如东棉花原种场滨海盐渍土盐渍性状变化的特点

在如东县棉花原种场大比例尺土壤调查的基础上研究了该场滨海盐渍土变化的特点。结果如下:1.土壤脱盐速度快。2.土壤脱盐自表层开始。3.潜水淡化落后于土壤脱盐。4.可溶盐中各种离子迁移能力的不同导致脱盐过程中盐分化学类型的改变。5.碱化度随钠吸附比而下降。6.脱盐过程中有碱化度下降的滞后现象。由于有以上的盐渍变化特点,所以,底层轻度盐化潮土似乎是盐渍土向潮土方向发育的必经阶段,而盐化潮土下层的碱化度仍较高,这属于残留性质,不是土壤碱化的结果。

VARIATIONS IN THE SALT AFFECTED PROPERTIES OF SEASHORE SOIL ON RUDONG COTTON RAW SEED GROWING FARM

This study is based on the large scale map of soil survey of Rudong Cotton Raw Seed Growing Farm. Results indicate.1. Desalinization process is rapid. 2. Desalinization begins from surface layer. 3. Dilution of groundwater falls behind of soil desalinization. 4. The uneven capabilities of ion-transmission lead to the variation of salt chemical compositions during desalinization process. 5. Exchange sodium percentage decreases with sodium adsorption. 6. The hyteresis of dealkalization occurs with desalinization.All the above characteristics of change result in the fact that the formation of lightly salinized alluvium soil in the bottom is the inevitable transitional stage of the transformation of alluvium soil from salt-affected one. In the meanwhile, the occurence of still higher exchange sodium percentage in the lower layer is considered of being the residual effect instead of the outcome of alkalization.