title: [Root biomass of different stand-age Pinus yunnanensis forests and its distribution pattern in different soil depths].
abstract: With average-tree-specific sampling method, the authors measured the root biomass of Pinus yunnanensis forests with different stand ages in Yongren County, Yunnan Province. The results indicated that total root biomass increased from 8.50 t x hm(-2) in young stand (15-17 yr) to 11.70 t x hm(-2) in middle-aged stand (30-32 yr), and to 18.91 t x hm(-2) in mature stand (60-130 yr). Among different stand age classes, the biomass of coarse roots (>10 mm) varied greatly (1.5-12.3 t x hm(-2)), whereas those of medium (5-10 mm) and fine (<5 mm) roots showed less variation (medium roots 1.4-1.6 t x hm(-2), fine roots 5.3-6.2 t x hm(-2)). The root biomass of mature stand decreased with soil depth, approximately 93% of total underground biomass being distributed in surface layer (0-30 cm), and only 7% in deeper layer (30-115 cm).
authors.affiliation: Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing. dengkm@igsnrr.ac.cn
authors.forename: Kunmei
authors.initials: K
authors.lastname: Deng
authors.forename: Tianxiang
authors.initials: T
authors.lastname: Luo
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Xueyun
authors.initials: X
authors.lastname: Wang
authors.forename: Changhui
authors.initials: C
authors.lastname: Li
mesh_terms: D002681:China; D017753:Ecosystem; D028223:Pinus / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development*; D012987:Soil / Q000032:analysis
chemical_list: D012987:Soil