Research On Less Or No Winter And Spring Irrigaiton On The Cotton Fields Of Soll Water And Salt Distribution And Cotton Growth

For ring tarim river basin land common salt, secondary salinization is serious, water resource scarcity,winter and spring irrigation quota is larger, the present situation of the waste of water resources is serious.This test under the condition of continuous cropping cotton drip irrigation, the main economic crop insouthern xinjiang cotton cotton49as the research object, take the winter spring differentiation processingmethod, the spring and winter irrigation on soil salt leaching, analysis of different irrigation waterdistribution characteristics of soil water salt and cotton physiological characteristics, preliminary determinereasonable winter spring norm, to reasonably determine the soil secondary salinization prevention andcontrol measures and provide scientific basis for the field moisture management, the following mainconclusions1. Research shows that the winter spring has the effect of leaching salt, with the increase of irrigationwater, deep salt tend to be leached into the soil, the upper desalination rate and depth of desalination is onthe rise. At the same time, with the increase of irrigation water, irrigation and soil moisture content, saltcontent and salt content difference is increased. For water and salt distribution under different irrigationquota analysis it can be seen that by different change range of soil moisture content, salt content, the largerchanges in the soil within0to40cm,40cm in depth of water content, salt content is strongly influenced byirrigation, the external environment.Under the same irrigation quota, winter irrigation on soil salt leachingeffect higher than that of spring water, if you want to pressure alkali cotton soil, winter irrigation can beused to achieve the goal of salt regulation. Through experiment, the T1, T2and T3desalination ratereached40.00%、51.07%、and60.05%, respectively, were effective.Different winter spring irrigation system in the whole stages in cotton phase at the same time, winterspring irrigation quota total higher processing, soil moisture content is relatively high in the wholestages;Under the condition of winter spring cotton salt content to present the following trend;Cotton fromseedling stage to a downward trend during the blooming period, the wadding stages rise phenomenon.2. Different winter and spring infuse water treatment on soil salt ion leaching, with the increase ofirrigation quota, the greater the leaching, of all the salt ions, irrigation on the soil of Cl-, K++Na+leachingthe strongest, winter spring on soil salt ion leaching performance for Cl-﹥K++Na+﹥SO42-﹥Mg2+﹥Ca2+﹥HCO-3. Salt ion migration with the movement of water in the soil, soil initial moisture content, saltcontent of soil moisture movement has a great influence, so it to fill in the soil after salt ion migration alsocan produce very big effect, for the winter and spring irrigation has a great influence. Analysis study, thegreater the winter and spring irrigation quota of soil salt ion leaching down more fully. 3. The growth period of winter and spring irrigation in film with drip irrigation of cotton seedlingemergence, plant height and yield are closely related. In growth period under the condition of irrigationfertilization management conditions consistent, with the increase of winter and spring irrigation quota,improve the germination rate, plant height growth speed is relatively fast, cotton yield increased, when thewinter and spring irrigation quota of3750m3/hm2and the corresponding yield is relatively high, up to6034.39kg/hm2, the winter and spring irrigation mode is better than that of other handling of the T2irrigation mode. Combining different winter and spring irrigation quota regulation effect of soil water andsalt, physiological indexes, yield and irrigation water use efficiency, a preliminary conclusion winter springirrigation mode for: winter irrigation1875m3/hm2and spring irrigation1875m3/hm2.