保护地蔬菜栽培不同灌水方法对表层土壤盐分含量的影响

通过 3年连续保护地栽培蔬菜小区试验 ,对滴灌、渗灌、沟灌 3种灌水方法的土壤盐分积累状况进行了比较研究。试验后 0～ 2 0 cm土层土壤全盐含量以沟灌最高 ,渗灌次之 ,滴灌最低 ;滴灌土壤 p H下降幅度明显低于渗灌和沟灌土壤。在 0～ 2 0 cm土层内全盐含量呈幂指数形式分布 ,即地表处含量最高 ,随深度增加逐渐下降 ;而土壤 p H则随深度增加而直线上升。另外 ,土壤中可溶性盐的阴离以 NO-3 为主 ,阳离子以 Ca2 + 为主。这说明选择合理灌水方法 ,是防止土壤退化、提高保护地作物产量和质量的有效途径。

Effects of Irrigation Methods on Salt Accumulation in Topsoil in Vegetable Field Mulched with Plastic Film

Field experiments were conducted to investigate the accumulation of soluble salt in topsoil in vegetable field mulched with plastic film under three irrigation methods (infiltration irrigation, drip irrigation and furrow irrigation). The results showed that the highest value of total salt content in 0～20 cm of soil layer appeared under furrow irrigation, and the lowest value under infiltration irrigation. Compared those values investigated under drip and furrow irrigation, the soil pH decreased more significantly under infiltration irrigation. The highest values of salt content appeared in topsoil and salt content decreased rapidly with depth increase in the profile. NO - 3 and Ca 2+ were the two ions with higher contents in soil solution. It could be deducted with the experimental result that selecting a suitable irrigation method will be an effective way to prevent soil degradation and improve yield and quality of vegetable.