Study on the soluble salt ions contents of Populus alba L.var.pyramidalis growing in salinity soils
不同土壤盐分条件下新疆杨可溶性盐离子含量变化的研究

The soluble salt ions contents of Populus alba L.var.pyramidalis growing in two kinds of salinity soil were studied.The results show that the soluble salt ion contents in the soil of waste canal are higher than those of irrigation canal,and there is significant difference between them except HCO~-_3 and K~ .But the differences in soluble salt ion contents are indistinctive in the parts of the trees above the ground growing at the same age in the two kinds of soil.There are obvious differences in the contents of Cl~-,Mg~(2 ),Na~ and K~ in the roots of Populus alba L. var.pyramidalis.These demonstrate that the tree has certain repellent function to higher salt ions in the soil. Populus alba L.var.pyramidalis is able to control Cl~- and Na~ that bring poison to the tree in the roots and restricts them from getting into leaves,branch and trunk.The roots have strong selective absorbability to SO_4~(2-) and Ca~(2 ) and can remove surplus SO_4~(2-) and Ca~(2 )out of the body.The roots of the tree have weak selective absorbability to Cl~- ,Mg~(2 ) and Na~ .