Effect of three-ring pressure and unequal irrigation on salt content of root moist body of Lyceum Barbarum
Aiming at the problems of scarce precipitation,high evaporation,continuous spread of soil salinization area,and high water consumption in improved saline-alkali land in Xinjiang,a 3-ring irri-gation mode with lagged dripping centered on the crop was proposed to investigate its water-saving and salt-drainage effect.Taking Lycium Barbarum as the research object,according to the salt transport law within the soil wetting body,the test determines that the radius of the 1st ring,the 2nd ring and the 3rd ring were 5,10 and 15 cm,respectively.Under the condition of dripper flow rate of 3 L/h,the 1st ring(the innermost loop)started dripping first.After 2 h,when the desalination ranges of the soil wet-ting body produced by the dripping exceeded the position of the 2nd loop,then the drip valve of the 2nd loop was opened.By analogy,after 2 h,the third loop drip valve was opened,and each loop lag drip would root development range of salts gradually chase pressure to the root development to outside the range,thereby achieving the effect of water-saving and salt discharge.The profile method was used to sample and measure the salt content at different positions of the soil after drying.The results show that there is less salt near the loop center,and the farther away from the loop center the higher the salt content.Soil samples are taken at different depths of 40 cm in the horizontal direction of the center of the ring to test the salt mass ratio:61.550,57.640,53.470,50.690,and 129.650 g/kg are taken at(0,10],(10,20],(20,30],(30,40],and(40,50]cm,respectively,which indicate that soil salts accumulate at the edge of the wetted body and the effect of salt exclusion is good.At the same time,the irrigation quota of this experiment is 31.5 mm(315 m3/hm2),and the total annual irrigation water volume is 1 890 m3/hm2,which is higher than that of the conventional drip irrigation conditions.The annual irrigation volume of Lycium Barbarum is 3 450 m3/hm2,saving 1 560 m3/hm2,and the water-saving effect is remarkable.
three-ring chases pressure unequal irrigationsoil moisture bodyrebound footprint of saltsize of ringautomation
万方数据
维普
