Native bamboo invasions into subtropical forests alter microbial communities in litter and soil

Abstract

Both exotic and native plant invasions can have profound impacts on ecosystems. While many studies have examined the effects of exotic plant invasions on soil properties, relatively few have tested the effects of native plant invasions on soil microbial communities. Furthermore, we know little about the effects of native plant invasions on microbial communities in litter. In subtropical forests in southern China, we sampled litter at three decomposition stages and top soil in three forest sands representing three stages of the invasion (not invaded, moderately and heavily invaded) by the Moso bamboo (Phyllostachys edulis (Carriere) J. Houzeau), a native species in China. We measured chemical properties (concentrations of C, N, P, Mg, Al, K, Ca, Mn, Cu, and Zn, and concentrations of cellulose and lignin) and microbial communities in litter and/or soil. The bamboo invasion, in general, decreased the element concentrations in litter and soil and also decreased total microbial abundance and diversity. Considering bacteria and fungi separately, the bamboo invasion decreased fungal diversity in litter and soil, but had little impact on bacterial diversity, suggesting that fungi are more sensitive and vulnerable to the bamboo invasion than bacteria. We conclude that native Moso bamboo invasions into subtropical forests may lead to a complex biogeochemical process in the litter-soil system, which may threaten local forest ecosystems by affecting microbial communities and, thus, litter decomposition and nutrient cycling.