连续四年施用规模化猪场猪粪温室土壤重金属积累研究

Accumulation of heavy metals in the four years' continual swine manure-applied greenhouse soils

分别采集连续施用0～4年猪粪的蔬菜温室土壤和蔬菜果实样品,测定土壤和果实中Cu、Zn、Pb、M n、Cr、Cd、Ni和As全量以及土壤中Cu、Zn、Pb、Mn、Cd和As有效态含量,对测定数据进行了Fisher小样本非参数随机化显著水平检验,研究连续4年施用规模化猪场猪粪的温室土壤重金属积累、重金属有效态含量变化及对蔬菜可食部分的影响。结果表明,连续4年施用猪粪,主要导致土壤中Cu和Zn的积累,As有一定积累,Pb、Cd、N i和Cr短期积累效应不明显,Mn积累不明显,长期大量施用猪粪,Pb、Cd、N i和Cr有积累的风险;土壤pH值降低;Cu、Zn有效态与全量呈显著正相关（p〈0.05）,与pH值呈极显著负相关（p〈0.01）;Pb、Cd和M n有效态与pH值呈显著负相关（p〈0.05）;Cu、Zn、Pb、Cd和M n有效态含量增加;有效态A s与全A s含量和pH值相关性不明显,但连年施用猪粪As有效态含量增加;连续4年施用规模化猪场猪粪的温室生产的部分番茄和黄瓜As含量超标。若连续以150 m^3/（hm^2·a）的猪粪施用量于该研究区蔬菜温室,土壤中全Cu和全Zn含量分别经过10年和15年可能超过国家农田土壤二级标准。该研究可为降低温室土壤重金属污染风险提供依据。

Greenhouse soils which were applied with swine manure for 0-4 years respectively and where vegetable samples were collected in a vegetable base. The total concentrations of Cu, Zn, Pb, Mn, Cr, Cd, Ni and As in soils and vegetable samples and the bioavailability concentrations of Cu, Zn, Pb, Mn, Cd and As in soils were measured, respectively. The measured data were tested using Fisher small sample non-parameter randomization. The aim was to study accumulation and bioavailability concentration changes of heavy metals in the four years continual swine manure-applied greenhouse soils and the impact of heavy metals on vegetable. Results show that after four years＇ continual swine manure applied in soils, Cu and Zn could be accumulated in soil, and As could be accumulated to some degree, and Pb, Cd, Ni and Cr were not accumulated in the short-term, Mn was not accumulated obviously, but Pb, Cd, Ni and Cr could be accumulated in soils if long-term and large quantity swine manure was applied. The pH value of the soil would decrease. The bioavailability concentrations of Cu, Zn were increased and had positive relation with the total concentrations of Cu, Zn （p 〈 0.05） and negative relation with pH value （p〈0.01）, respectively, and Pb, Mn and Cd in soil were increased and had negative relation with pH value （p 〈 0. 05）, and the bioavailability concentration of As which was not related to pH value （p 〈 0. 05） was increased too. The contents of As in some tomato and cucumber samples which were collected in four years continual swine manure applied soils exceeded the concerned standard. The total concentrations of Cu and Zn in soils could exceed the second rank of the national farmland soil environmental standard after 10 and 15 years continual swine manure-applied with the 150 m^3/（hm^2·a） quantity, respectively.