管理调控措施对土壤盐分分布和作物体内盐分离子吸收的作用

通过盆栽试验 ,研究了不同管理调控措施包括施肥、灌溉、应用化学改良剂对盐渍土壤盐分分布和作物体内盐分离子吸收和分布的作用机制。结果表明 ,施用化学肥料可增大土壤电导率 ;灌水量增加可降低土壤电导率 ;施用改良剂CaSO4早期可引起土壤表层电导率升高 ,但到作物生长中、后期已与不施改良剂的相近。施肥、灌溉改善了作物生长条件 ,提高了作物的抗盐害能力。灌溉总量 375mm、三天一次的灌溉方式在降低土体盐分浓度、抑制土壤碱化方面优于两天一次的灌溉方式。大麦具有将Na 截留在茎中 ,从而减少Na 对叶片伤害的功能。大麦茎和叶中的Cl-含量都高于K 和Na 含量 ,显示较多的Cl-通过根部向地上部运输。在增加植株中K 含量、降低Na 含量 ,减轻植株盐分离子胁迫方面改良剂表现出良好的调控效果

EFFECT OF REGULATORY MEASURES ON DISTRIBUTION OF SOIL SALT AND IONIC UPTAKE BY CROP

Potexperiments were conducted in greenhouse on effects of regulatory measures including fertilization, irrigation, chemical soil amendment on distribution of soil salt and ionic uptake by crop. The results showed that fertilization increased electric conductivity of the surface soil. On the whole, electric conductivity of the surface soil in the treatment with high application rate of fertilizer was higher. Irrigation decreased electric conductivity of the surface soil layer. In the treatment with soil amendment CaSO 4 electric conductivity of the surface soil layer increased at the early stage, but came back again at the middle and later stages. Fertilization and irrigation improved the growing environment for barley and enhanced its salt resistance. When the total quantity of irrigation was maintained at 375 mm, the treatment of irrigation once every three days was superior to the treatment of irrigation once every two days in reducing salt concentration and restraining soil alkalinization. Na content in barley stem was higher than that in leaves demonstrating the function of barley retaining Na in the stem thus mitigating Na damage to the leaves. Cl - content in barley's leaves and stems was higher than K and Na content, suggesting that more Cl - was transported through roots to the above ground part. Modifier showed the good result of increasing K content and decreasing Na content in crop. The soil amendment showed positive effect in increasing K uptake, decreasing Na content in the plant and alleviating stress of the plant from salt ions.