人工林代替天然林后土壤碳库的变化

Changes in soil carbon pools under Chinese fir (Cunninghamia lanceolata) and bamboo (Phyllostachys pubescent) plantations substituted for a native forest (Quercus acutissima, Cyclobalanopsis glauca, Cas-tanops~.s sclerophyUa, Platycarya strobilacea, Lithocarpus glaber) were studied on the hills with acid parent rock and soils classified as red soils (Ferrisols) in Huzhou, Zhejiang Province of east China. It was found that total soil organic carbon (TSOC), easily oxidisable carbon (EOC) and water-soluble organic carbon(WSOC) under bamboo plantation were increased, but microbial biomass carbon (MBC) was decreased. On the contrary, Chinese fir induced declines of all fractions of C including TSOC, EOC, WSOC and MBC.The percentages of the active fractions of soil C (EOC and WSOC) were increased in the plantations as compared to the native broad-leaved forest, but proportions of soil organic C as MBC were decreased. It could be concluded that bamboo plantation had a great ability of not only fixing C but also accelerating soil C pool cycle, improving nutrient and microorganism activity; therefore, it is a good ecosystem and could be recommended for wide development. Chinese fir would shrink the soil C pool and deteriorate sou biological fertility, so it did not benefit CO2 fixing and land sustainable utilization.

Changes in soil carbon pools induced by substitution of plantation for native forest

Changes in soil carbon pools under Chinese fir (Cunninghamia lanceolata) and bamboo (Phyllostachyspubescens) plantations substituted for a native forest ( Quereus acutissima, Cyclobalanopsis glauca, Cas-tanopsis sclerophylla, Platycarya strobilacea, Lithocarpus glaber) were studied on the hills with acid parentrock and soils classified as red soils (Ferrisols) in Huzhou, Zhejiang Province of east China. It was foundthat total soil organic carbon (TSOC), easily oxidisable carbon (EOC) and water-soluble organic carbon(WSOC) under bamboo plantation were increased, but microbial biomass carbon (MBC) was decreased. Onthe contrary, Chinese fir induced declines of all fractions of C including TSOC, EOC, WSOC and MBC.The percentages of the active fractions of soil C (EOC and WSOC) were increased in the plantations ascompared to the native broad-leaved forest, but proportions of soil organic C as MBC were decreased. Itcould be concluded that bamboo plantation had a great ability of not only fixing C but also accelerating soilC pool cycle, improving nutrient and microorganism activity; therefore, it is a good ecosystem and could berecommended for wide development. Chinese fir would shrink the soil C pool and deteriorate soil biologicalfertility, so it did not benefit CO2 fixing and land sustainable utilization.