不同栽培年限大棚土壤盐分变化特性研究

Study on Salinity Change of Different Planting Age Greenhouse Soil in Yangling Area

[目的]为了探明杨凌大棚土壤次生盐渍化的演变特性。[方法]以露天菜地为对照,运用相关及方差分析方法,研究了杨凌地区不同种植年限的大棚土壤水溶性盐分的变化特性。[结果]大棚土壤中水溶性总盐含量与电导率(EC)比露地蔬菜土壤明显增高,且随栽培年限的延长总盐含量与EC值逐渐升高,水溶性总盐与EC值在0-10cm土层呈线性正相关,R2=0.9106。对不同棚龄土壤总盐含量进行方差分析可知,F=16.977>F0.01=5.06,3、5年大棚土壤含盐量与其他处理之间有显著差异,3年大棚土壤与其他处理有极显著差异。随着栽培年限的延长,土壤pH值呈逐渐下降的趋势,在0-40cm土层,大棚土壤pH值随土壤层次加深而增高。8大离子组成中阴离子以SO42-为主,阳离子以Ca2+为主,分别占总盐的24.42%和21.46%。大棚土壤盐渍化趋势随栽培年限的延长越来越明显。[结论]确定了杨凌地区土壤盐渍化的演变规律,为解决设施农业发展中存在的土壤障碍问题提供了理论支持。

[Objective] The aim was to study the evolutional characteristics of the soil salinization in greenhouse. [Method] Taking open -air vegetable soil as CK, the physical and chemical characteristics of water-soluble salt in different regions and different planting age in Yangling were analyzed by using variance and correlation analysis methods. [Result] The results showed that the content of water-soluble salt and EC value in greenhouse soil was significantly higher than in the open field, and the content of total salt and EC value increased gradually with extended of planting age. The content of total water-soluble salts and the EC value also showed linear correlation in 0-10 cm soil layer between, R^2 = 0.910 6. By analysis of variance, F= 16.977 〉F001= 5.06. The content of water-soluble salts of 3, 5 years greenhouse soil treatments were significantly difference from the others, and which of 3 years greenhouse soil treatment was much significantly difference from the others.The pH value decreased slightly with extended of planting age. With the soll layers deep, greenhouse soil pH value gradually increased in 0-40cm soil. In the salt composition, cation mainly was Ca^2＋ , anionic mainly was SO4^2-. The tendency of salinization of greenhouse soil was getting more and more obvious with the cultivation age. [Conclusion] The study found the change law of the soil salinization in Yangling area, which offered the theoretic sustainment for solving soil obstacle in facility agriculture development.