耐铅菌与生物炭、有机肥配施对铅污染土壤的修复效果

Repair Effect of Lead-tolerant Bacteria Combined with Biochar and Organic Fertilizer on Lead-contaminated Soil

为明确耐铅菌联合生物炭、有机肥2种载体对铅污染土壤的修复效果,采用盆栽试验方法,进行了铅在油菜体内铅含量、土壤有效态铅含量以及土壤酶活性、微生物数量的响应研究。结果表明,生物炭和有机肥与不同接菌量配施均降低了油菜铅含量以及油菜对铅的转移和富集;相同基质配施条件下,随着接菌量增加,油菜铅含量先减少后增加,其中,接菌量0.5 g/kg、生物炭20 g/kg处理(T+J2)和接菌量0.5 g/kg、有机肥20 g/kg处理(F+J2)油菜地上部、地下部铅含量较少,与CK相比,2个处理地上部铅含量分别下降56.78%和30.40%,地下部铅含量分别下降22.94%和16.71%,且均达显著水平;T+J2和F+J2处理土壤有效铅含量也较低,分别较CK降低21.32%和12.61%;油菜根区土壤酶活性与微生物多样性随着接菌量的增加先增大后减小,当接菌量为0.5 g/kg时,土壤真菌、放线菌数量最多,4种酶活性也最大。耐铅菌以接菌量0.5 g/kg与生物炭、有机肥配施后对铅污染土壤修复效果最佳。

To clarify the effect of lead-tolerant bacteria combined with biochar and organic fertilizer on lead-contaminated soil,the pot experiment was used to study the content of lead in rapeseed,soil effective Pb concentration,soil enzyme activity and microbial response.The results showed that the combination of biochar and organic fertilizer and different inoculation amount decreased the lead content in rapeseed and the transfer and enrichment of lead in rapeseed.Under the conditions of the same substrate,the lead content in rapeseed decreased first and then increased with the increase of inoculum.Compared with CK,T+J2 and F+J2 treated the above ground and underground of rapeseed with the lowest lead content,the above ground lead content decreased by 56.78%,30.40%,respectively,and the underground lead content decreased by 22.94% and 16.71%,respectively,both of which reached significant levels.T+J2 and F+J2 treatment,the soil effective lead content were the lower in all processed,which were 21.32%and 12.61%lower than CK of effective Pb content,respectively.Similarly,soil enzyme activity and microbial diversity in the root zone of rapeseed increased first and then decreased with the increase of the amount of bacteria inoculated.The amount of bacteria inoculated was 0.5 g/kg,and the number of soil fungi and actinomycetes was the largest,and the four kinds of enzyme activities were the largest in all processed.Therefore,when the lead-tolerant bacteria were combined with biochar and organic fertilizer with the inoculating amount of 0.5 g/kg,the effect on the repair of lead-contaminated soil was the best.