长期施用粪肥对农田土壤中细菌四环素抗性水平的影响

目的]考查集约化养殖产生的畜禽粪便直接施入农田造成的环境风险。方法]以长期施用化肥的土壤为对照,通过小区定点试验,研究长期施用新鲜鸡粪、新鲜猪粪后对土壤中四环素抗性细菌的影响。结果]新鲜鸡粪、猪粪中四环素抗性细菌的数量及其占可培养细菌总数比例均远远高于施肥前的基础土样。长期施用粪肥后,土壤中四环素抗性菌数量及其占可培养细菌总数比对照均有明显增加,而且有随土壤深度的增加(0～20 cm)呈纵向增加的趋势。结论]长期施用畜禽粪肥导致土壤中微生物抗生素抗性水平大幅增加,对环境造成了一定的潜在风险。

Effects of Long-term Application of Manure on Bacteria Resistance Level to Tetracycline in Farmland Soil

Objective] The purpose of the research was to investigate the environment risk of spreading the livestock and poultry manure produced by intensive culture into farmland directly.Method] With the soil applied chemical fertilizer for a long time as CK,the effects of long-term application of fresh chicken and pig manures on the tetracycline resistance bacteria in soil was studied through fixed-plot test.Result] The amount of tetracycline resistance bacteria and its proportion accounting for the total amount of cultured bacteria in fresh chicken and pig manure were greatly higher than that in the basic soil sample before manure application.And after long-term application of these manure the amount and its proportion accounting for the total amount of cultured bacteria in soil were significantly higher than that in CK and this increase trended to vertical increment with the soil depth of 0-20 cm.Conclusion] Long-term application of manure could lead the resistance level of the antibiotic antibiotics to increase greatly,which caused a potential risk to environment.