---

作 者 ：余海英1;2;李廷轩1;2;周健民2

期 刊 ：植物营养与肥料学报 2007年 13卷 4期 页码：642-650

关键词：设施土壤；盐分累积；离子组成；

Keywords:greenhouse soil, salt accumulation, ion composition,

摘 要 ：通过对我国不同地区设施栽培现状的野外调查和取样分析,研究了设施栽培条件下土壤盐分的累积、迁移及离子组成变化特点。结果表明:1)设施栽培条件下,土壤含盐量的变化幅度大,且均明显高于露地土壤,各研究区域内已有40%8～9%的土壤含盐量超过了作物正常生长的临界浓度。2)设施栽培的可持续利用周期较短,连续种植到4年左右的设施土壤,其耕层盐分的累积量可达到作物的生长障碍临界点,之后因设施使用率的下降以及采取的措施而有所降低,但仍高于露地土壤。设施连续使用会导致土壤环境质量的不断恶化。3)设施土壤剖面(0—100.cm)盐分含量均高于相邻露地,盐分含量随土层深度增加而降低,其中耕层(0—20.cm)的盐分含量显著高于其下各层;盐分离子在土壤剖面的运移同时存在着明显的向底层迁移和向表层聚集两种方式,但以表聚为主;此外,盐分离子的大量累积和向底层迁移,特别是NO₃^-的淋溶已严重影响到部分地区的地下水水质。4)设施栽培后,土壤中的NO₃^-、SO₄^2-、Cl^-、Ca²⁺、Mg²⁺、K⁺、Na⁺均有不同程度的累积,阴离子以NO₃^-和SO₄^2-为主,阳离子以Ca²⁺为主。盐分的大量累积以及某些离子的相对富集在一定程度上引起了作物养分的供需失衡、土壤酸化、棚室内CO₂供应不足等生产问题。

Abstract:By investigating greenhouse cultivation in different regions of China and analyzing both greenhouse and open field soil samples,salt accumulation and translocation in greenhouse soils was studied.The results indicated that salt content in greenhouse soils was higher than that in open field soils.The salt content in 40%～89% of greenhouse soil samples reached the stunt point for vegetables.Salt accumulation is a main limiting factor for sustainable development of greenhouse cropping.The highest salt content was found in greenhouse soils used for about 4 years,when salt content might reach the threshold value limiting normal growth of crops,then it would decrease by some countermeasures but still higher than open-field soil.Compared with neighboring open field soils,the salt content of the greenhouse soil decreased with depth.Greenhouse soils displayed apparent phenomena of salt accumulation in topsoil(0-20cm) and salt leaching downwards to the bottom of the soil(80-100cm),especially NO₃^- that seriously affected the quality of groundwater in the area.Apart from HCO₃^-,the contents of NO₃^-、SO₄^2-、Cl^-、Ca²⁺、Mg²⁺、K⁺、Na⁺ were increased to different degree in greenhouse soils,and NO₃^- 、SO₄^2- and Ca²⁺ were the major ions in the soils.The large accumulation of salt and some salt ions might cause induce other limiting factors of greenhouse cropping system,such as the nutritional disorders,acidification of soil and the short supply of CO₂ etc.

---