接种AM真菌对PAEs污染土壤中微生物和酶活性的影响

Effect of inoculation with AM fungi on microorganism and enzyme activity in PAEs-polluted soil

土壤灭菌条件下 ,添加 5 0mg·kg-1DEHP和 5 0mg·kg-1DBP ,在温室进行盆栽试验 ,观察土壤施加DEHP与DBP和接种AM真菌 (Acaulosporalavis,光壁无梗球囊霉 ,菌号 :34)后菌根际 (简称A)、菌丝际 (简称B)和常规土 (简称C)中土壤微生物和部分土壤酶活性的变化。结果表明 ,土壤施加DEHP和DBP后 ,A、B和C层土中土壤微生物数量和土壤酶含量下降 ;接种AM真菌后 ,受AM直接影响的A和B层土中细菌、放线菌和真菌数量比不接种低 ,而C层土中三菌数量比不接种高 ;A和B层土中中性磷酸酶和脲酶含量下降 ,脱氢酶含量在A、C层土中下降 ,在B层土中稍有增加 ,AM对土壤脱氢酶活性影响不大。

In greenhouse, a pot experiment was carried out to study effects of application with 50 mg·kg -1 DEHP and 50 mg·kg -1 DBP and inoculation with Acaulospora lavis(strain No. 34) on microorganism numbers and enzymes activity in the mycorrhizosphere(A), hyphosphere(B) and bulk soil(C) of sterilized soil, respectively. The results indicated that compared with no DEHP and DBP (CK), microorganism numbers and enzymes concentration in the A, B and C soil layer respectively decreased after application with DEHP and DBP. After inoculation with AM fungi, the numbers of bacteria, fungi and actinomycetes in the A and B soil layer were lower than those in the uninoculated treatment. But they were higher in C soil layer than those in the uninoculated treatment. Compared with uninoculated treatment, neutral phosphatase and urease concentration decreased in the A and B soil layer inoculated with AM fungi, but dehydrogenase concentration slightly increased in the B soil layer and decreased in the A and C soil layer. AM slightly affected dehydrogenase activity. It suggested that DEHP and DBP could destroy microorganism and enzyme in soil, and inoculation with AM fungi did not decrease those harmful effects.