Abstract:

Surface soil (0-20 cm) samples were collected in 2006 from five moso bamboo (Phyllostachys edulis) plantations which were respectively planted in 2002, 1996, 1990, 1980 and 1960 and extensively managed. Dynamics of the soil microbial biomass and diversity with cultivation time of the bamboo plantations were investigated by means of phospholipid fatty acids (PLFAs) analysis. A site of Pinus massoniana (PM) forest nearby with the similar ecological background was selected as a reference. It was found that the average microbial biomass and diversity were lower (P<0.05) in the soil of the bamboo forest planted in 2002 than in that in the natural PM forest, that is, both species numbers and populations of the soil microbes declined in a short term after PM being transformed into bamboo forest. Afterwards, a gradual recovery tendency of microbial biomass and species was observed with increasing cultivation time of the bamboo plantations, and soil average microbial biomass and diversity in 25- and 45-years-old bamboo plantations (respectively planted in 1980 and 1960) were similar with (P<0.05) that in natural PM forest. Statistical analysis of PLFAs data showed that the composition of soil microbial communities in PM forest was obviously different from those in bamboo plantations, and the dissimilarity increased with time of bamboo cultivation. It was concluded that in comparison with PM, long-term extensive management of bamboo plantations did not bring about significant change in soil microbial biomass and diversity, but microbial communities varied with the increasing time of bamboo plantation, indicting bamboo plantation ecosystem under extensive management could develop rich biodiversity and be sustainably developed.

Key words: Phyllostachys edulis plantation, cultivation history, soil, phospholipid fatty acid (PLFA), microbial community structure