供水厂排泥对土壤固磷及理化特性的影响研究

进行了城市供水厂排泥施用于花园土壤的试验研究。单因素对照试验结果表明,土壤施用污泥后,其渗流出水中溶解磷量降低,土壤的固磷作用增强。当污泥施加量为60t/hm2时,和对照组相比,渗流液中溶解磷浓度、土壤容重分别降低了37.3%和22.9%,含水率和孔隙率较对照组分别增加了81.7%和11.0%。正交试验得出了渗流液含磷量、土壤容重等考察因素与河沙、污泥施加量关系的一次回归方程。在同一时段,土壤含水率、土壤孔隙率与河沙、给水污泥施加量呈正相关,土壤容重与土壤性质以及给水污泥加入量呈负影响,并不同程度存在交互效应。给水污泥适度施用于土壤,对其结构与理化性质的改善明显。

Impact of waterworks sludge on phosphorus-fixation and phy-Chemical properties of Soil

Experiment of city waterworks sludge used for garden soil was studied,the results of the single-factor comparison test showed that,after applying the sludge,the phosphorus in seepage water out of the soil decreased,the effect of the soil on phosphorus-fixation was enhanced.When the amount of applied sludge was 60 t/hm2,compared with the control group,the concentration of dissolved phosphorus in the seepage water and the soil volume weight of the test group decreased by 37.3% and 22.9% respectively,meanwhile,the moisture content and the soil porosity increased by 81.7% and 11.0% respectively.Through the orthogonal test,a liner regression equation which describe the relationship between some investigating factors such as phosphorus content of the seepage water,soil volume weight and the amount of the applied river sand and sludge was deduced.It was indicated that,during the same period of time,soil moisture content and porosity had positive correlation with amount of applied river sand and sludge,however,soil volume weight had negative effect on soil characteristics and amount of applied waterworks sludge,besides,reciprocal effects appear in different degrees.It was proved that soil constructer and phy-chemical characteristics were very improved when waterworks sludge was properly used.