Effects Of Straw Returning Amount And Border Field Specification On Cropland Moisture And Winter Wheat Growth

In order to further improve the benefits of straw returning to the field,reduce the problems such as the decrease of soil capacity and crop yield caused by the unreasonable use of straw.In this experiment,the effects of three straw returning levels and nine border field specifications on soil moisture,soil fertility and winter wheat growth and development were studied by field experiment.Finally,we selected the combination of straw return amount and border field specification,which is beneficial to wheat yield under the experimental conditions,to provide a reference for winter wheat planting in the experimental area.The main conclusions of this study are as follows:(1)In the period of wheat returning to green and jointing,the combination of9000kg/hm~2 straw returning amount and 2m border width×30m border length can properly promote the speed of water flow,effectively improve the distribution of irrigation water in the border,which is the best combination to improve the quality of irrigation under the experimental conditions.(2)During the growth period of wheat,straw returning improved soil water content and soil nitrogen content of 0-140cm in the harvest period.Among them,9000kg/hm~2straw can better meet the needs of water in different growth stages of wheat and promote the absorption and utilization of soil water and fertilizer;the combination of2m border width×30m border length has sufficient water content in the planned wet layer of soil after irrigation,and the total water consumption of crops from the return to green period to the harvest period is higher,which provides a good water supply for the formation of wheat yield.(3)Straw returning improved the growth characteristics of wheat plants,in which9000kg/hm~2 straw returning significantly increased the leaf area index,the height of the first tiller and the stem diameter of wheat;the change of border specifications mainly affected the plant height,stem diameter and the growth of wheat leaves after irrigation,in which the border specifications of 2m border width×30m border length had better growth indexes and stronger photosynthesis.(4)Compared with 18000kg/hm~2 straw,9000kg/hm~2 straw reduced the soil bulk density,reduced the ineffective evaporation of soil water in the later growth stage of wheat;there was no significant difference in soil bulk density,field water holding capacity and saturated water content in each growth stage of wheat by changing the border field specifications.(5)Appropriate amount of straw can effectively improve the yield components and water use efficiency.Compared with 18000kg/hm~2 straw returning,9000kg/hm~2straw returning increased yield significantly,which was 18.67%higher than that of no returning;wheat yield and water use efficiency under straw returning increased gradually with the increase of border length and the decrease of border width,and the three factors of yield composition increased in varying degrees.The grain yield of 2m border width×30m border length was significantly increased,and its 1000 grain weight,effective panicle number and water use efficiency were all at a high level.To sum up,under the experimental conditions,The combination of 9000kg/hm~2straw returning amount and 2m border width×30m border length can give full play to the advantages of straw returning and border irrigation,and improve the rational utilization of straw resources and the grain yield of winter wheat.