干撒PAM对黄绵土工程堆积体侵蚀泥沙的影响OACSTPCD

To explore the suitable amount of dry scattering PAM(polyacrylamide)to reduce the erosion sediments and maintain the stability of engineering accumulation,0.5,1.0,1.5,2.0 and 2.5 g/m2 of PAM were dry scattered on the surface of conical loess soil engineering accumulation in the loess hilly-gully region and with no PAM as the control(CK).The effects of PAM on surface runoff,erosion sediments,rill development and soil moisture of loess soil engineering accumulation were monitored under natural rainfall conditions.The results showed that the runoff,runoff frequency and runoff coefficient of different treatments decreased first and then increased with the increase of PAM dry scattering amount.The values were the lowest when the PAM dry scattering amount was at 1.0 g/m2,and were the highest when PAM dry scattering amount was at 2.5 g/m2.The erosion sediments,rill erosion sediments and rill erosion coefficient decreased with the increase of PAM dry scattering amount.When PAM dry scattered at 1.5,2.0 and 2.5 g/m2,the erosion sediments,rill erosion sediments and rill erosion coefficient were significantly lower than that of CK and PAM dry scattering amount of 0.5 and 1.0 g/m2.When PAM dry scattered at 1.0 g/m2,the soil moisture of engineering accumulation was the highest,and when PAM dry scattered at 2.5 g/m2,the soil moisture was the lowest.When PAM dry scattering amount reaches 1.5 g/m2,PAM promoted the formation of runoff,reduced the erosion sediments and rill erosion coefficient,and reduced the soil moisture of loess soil engineering accumulation.To sum up,in order to reduce the erosion sediments and maintain the stability of loess soil engineering accumulation,the dry scattering amount of PAM should be about 2.0 g/m2.