title: [Carbon density and production in valley spruce-fir forest in Xiaoxing'an Mountains, China].
abstract: The carbon density and production were measured using both forest inventory and allometry approaches in the declining valley spruce-fir forest in Xiaoxing' an Mountains. Results showed that the total carbon density of the forest was 268. 14 t C · hm(-2) in 2011, and carbon densities of the vegetation, detritus and soil were 74.25, 16.86 and 177.03 t C · hm(-2), respectively. From 2006 to 2011, tree layer carbon density decreased from 80.86 t C · hm(-2) to 71.73 t C · hm(-2). The average decrease proportions per year of carbon density were 0.5%, 1.2%, 2.7% and 3.7% for Abies nephrolepis, Betula platyphylla, Picea spp., and Larix gmelinii, respectively. However, carbon densities were increased by 2.9%, 3.9% and 7.2% per year for Alnus sibirica, Pinus koraiensis and Acer ukurunduense, respectively. Net primary production (NPP) of the forest was 4.69 t C · hm(-2) · a(-1). The ratio of belowground NPP to aboveground NPP was 0.56. Litterfall accounted for the largest proportion of the NPP of forest with a value of 34.5%. As the two most important carbon output approaches of forest ecosystems, the fluxes of heterotrophic respiration and coarse woody debris decomposition were 293.67 and 119.29 g C · m(-2) · a(-1), respectively. Net ecosystem production (NEP) of the forest was 55.90 g C · m(-2) a(-1). The results indicated that the valley spruce-fir forest in the declining state still had a certain carbon sink capacity.
authors: Hui-Ying
authors: HY
authors: Cai
authors: Xue-Ying
authors: XY
authors: Di
authors: Guang-Ze
authors: GZ
authors: Jin
mesh_terms: D028202:Abies; D031002:Acer; D029661:Alnus; D029662:Betula; D002244:Carbon / Q000032:analysis*; D057965:Carbon Sequestration; D002681:China; D065928:Forests; D028221:Larix; D028222:Picea; D028223:Pinus; D012987:Soil; D014197:Trees
chemical_list: D012987:Soil; D002244:Carbon