| The jujube industry is one of the important pillar industries of Xinjiang’s economic development,which also have the most resource advantages and development potentiality.At present,water resource shortage and unreasonable irrigation management system of jujube trees restrict the development of jujube planting industry.Therefore,this paper taking 7-year-old gray jujube trees as the research object,the field information was collected by soil moisture measurement system(TRIME),small automatic weather station,and CIRA-3photosynthetic apparatus,and the variation rule was analyzed.Selecting soil moisture content,canopy temperature difference,and stomatal conductance as irrigation decision-making indicators,a multi-source information irrigation decision-making model constructed based on D-S evidence theory.The irrigation decision model can synthesize multiple field information,diagnose the water status of jujube trees,judge the irrigation time and carry out irrigation time,which provided theoretical support for the realization of precision irrigation of jujube trees and solutions for alleviating the problem of local water shortage.The conclusions of this paper are as follows:(1)The variation laws of irrigation decision indexes were clarified under different water treatment conditions(The C1 treatment was 15 m~3/mu,The C2 treatment was 20 m~3/mu,and The C3 treatment was25 m~3/mu).The variation range of soil water content in daily scale was small,and the soil water content in irrigation cycle scale under different water treatment conditions showed a significant decrease.Soil water rate in the 20-60 cm soil layer was used as the mean value which was more reasonable.On the daily scale,stomatal conductance firstly decreased,then increased and then decreased,and all the three treatments reached the peak value around 18:00.When water content was suitable,the most important meteorological factor affecting stomatal conductance of mature jujube leaves in Aksu area was solar radiation followed by saturated water vapor pressure difference.The canopy temperature difference was more sensitive to the change with time on sunny days,and its minimum value appeared between 13:00 and 14:00 noon.Therefore,the canopy temperature difference in the sunny days was used to judge the water shortage of jujube trees.(2)The irrigation decision model based on multi-source information fusion had a good performance for better yield of mature jujube trees and lower water consumption.Three treatments were compared:the optimal irrigation system(T1),the decision-making model based on the lower limit of soil water(T2),and the decision-making model based on the fusion of multi-source information(T3).The water abstraction ratio of T1 treatment was the greatest,that of T2 treatment was smaller than other treatments,and the yield of T3treatment was the largest.Compared with T1 treatment,water consumption was reduced by 78.04m~3/mu;the yield was reduced by 16.67 kg/mu and water using efficiency of crops was increased by 17.95%in T2treatment.Compared with T1 treatment,the abstraction ratio decreased by 22.88 m~3/mu;the yield was raised by 33.33 kg/mu and water using efficiency of crops was increased by 12.90%.Considering production and water saving,the irrigation decision-making model based on multi-source information fusion shows a good applicability. |
