PAA对土壤水肥保持作用的研究

Effects of PAA on fertilizer and water conservation of soil

在旱地赤红壤上以小白菜(Brassica chinensis L.)为供试作物,分别以水和不同pH值、质量分数为0.02％的聚丙烯酸钠(Polymer acrylic acid,PAA)稀凝胶进行灌水处理,以研究PAA对土壤水肥的保持作用。结果表明,PAA能显著降低氮素淋失量,将更多的肥料养分保留在土壤中,同时又能减少土面蒸发对土壤水分的无效消耗,从而提高水肥的利用率,最终提高小白菜的生物量。在PAA各种处理中,以pH6.5、质量分数为0.02％的PAA稀凝胶与自来水交替灌溉对水肥保持效果最好,在试验条件下,可使氮素淋失量减少72.0％,水分利用率提高23.27％,作物产量增加33.20％。

Pot experiment was carried out to study the effects of PAA on fertilizer and water conservation of soil, using dry land latosol red soil and Chinese cabbage (Brassica chinensis L) as the tested soil and crop, irrigating with water and 0.02% PAA gel of different pH value respectively. The results showed that PAA could obviously reduce N leaching loss and retain more N in the soil. Furthermore, the evaporation from soil surface was cut down, and the water use efficiency (WUE) and biomass were increased. Among the treatments, irrigation alternately with 0.02%, pH 6.5 PAA gel and water was the best, which could decrease nitrogen leaching loss by 72.00% and increase WUE and biomass by 23.27% and 33.20% respectively under experiment conditions.