辽宁省保护地土壤盐渍化特征的研究

在进行全面生产调查的基础上,自辽宁省主要蔬菜保护地生产区采集保护地及其相邻露地大田0~20 cm和20~40 cm土层土壤样品,测定全盐含量,探讨了当地保护地土壤盐渍化程度及其成因。结果表明:(1)保护地土壤全盐含量显著高于相邻露地相应土层土壤,0~20 cm和20~40 cm土层土壤全盐含量分别是相邻露地土壤的1.5~17.0倍和1.2~11.3倍,盐分表聚现象明显;(2)保护地土壤盐渍化现象较为严重,0~20 cm土层、20~40 cm土层全盐含量超过2 g kg-1的土样分别占46%和29%,而露地大田0~20 cm和20~40 cm土层土样全盐含量均在2 g kg-1以下。(3)区域间保护地土壤盐渍化程度不同,沈阳法库、大连瓦房店、朝阳喀左和鞍山海城等地土壤盐渍化程度相对较重,沈阳新民和丹东东港土壤盐渍化程度相对较轻,其它地区保护地土壤盐渍化程度居中;(4)土壤盐渍化与改种保护地前土壤盐分含量及改作保护地后种植年限、施肥量、复种指数等因素关系密切。因此,应加强相关研究,采取措施,积极防治保护地土壤盐渍化。

The Soil Salinization Characteristics of Protected Field in Liaoning Province

Soil samples of 0-20 cm and 20-40 cm layers were collected from major production areas of protected fields in Liaoning Province,China.On the basis of comprehensive investigation,the soil total salt was determined and it was discussed that the degree and driving reasons of soil salinization of protected fields in these areas.The results indicated:(1) The salt content of protected field soil was much higher than that of open field soil in the corresponding layer.The salt contents in 0-20 cm and 20-40 cm layers of protected field soil were separately 1.5-17.0 and 1.2-11.3 times as much as that of the corresponding open field soil,and the soil total salt accumulated in the topsoil of protected field obviously.(2) The soil total salt contents of 0-20 cm and 20-40 cm layers were both over 2 g kg-1,accounting for 46% and 29% of total soil mass,respectively.While the salt contents in the corresponding layers of open field were less than 2 g kg-1.(3) The degree of soil salinization of protected field was different between production areas.Faku in Shenyang,Wafangdian in Dalian,Kazuo in Chaoyang and Haicheng in Anshan were at higher levels of soil salinization,and producing areas such as Xinmin in Shenyang and Donggang in Dandong were at lower levels of soil salinization,while the other places were at intermediate levels;(4) There was a close relationship between the degree of soil salinization and the soil salt content before they were converted into protected fields,the planting years,fertilization,multiple cropping index and so on.Therefore,we should strengthen the research and take measures to control the soil salinization of protected field actively.