根层铺多孔膜对和田风沙土水分入渗及蒸发的影响研究

Effects of porous film mulching in root zone on water infiltration and evaporation of Hetian aeolian sandy soil

为探讨根层铺多孔膜对新疆和田风沙土水分入渗及蒸发的影响,研究中设置了3个开孔度(30%、40%和50%)和3个埋深(10、15和20 cm),以不铺多孔膜处理为对照,开展了室内的入渗及蒸发试验,研究了风沙土水分入渗及蒸发特征。结果表明:根层铺多孔膜可以有效减缓土壤水分入渗,随多孔膜埋深的增加,土壤水分入渗速率呈先减小后增大的趋势,而开孔度的增大则加快了土壤水分的入渗速率,当开孔度与埋深组合为30%与15 cm时,土壤水分入渗速率和渗漏量均最小;铺多孔膜处理中,埋深10 cm各处理的土面累积蒸发量较对照处理显著降低(P<0.05),其中开孔度40%处理的土面累积蒸发量较对照处理减少了18.67%,体现了根层铺多孔膜技术具有较好的抑制蒸发作用;累积蒸发量随着开孔度的增大先减小后增大,随多孔膜埋深的增加先增大后趋于稳定。从减缓入渗和抑制蒸发的角度考虑,对于和田风沙土,适宜的铺多孔膜技术参数为开孔度40%,埋深10 cm。

In order to explore the effects of the porous film mulching in root zone(PFMRZ)on the water infiltration and evaporation of Hetian aeolian sandy soil,three porosity openings(30%,40%and 50%)and three buried depth(10 cm,15 cm and 20 cm)of this film,as well as one control without film were set up for the laboratory test to study the characteristics of water infiltration and evaporation of aeolian sandy soil.The test results show that PFMRZ can effectively slow down the infiltration of soil water,with the increase of the buried depth,soil water infiltration rate decreases first and then increases,and the increase of the porosity opening speeds up the soil water infiltration rate.When the porosity opening is 30%and the buried depth is 15 cm,the soil water infiltration rate and leakage reach the minimum.Among the treatments of PFMRZ,the cumulative evaporation of the soil surface of each treatment with the buried depth of 10 cm is significantly lower than that of the control treatment(P<0.05),among which it is reduced by 18.67%compared with the control treatment when the porosity opening is 40%,demonstrating that PFMRZ performs well in suppressing evaporation.The cumulative evaporation decreases first and then increases with the increase of the porosity opening,whereas it increases first and then tends to stabilize with the increase of the buried depth of the porous film.In order to slow down infiltration and suppress evaporation,the suggested technical parameters of porous film for Hetian aeolian sandy soil are 40%porosity opening and 10 cm buried depth.