title: Changes in Biomass Carbon and Soil Organic Carbon Stocks following the Conversion from a Secondary Coniferous Forest to a Pine Plantation.
abstract: The objectives of this study were to estimate changes of tree carbon (C) and soil organic carbon (SOC) stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF) in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0-1 m). The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1) with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0-0.1 m) contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded.
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China; The Pu`er Forest Eco-system Research Station, State Forestry Bureau, Kunming, China.
authors.forename: Shuaifeng
authors.initials: S
authors.lastname: Li
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China; The Pu`er Forest Eco-system Research Station, State Forestry Bureau, Kunming, China.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Su
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China; The Pu`er Forest Eco-system Research Station, State Forestry Bureau, Kunming, China.
authors.forename: Wande
authors.initials: W
authors.lastname: Liu
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China; The Pu`er Forest Eco-system Research Station, State Forestry Bureau, Kunming, China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Lang
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Huang
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China.
authors.forename: Chengxinzhuo
authors.initials: C
authors.lastname: Jia
authors.affiliation: Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China; The Pu`er Forest Eco-system Research Station, State Forestry Bureau, Kunming, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Forestry Research Institute of Pu'er Municipality, Pu'er, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Tong
mesh_terms: D018533:Biomass; D002244:Carbon / Q000737:chemistry*; D002681:China; D017753:Ecosystem; D065928:Forests; D028223:Pinus; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil; D002244:Carbon