Analysis Of Properties Of Super Absorbent Polymer And It's Application Effect On Carrot In Sandy Soil In Semiarid Area

At present, with the situation of the shortage of water resources is become stern day by day, under the situation of limited water volume, how to enhance the water use efficiency as far as possible is become a hot topic in domestic and foreign countries. Super absorbent polymer technology is the developed rapidly agricultural chemical water-saving techniques in recent years.This thesis through laboratory and field experiments, study the absorption and water retention of SAP, and the effect of SAP on carrot's emergence,growth,yield and the soil moisture content and so on, to maintain the theoretical support and technical guidance of super absorbent polymer application in water-saving agriculture.The mainly results are as follows:In the running water, the absorption ratio of SAP is mainly affected by the texture characteristic of SAP, the maximum absorption ratio of SAPs that have different ingredient are different obviously;the pellet size of SAP affects its water absorbing speed, the water absorbing speed of SAP that the particle size is thin is quick, the water absorbing speed is slow if the SAP's particle size is thick。The absorption ratio of SAP in solution that includes Ca2+ and Na+ was decreased remarkably compared with in the running water, and the effect of divalent ion on water absorption of SAP is big than the one price ion. The water retention of soil is enhanced obviously after SAP was added into the soil, and the effect in the soil that sand content is high is best, but the quantity of SAP should not to be too much, when the amount of SAP is more, the soil wither coefficient increase obviously. The soil properties has important effect on water absorption and retention of SAP. the water absorption ratio of SAP is lower in the soil that its clay percent is higher than in the soil which its clay content is lower. but the water retention is exactly opposite.The right amount of SAP has obvious function for enhance the soil water content, but, for 0~20cm upper layer, the soil water content is not enhanced obviously when the furrow fertilization quantity of SAP is more. Because of the enhancing of water content, promoting the emerge of carrot and growth, then enhance the yield, but its application effect is affected by the application quantity,application way of SAP and the soil moisture content and so on. Considering the application effect and economy, for soaking seeds and furrow fertilization of SAP , the suitable quantity of SAP is 0.4 to 0.5 and 1.5 to 2.0 kilogram per acre respectively; For the treatment which SAP is mixed with soil, under the condition that the total quantity of rainfall is 154mm and the amount of irrigation water is about 450m3 per acre in the period of duration, it has no obvious function for enhance the emerge rate and yield when the quantity of SAP is between 1.0 to 3.0 kilogram per acre. After the SAP is added into soil, the emerge rate of carrot does not have obvious decrease if reduce the seed amount suitably. The effect of SAP on carrot's emerge rate is also affected by the application depth of SAP, for furrow fertilization, when the density is low, the emerge rate that the application depth of SAP is shallow is higher than that the depth is deep, when the density is high, the emerge rate that the application depth of SAP is deep is higher than the depth is shallow, but, whether the depth is deep or shallow, the emerge rate is decreased comparing the control that without SAP when the density of SAP surpass 0.50%. When application depth and application quantity of SAP are same, the emerge rate that SAP is mixed with soil is higher than the furrow fertilization when the density is low, although the carrot's emerge rate of furrow fertilization is higher than that the SAP is mixed with soil when the density is high, the carrot's emerge rate of two different ways has no obvious difference. The SAP also has obvious function for enhance the carrot's economic efficiency. for soaking seeds and furrow fertilization of SAP, when the SAP application quantity is 0.4 kilogram and 2.0 kilogram per acre respectively, for the two different ways, the carrot's additionally receives per acre may reach 488.5 and 344.6 Yuan. respectively.