| Drip irrigation,as an important measure for water and fertilizer integration technology,has the advantages of saving water and energy,saving labor and fertilizer,adapting to the soil and topography,and increasing the amount of production.Drip irrigation is a local irrigation,the uniformity coefficient of drip irrigation is an important performance index to measure the quality of drip irrigation.To achieve high yield of crops,irrigation uniformity coefficient of drip irrigation system needs to be maintained at a relatively high level to meet the needs of crops.Existing studies have shown that the current irrigation uniformity coefficient coefficient of drip irrigation system has a further reduction of space,and determine the corresponding uniformity coefficient of the determination method and proposed the value through the test,simulation and other methods.The effect of irrigation on crop yield is mainly achieved through soil.The growth and yield of crops are not only affected by soil moisture,but also affected by the uniformity coefficient of soil moisture distribution.Existing studies have focused on the relationship between irrigation uniformity coefficient and soil moisture distribution uniformity coefficient,and there have been few reports about specific relationship between uniformity coefficient of drip irrigation and irrigation uniformity coefficient of soil moisture,and in the different initial soil moisture content,the effect of irrigation volume and irrigation uniformity coefficient on the distribution of soil moisture remains unclear.In order to explore the relationship between the uniformity coefficient coefficient of drip irrigation and the soil moisture uniformity coefficient coefficient and tomato growth,by the effect of soil initial water and irrigation amount.This study was based on the cultivation of greenhouse tomatoes in the Northwest China,set 0.65(low),0.75(medium),0.85(high)3levels of irrigation uniformity coefficient,190mm(low),220mm(middle),and 250mm(high)3 irrigation levels,analyze soil moisture distribution uniformity coefficient and tomato growth at different growth stages,and major conclusions are as follows.(1)Under the conditions of different irrigation uniformity coefficient,the average value of the soil moisture uniformity coefficient is higher than 85% over the entire growth period.Irrigation uniformity coefficient has the greatest weight impact on soil moisture uniformitycoefficient.There was a linear relationship between the mean values of irrigation volume,irrigation uniformity coefficient,initial soil moisture content and soil water evenness.(2)When the initial soil moisture content of the soil is about 60%,the irrigation water amount is less than 15 mm,the initial soil moisture content and irrigation uniformity coefficient interactions had significant effect on soil moisture uniformity coefficient(P<0.05),and they are linear relationship,in other condition was not significant(P>0.05).(3)When the irrigation water for 10mm~50mm,irrigation uniformity coefficienst had no significant effect of tomato plant height,yield and irrigation water use efficiency(P>0.05),the influence of irrigation water yield reached significant level(P<0.05),and has a significant effect on irrigation water use efficiency(P <0.01).(4)Considering the tomato yield and tomato quality,chose the irrigation uniformity coefficient was 75% and the irrigation amount was 220 mm.Therefore,considering the economic efficiency and the reliability of the system,the initial water content of the soil can be increased by a small number of multiple irrigations,and the uniformity coefficient of irrigation can be reduced to 75% even 65%. |
PDF Full Text Request