Study on Soil Water and Salt Effects on Cotton Growth with Light-Saline Water Drip Irrigation under Mulching

Drought and water shortage have become the dominant factors restricting the development of agriculture in south of XinJiang.The development and utilization of brackish water can effectively alleviate the shortage of water resources.The effect of soil salinity on the growth of cotton under different irrigation conditions is studied through the field experiment.The result shows that during the critical period of cotton growth,the soil moisture content increases with the soil layers until soil depth reaches 30 cm,then decreases when the depth reaches 45 cm,and finally increases after the depth is higher than 45 cm;the soil salinity is higher when the soil depth is less than 15 cm.However,soil moisture condition improves with the increase of irrigation frequency,which leads to the decrease of soil salinity.In addition,the effect of different irrigation water salinity on soil salinity is studied,the results show that soil salinity increases with irrigation water salinity generally;the relation among soil moisture,salinity and the physiological characteristic of cotton shows that higher soil salinity can constrain the growth of plant height and diameter,influence the process of leafing out,and quicken the detachment of cotton boll.The test result figures out that it minimizes the effects on the growth of cotton,even helps to promote it when the irrigation rate is 30mm and the irrigation water is mixed with the ratio of brackish water to freshwater 2∶1.