Study On Water Requirement Characteristics And Irrigation System Of Sprinkler Irrigation And Soybean In Southeast Of Lingnan Based On ISAREG Model

Inner Mongolia Hulunbeier area is one of the main soybean production bases in China.The stable production of soybeans plays an important role in China's food safety production and the promotion of local farmers' production and income increase.Sprinkler irrigation is one of the effective methods to increase water production in agricultural production in China.This paper mainly carried out research on soybean growth characteristics and irrigation system under sprinkler irrigation conditions in Hulunbeier Arong Banner,Inner Mongolia.Using field test method,soybean was used as test material,and the same irrigation number was used for different irrigation quotas.The actual agricultural production situation was not treated with irrigation(CK)as control treatment,and 4 different irrigation gradients were designed.The water consumption,yield,and crop water use efficiency of the whole growth period were studied separately.The reference crop evapotranspiration ET0 and the crop coefficient Kc were calculated through the local meteorological data of the current year,and the model was used to evaluate the actual irrigation system.This is an optimized choice.The following main conclusions were drawn from the research:(1)The soil moisture characteristics of soybean under different irrigation treatments were studied.It was found that under the condition of sprinkler irrigation,the soil moisture content of soybean increased with the increase of irrigation quota,and the variation range of soil water content was 15.74-25.67%.The water content in the growth period of 0-40cm has a large change range,and the water content of the deep soil is 40-60cm,and the water content is 60-80cm.The water consumption range of soybean during the growth period is 326.71-435.85mm.The average daily water consumption intensity was compared:pod stage>drum stage>flowering stage>maturity stage>branching stage>seedling stage.(2)The soil evaporation between sprinkler irrigation and soybean was 116.19-132.59mm,accounting for 29.68-39.21%of the water consumption during the growth period.The evaporation between soybeans is mainly when the soil surface is relatively wet after rainfall or irrigation.(3)The leaf area index of soybean with different sprinkling water amount showed a single peak change with the progress of growth process,and the leaf area index at the pod-forming stage was 4.9.The irrigation treatment during flowering and pod-forming period can significantly improve the physiological characteristics of soybean,which is the main growth of soybean.period.The logistic curve was used to fit the process of the accumulation of dry matter in the aboveground part of soybean with the growth period.(4)According to Pearson correlation analysis,meteorological factors and ET0 have a negative correlation between daily maximum,average,and minimum relative humidity and ET0.The correlation between daily rainfall and ET0 is weak;2m wind speed and ET0 are in the whole growth period and flowering stage.There was a significant positive correlation in the 0.05 interval.The crop coefficient of soybean was:Kc=0.43 in seedling stage,Kc=0.51 in branching stage,Kc=0.74 in flowering stage,Kc=1.01 in pod stage,Kc=0.63 in drum stage,Kc=0.44 in maturity stage,Kc=in whole growth period.At 0.63,the crop coefficient showed a trend of lower growth stage,higher growth period and lower stage during the growth period.(5)The ISAREG model was used to evaluate and optimize the local irrigation system,and the irrigation system under three years of dry year,flat water year and abundant water year was obtained.The optimal irrigation system for dry year was:irrigation time:June 17,July On the 2nd,July 11th,July 22nd,July 30th,the irrigation quotas were 32.8mm,36.1mm,48.7mm,52.9mm,43.1mm.The preferred irrigation system for Pingshui Year is:irrigation time:June 17,July 14,August 8,the irrigation quota is 30mm,42mm,34mm.The optimal irrigation system for Fengshui is:25mm in the early growth period,30mm in the mid-fertility period,and 35mm in the late growth period.The results can provide theoretical support for the implementation of soybean sprinkler irrigation water-saving irrigation technology in Hulunbeier area of Inner Mongolia,which is of great significance to realize the realization of local water-saving and production-increasing actions and the development of water-saving agriculture in the north.