外源植物碳输入对城市土壤微生物群落结构的影响

By using phospholipid fatty acid（PLFA）method, on the conditions of extracellular plant carbon added，the discriminative features of soil microbial community structure between Psidium guajava Linn and Zoysia matrella lawns were studied.The results showed that extracellular plant carbon added significantly improved all kinds of microbial content in Psidium guajava Linn．In Zoysia matrella lawns，extracellular plant carbon added had no significant effect on the total microbial content，and the bacterial content decreased significantly，the other kinds of microbial content tended to decrease unsignificantly. Exogenous plant carbon added made the proportion of Gram-positive bacteria and Gram-negative bacteria decreased and the proportion of Fungi and bacteria increased．Analyzing variation of microbial community structure between Psidium guajava Linn and Zoysia matrella lawns showed that the Shannon's diversity index，Pielou's evenness index，and Simpson's dominance index were not influenced by extracellular plant carbon added．In conclusion，when facing nonnative human disturbance，microbial community structure between Psidium guajava Linn and Zoysia matrella lawns has better self-adjustment ability and is conducive to a stable city ecosystem．