zone, affected by fertilization than by the irrigation. The root zone soil ammonium content, Film central and edge were increased with increased fertilization, with increased irrigation line 1 lateral 4 rows significant changes, 2 laterals 4 rows, 2 laterals 6 rows decreased the surface, deep content increased.
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