Effects of PAM mixed with urea on soil evaporation
Zhang Chunqiang, Feng Hao
(1.Research Center of Soil and Water Conservation and Ecological Environment, Chinese Academy of Sciences, 712100, Yangling, Shaanxi, China;
2.University of Chinese Academy of Sciences, 100049, Beijing, China; 3.Huaihe River Commission, 233001, Bengbu, Anhui, China)
Abstract:With the purpose of understanding the effect of PAM mixed with urea, and determining the technical parameters of field application, this study investigated the effect of PAM mixed with urea on soil evaporation through soil column experiment. The results showed that:1) when PAM and urea mixture were applied within the depth of 10cm(shallow application) in the soil column, under the amount of PAM of 0%, 0.05% and 0.1%, the effect of urea on evaporation was not significant in the first 12 days, then the evaporation decreased with the increase of urea amount (0,0.1%,0.2%,0.4%), besides, at the same level of urea, the evaporation decreased with the increase of PAM amount(0%,0.05%,0.1%,0.2%). 2)When PAM and urea mixture were applied from 10cm to 20cm(deep application) in the soil column, at the same level of PAM, the evaporation at urea amount of 0% was the biggest in the four levels of urea, and at the same level of urea, the evaporation decreased with the increase of PAM amount. 3)The total soil evaporation of deep application was bigger than shallow application. Under the condition of shallow application, the daily evaporation decreased rapidly in the first 5 days, then a slow decline in volatility from 5 to 25 days, and then tended to be stable. Under the condition of deep application, the daily evaporation kept consistent grossly in the first 10 days, and then declined gradually; after 25 days, it tended to be stable. 4) In a word, both PAM and urea inhibited the soil evaporation. The inhibition effect of PAM on soil evaporation was greater than that of urea.