Effects Of Apple Orchard Surface Mulching On Seasonal Water Consumption And Yield Of Fruit Trees

Natural precipitation is scarce in the apple producing areas of Shaanxi,and 90% of apple orchards have no irrigation conditions,which belongs to the typical rainfed farming area.Moreover,regional natural precipitation and apple water demand have suffered dislocation of spatiality.Therefore,how to utilize the precipitation resources efficiently is the key problem to be solved urgently for high and stable yield of dry land apple in this area.Mulch is an important measure to allocate soil moisture in agricultural production.In this study,the dwarf apple in Weibei dryland of Shaanxi was taken as the experimental material.Based on the field observation and laboratory analysis,the features of soil water and heat under different mulches,effect of mulch on temporal and spatial adjustment between precipitation and fruit tree water requirement,effect of water consumption of apple,effects of different mulches on yield and quality of apple,and water use efficiency of fruit trees were discussed,to provide scientific basis for soil moisture management in orchard under mulches.The main results were as follows:(1)Mulches have different effects on soil moisture in different layers of orchard.Cloth mulching has the greatest influence on soil moisture in the 0-20 cm soil layer,while straw mulching has the greatest influence on soil moisture in 0-80 cm soil layer.(2)Mulches increased the transpiration of fruit trees significantly.In the whole growth period,comparing to clean tillage,cloth mulching and straw mulching increased transpiration by 25% and 18%,respectively.At different stages of fruit tree,different mulches have different effects on transpiration water consumption of fruit trees.Comparing to clean tillage,the evapotranspiration of fruit tree in cloth mulching were increased by 32% and 56% at the flowering stage and the shoot growth stage,respectively,and straw mulching increased by30% and 17%,respectively.(3)Mulches have the effect of remarkable water retention.In the dormant period of fruit trees,comparing to clean tillage,the evaporation of straw and cloth mulches decreased by50.4% and 55.6%,respectively.Soil water storage in the 0-300 cm soil layer increased by11.1% and 12%,respectively.The relationship between soil water supply and fruit tree water requirement during spring drought period were coordinated.In the fruit growing period,clothand straw mulches increased soil water storage by 17.3% and 13.2%,respectively.(4)Mulches can improve the branch structure of fruit trees,improving the yield and quality of fruit trees.Comparing to clean tillage,the yield of fruit trees with straw and cloth mulches increased by 30% and 28.2%,respectively.Under the different mulches,the fruit shape index of fruit was significantly increased,the soluble solid content was increased,and the titratable acid content was reduced.(5)Mulches improved the water storage efficiency of the orchard soil and the utilization rate of precipitation.Comparing to clean tillage,cloth and straw mulches improved 11.3%and 20.6% of soil water storage efficiency,and precipitation utilization increased by 27.4%and 29.8%,respectively.