Effects of understory removal on soil microbial community composition in subtropical Phyllostachys edulis plantations

Abstract

We investigated the effects of understory removal on soil microbial community and soil physicochemical properties in a field experiment following random block design in subtropical moso bamboo (Phyllostachys edulis) plantations, which were widely contributed in middle subtropical area, aiming to assess the regulation mechanism of understory plants on soil microbial community. The results showed that understory removal significantly increased the contents of soil N, NO3--N, and soil available phosphorus, but decreased soil pH and the contents of soil NH4+-N and soil phosphorus (TP). Moreover, understory removal decreased total and bacterial PLFAs (B) and increasing soil fungal PLFAs (F), resulting in a higher F/B ratio. Redundancy analysis showed that changes in fungal PLFAs caused by understory removal were mainly attributed to soil acidification, while changes in bacterial PLFAs caused by understory removal were mainly due to the decreases in soil TP and pH. Furthermore, i14:0、i15:0 and i16:0 contributed to the decreases in bacterial biomass. Our results suggested that understory removal might not be suitable for the management of subtropical P. edulis plantations, as it would alter microbial community composition. The shift of soil microbial community from bacteria to fungi could inhibit microbial decomposition function.