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采用野外调查和取样分析相结合的方法,对武汉市郊部分设施蔬菜栽培地土壤盐分特征进行了研究。结果表明:(1)在研究区,轻度盐化土壤占52.63%,中度盐化土壤占21.05%,重度盐化土壤占5.26%,另有15.79%的设施土壤盐分含量超过了10g/kg,达到盐土的标准。(2)设施栽培土壤的可溶性盐含量与电导率(EC)均明显高于露天栽培菜地及植棉地土壤,且变化幅度大,平均值分别为6.6g/kg和0.31mS/cm。其中,10.5%的设施土壤表层EC值达到了作物生长障碍临界点(>0.6mS/cm)。表层土壤中以NO3-和Ca2+的相对富集为主要特征。(3)盐分的运移同时存在着向下迁移和向表层聚集两种方式,且以表聚为主。除HCO3-外,其它盐分离子的含量随土层深度的增加而有所降低,其中,NO3-、Ca2+累积迁移量较大,在0～100cm各土层内的含量都高于露天菜地和植棉地,硝酸盐的大量累积和向下迁移势必对地下水造成不利影响。(4)设施地栽培的土壤水溶性盐含量与电导率(r=0.9512**)以及硝态氮含量(r=0.6442*)分别呈极显著和显著正相关。
A field investigation and sampling analysis were used to study the characteristics of soil salinity of vegetable cultivation in some facilities in the suburbs of Wuhan. The results showed as follows: (1) In the study area, mild salinization accounted for 52.63%, moderate salinization accounted for 21.05%, heavily salinized soil accounted for 5.26%, and another 15.79% of the facilities had soil salinity over 10g / kg , Reaching the standard of salt. (2) The soluble salt content and conductivity (EC) of cultivated soils were significantly higher than those of open cultivated vegetable land and cotton-paddy soils, and the variation range was large with the average values of 6.6g / kg and 0.31mS / cm. Among them, 10.5% of the soil surface EC value of the facility reached the critical point of crop growth disorder (> 0.6mS / cm). Surface soil in the NO3- and Ca2 + relative enrichment as the main feature. (3) There are two modes of salt migration: migration downward and surface accumulation. Except for HCO3-, the contents of other salt ions decreased with the increase of soil depth. Among them, the accumulation and migration of NO3- and Ca2 + were relatively large, Cotton plants, nitrate accumulation and the large amount of migration will inevitably adversely affect the groundwater. (4) Soil water-soluble salt content of cultivated soils in plantations showed extremely significant and significant positive correlation with conductivity (r = 0.9512 **) and nitrate nitrogen content (r = 0.6442 *).