施用城市污泥对杨树土壤化学特性及金属含量的影响

采用温室盆栽方法,研究城市污泥对杨树土壤化学特性、金属含量的影响。实验设置6个处理：4个不同用量的污泥处理：30（S1）、60（S2）、90（S3）和120 t.hm-2（S4）,以及对照（Control：不施加污泥和肥料）和无机复合肥处理（F：1.5 t.hm-2）。结果表明,施用污泥后,土壤有机质、全氮及全磷均提高,且随污泥施用量的增加而增加。S1~S4处理的土壤有机质、全氮及全磷较Control处理分别提高了32.50%~52.05%、32.00%~95.30%及75.43%~236.25%;较F处理分别提高了47.60%~69.37%、35.04%~99.70%及77.10%~239.46%。但污泥施用降低土壤pH和全钾质量分数,土壤pH较Control和F处理分别下降了0.11~0.42和0.01~0.32,但仍呈弱碱性;土壤全钾质量分数较Control和F处理分别降低了1.65%~21.51%和1.19%~21.14%。随污泥施用量的增加,土壤Cu、Zn、Ca和Na质量分数呈增加趋势,而Mn、Fe、Al、Mg质量分数呈降低趋势,其中Cu和Zn增加明显,并较Control处理分别增加了31.89%~104.36%和38.93%~358.02%,较F处理分别增加了23.10%~90.75%和37.88%~354.55%。总体而言,污泥施用于杨树后,可明显改善土壤的化学特性,但污泥施用量越大,土壤重金属Cu和Zn的质量分数残留越多。

Effects of municipal sewage sludge applications on chemical properties and metal contents in poplar soil

An experiment using pots in greenhouse was conducted to study the effects of municipal sewage sludge（MSS） on soil chemical properties and metal contents in the soil with the poplar seedlings（Populus×euramericana＇Guariento＇）.We made six treatments,i.e.,four different dosage MSS as follows： 30 t·hm-2（LS）,60 t·hm-2（MS）,90 t·hm-2（HS）,120 t·hm-2（SS）,and inorganic compound fertilizer 1.5t·hm-2（F） and Control（no application of sewage sludge and inorganic fertilizer）.The results showed that the soil organic matter,total nitrogen,and total phosphorus contents increased with the increase of MSS dosage.Treatments S1~S4 led to increases in the soil organic matter,total nitrogen,and total phosphorus contents by 32.50%-52.05%,32.00%-95.30%,and 75.43%-236.25%,respectively,compared with Control;and by 47.60%-69.37%,35.04%-99.70%,and 77.10%-239.46%,respectively,compared with F treatment.The application of MSS caused decrease in the soil pH and total potassium content,with the soil pH being 0.11-0.42 and 0.01-0.32 lower than those of Control and F treatments,respectively;and the total potassium contents was decreased by 1.65%-21.51% and 1.19%-21.14%,respectively,compared with Control and F treatments.With the increase of MSS dosage,the copper,zinc,calciumand,and sodium contents were increased,but the manganese,iron,aluminium,and magnesium contents were decreased,and the copper and zinc contents were obviously increased by 31.89%-104.36%,and 38.93%-358.02%,respectively,compared with Control;and by 23.10%-90.75%,and 37.88%-354.55%,respectively,compared with F treatment.Our results indicated that the application of MSS can obviously improve soil chemical properties,but it could increase the copper and zinc contents in soil with the increase of MSS dosage.