The Research Of Water Demand For The Economic Crops Of Grape And Grass In Hills Region

The dry hilly areas of cultivated land takes a great amount of the hole farmland in Zhenjiang ,the problem of poor drought resistance, Soil erosion and apparently seasonal drought are so outstanding.Becauce of this area can not receive the irrigation in time, Waste adequate resources of warm and sunsine in the area,which would reduce the crop yield and quality.According to hilly areas of economic crops for water-saving technologies and equipment Research,which need to get water demanding information and crop irrigation model. The two cash crops including grape and grass planted in large scale in this area were studied. Thought experiment and theory analysis,the models of water deficit of and irrigation amount were established. The problems of when to irrigation and how much to irrigate were resolved. In this paper, the research work include the following aspects:1) Analysis of crop transpiration rate changed with the environmental factors such as the temperature, humidity and light intensity, established the model to forecast the transpiration rate. Researched the relationship of crop transpiration rate and soil moisture , the conditions of crop moisture are confirmed by the transpiration rate at the same time.2) Analysis of the regularity of canopy-air temperature changes with environmental factors. Gained the limits value of VPD in greenhouse of summer season. Established the model by the relation between canopy-air temperature and VPD, established a mode of water stress index (CWSI) by experienc,researched the reletion between CWSI and Soil moisture ,and used CWSI to diagnosis the water situation of crops.3) Using artificial neural network Matlab toolbox to combine transpiration rate with CWSI to diagnose the moisture situation of crop, for their respective limitations established two Classifiers.one is for recognizing crop moisture, other is for the degree of water deficit.4) Through irrigating Experimental, receiving the suitable amount for irrigation in the normal growth by using water balance equation.Through this research, it can use the sensor to acquisite weather conditions, the canopy temperature, soil moisture, and other datas, Using controller such as single piece controller or PLC to establish a automation control system by the model made this paper,which can achieve real-time, accurate irrigation purposes. It has a more important academic significance and practical value to ease the tension in hilly areas of water and to save the water resources.