Comparison of soil microbial biomass C, N and P between natural secondary forests and Larix olgensis plantations under temperate climate

摘要

Conversion of natural secondary forests (NSF) to mono-cultural Larix olgensis plantations (LOP) is a common forest management driven by an increasing demand for timber. To assess the impact of conversion of NSFs to LOPs on soil microbial properties under temperate climate, the microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and microbial biomass phosphorus (MBP) were compared between NSF stands and LOP stands in Northeast China. The results indicated that the MBC, MBN and MBP were significantly lower in LOP stands than in NSF stands for both 0-15 cm and 15-30 cm soil layers. The percentage ratios of MBC, MBN, and MBP to soil organic C, total N or total P were significantly reduced in LOP stands; and they varied with time during thegrowing season significantly. The increase of microbial biomass in summer may be an important retention mechanism for conserving soil nutrients in the studied area. The above mentioned results suggest that NSF stands are better in conserving soil microbial biomass and nutrient than those of LOP stands.