土施污泥对小麦生长的影响研究

The Effects of Applying Sewage Sludge to Manural Loess Soil on Wheat Growth

土施污泥对小麦干物质增重为１６．２％～７４．２％。污泥施量＜２％土重时，对小麦苗期生长无任何不良影响，植株茎叶中Ｃｕ，Ｐｂ，Ｃｄ含量均与对照相近，Ｚｎ，Ｎｉ略高于对照，但亦在正常范围之内；污泥施量＞２％土重时，小麦地上部分虽然生长正常，但根系生长受到明显抑制，植株体内重金属含量明显增加，其分布为根系＞茎叶。Ｚｎ、Ｃｕ在茎叶中累积能力较强，Ｐｂ，Ｎｉ主要聚积在根系里。土施污泥量以２％土重（折合４５ｔ／ｈｍ￣２）生物效应最佳。

The application of semage sludge to manural loess soil increased Wheatdry matter by 16.2%～74.2%. When the amounts of sewage sludge applied were lessthan 2%,no negative results were found to wheat seedlings,and the contents of Cu,Pband Cd in wheat shoots Were close to those in the control.Although the contents of Znand Ni were slightly higher than those in the control ,they were still in a normal range.However,when the amounts of sewage sludge used were more than 2%,the root growthwas significantly inhibited though the upper parts of wheat above the ground grew nor-mally,and the contents of heavy metal were markedly increased in plants,whose distri-bution was higher in roots than in shoots as a whole. Comparatively,Zn and Cd were ac-cumulated more in shoots while Pb and Ni in roots. Application of 2%of sewage sludge(to be converted into 45 tons per hectare)is proposed to the Lou soil,the bio-effects arethe best.