蓄淡养鱼改良江苏滨海强度盐渍化土壤的探讨

RESULTS OF RECLAMATION OF MARINE HIGHLY-SALINE SOILS UNDER DIFFERENT AMELIORATION WAYS

在江苏大丰滨海强度盐渍化土壤上采用围田蓄淡养鱼改土、垦荒旱作、抛荒自然淋洗3种方法,探讨了对江苏沿海强度盐渍化土壤的改良效果.1.围田蓄淡养鱼2年的土壤脱盐率最高,为旱作的2倍,为抛荒法的4倍以上;0～20cm 土层钠吸附比(SAR)亦以蓄淡养鱼法下降最快,旱作次之,抛荒法几无变化;在土壤剖面上,3种改良途径的钠吸附比均呈倒“T”型;在0～20cm 土层,Na^+/Ca^(2+)变化趋势同SAR,在土壤剖面上,Na^+/Ca^(2+)变化除抛荒法不明显外,其它两改良途径同 SAR 在土壤剖面上变化趋势一致.2.有机质增加以蓄淡养鱼最为显著,旱作次之,抛荒无明显变化;无论何种途径,表土腐殖质结构均简单,胡敏酸/富里酸(H/F)均较窄;土壤脲酶及碱性磷酸酶的活性均以蓄淡养鱼最高.

The present paper deals with the results of reclamation of marine highly-saline soil in threedifferent amelioration ways,e.g,accumulation of fresh water in enclosed land in which fish was raised(Water logged),reclaiming cultivation in dry land(Dry land)and CK.1.The rate of Salt decrease in Waterlogged was twice that in Dry land,and 4 times that in CK.2.The increase of organic matter was most signif-icant in Water logged soils,then in Dry land,but no significant increase of organic matter occured in CK.The humus structures in all treatment surface soils were simpler and H/F narrower.The activities of ureaseand alkline phosphatase in Water logged soils were highest of the all treatment soils.