摘要
沼液对重金属有效性的影响因土壤pH的不同而存有差异。本文分别选取pH为3.62、7.23和7.85的酸、中、碱性三种土壤,施加大型猪场厌氧发酵后的沼液,研究不同用量下三种不同pH土壤中Pb、Cu和Zn有效性的变化。结果表明,沼液低用量下(1350 m^(3)/hm^(2)),三种土壤中Pb和Zn可交换态含量分别下降50.3%~78.9%和55.1%~76.0%(P<0.05),酸性和碱性土壤中Cu可交换态含量显著降低,降幅分别为87.7%和80.8%。Pb和Cu可交换态含量的下降对应二者可氧化态和残渣态含量的增加,但Zn可交换态含量下降对应其可还原态和残渣态含量的增加。相比较而言,沼液高用量下(2700 m^(3)/hm^(2)),三种土壤中Pb和Cu可交换态含量均显著增加,增幅分别为31.0%~122.2%和84.6%~101.7%。Zn的可交换态含量在酸性土壤中增加14.3%,在碱性土壤中增加46.1%。因此,沼液施用对土壤Pb、Cu和Zn有效性的影响主要取决于其用量。低量沼液施用有助于降低重金属的有效性,但高量施用会增加重金属污染风险。土壤酸碱度差异产生的影响因重金属类型不同而存在较大变化。
The effect of pig slurry on the availability of heavy metals depends on soil pH.In the present study,three soils with pH of 3.62(acidic),7.23(Neutral)and 7.85(alkaline)were used to investigate the availabilities of Pb,Cu and Zn when adding the pig slurry from anaerobic fermentation process in a large pig farm.The results showed that under low dosage of slurry(1350 m^(3)/hm^(2)),the exchangeable content of Pb and Zn in the three soils decreased by 50.3%~78.9%and 55.1%~76.0%,respectively(P<0.05).The content of exchangeable Cu in acidic and alkaline soils was significantly reduced,with a decrease of 87.7%and 80.8%,respectively.The decrease in the exchangeable Pb and Cu contents corresponded to the increase of the oxidizable and residual fractions.But for Zn,the decrease in the exchangeable fractions corresponded to the increase in the reducible and residual contents.In contrast,under the high dosage of biogas slurry(2700 m^(3)/hm^(2))the exchangeable Pb and Cu fractions in all soils increased by 31.0%~122.2%and 84.6%~101.7%,respectively.The exchangeable Zn fractions increased by 14.3%in acid soils and 46.1%in alkaline soils.Therefore,the effect of pig slurry on the availability of soil Pb,Cu and Zn mainly depends on its dosage.Low dosage of application helps reduce the availability of heavy metals while high dosage would increase the pollution risk.In the context,the impact of soil pH varies greatly among different heavy metals.
作者
韩金
范弟武
郭俨辉
申建华
韩建刚
HAN Jin;FAN Di-wu;GUO Yan-hui;SHEN Jian-hua;HAN Jian-gang(Collaborative Innovation Center of Sustainable Forestry in Southern China of Jiangsu Province,Nanjing Forestry University,Nanjing,Jiangsu 210037,China;College of Biology and the Environment,Nanjing Forestry University,Nanjing,Jiangsu 210037,China;COFCO Meat(Jiangsu)Co.,Ltd,Dongtai Jiangsu 224200,China)
出处
《农业现代化研究》
CSCD
北大核心
2021年第2期321-329,共9页
Research of Agricultural Modernization
基金
国家重点研发计划课题(2017YFC0505803)
国家自然科学基金(41977354,41471191)。
关键词
沼液
PH
重金属
形态
有效性
pig slurry
pH
heavy metals
fractions
availability
