Changes in soil microbial community structure and metabolic activity following conversion from native Pinus massoniana plantations to exotic Eucalyptus plantations
Journal
Forest Ecology and Management
Journal Volume
291
Pages
65-72
Date Issued
2013
Author(s)
Abstract
Afforestation after deforestation using fast growing exotic species is creating major land use changes throughout China and the world. However, few studies have looked at changes in soil microbial communities resulting from the planting of exotic species. With paired comparison design, we studied the effects of replacing a native Pinus massoniana plantation with an exotic Eucalyptus (Eucalyptus urophylla×grandis) plantation on the composition and carbon metabolic function of soil microbial communities in Guangxi Province, southern China. We compared the microbial biomass, phospholipid fatty acid (PLFA) composition and carbon metabolic function (BIOLOG profiles) between both plantation types. Results showed the abundance of bacterial, fungal, actinomycetal, and total phospholipid fatty acids, and the proportion of 16:1ω5c and five gram-negative characteristic bacterial PLFAs (of the six detected) in the Eucalyptus plantation soils were significantly lower than those of the P. massoniana plantations, as were biomass, carbon metabolic activity, and richness and diversity of the soil microbial community. The indicators denoting stress related to soil nutrient levels were significantly higher in the Eucalyptus plantation soils, such as the ratios of monounsaturated to saturated fatty acid, gram+ to gram- bacteria, iso- to anteiso-branched PLFA, and cy19:0 to 18:1ω7c. Canonical correspondence analysis (CCA) indicated the significant changes in the soil microbial community were mainly due to shrub and herb coverage, soil water content, soil organic carbon, soil N:P, and available N. Our research suggests forest conversion from native P. massoniana plantations to exotic Eucalyptus plantations alters the structure and function of the soil microbial community driven mainly by shifts in understory coverage and soil resource availability. Improved management practices, such as litter retention, reducing soil or understory disturbance during logging and subsequent establishment of the next rotation plantation, should be considered to help improve the metabolic function of soil microbial communities and increase soil resource availability during plantation management. © 2012 Elsevier B.V.
SDGs
Type
journal article