Arid Zone Research ›› 2021, Vol. 38 ›› Issue (2): 545-552.doi: 10.13866/j.azr.2021.02.26

• Ecology and Environment • Previous Articles     Next Articles

Effects of stand density on the biomass allocation and tree height-diameter allometric growth of Picea schrenkiana forest on the northern slope of the western Tianshan Mountains

LI Zongying1,2(),LUO Qinghui1,2,XU Zhonglin1,2()   

  1. 1. College of Resources and Environmental Sciences,Xinjiang University, Urumqi 830046, Xinjiang, China
    2. Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi 830046, Xinjiang, China
  • Received:2020-07-26 Revised:2020-09-01 Online:2021-03-15 Published:2021-04-25
  • Contact: Zhonglin XU E-mail:li_zyxju@163.com;galinwa@gmail.com

Abstract:

Picea schrenkiana is the dominant species widely distributed in the mountain forests on the northern slopes of the Tianshan Mountains. Determining the effects of individual density on the biomass allocation and height-diameter allometric relationship of P. schrenkiana forest is important to clarify the adaptation strategy of P. schrenkiana in different environments. In this paper, the effects of individual density on biomass allocation and the height-diameter allometric relationship of P. schrenkiana forest were studied based on fields investigations of P. schrenkiana forest with different stand densities (<300, 300-450, 450-600, >600 plants·hm-2). The results showed that the average biomass of all biomass components and branches alone decreased in P. schrenkiana forest when stand density increased. However, the biomass proportions of stems and roots increased, whereas the proportions of leaves and bark were stable. Both the height and the diameter at breast height (DBH) of the P. schrenkiana individuals decreased with increased stand density. Additionally, this study found that the relationship y=2.312 × x0.900 can be used to reliably delineate the allometric growth relationship between the height (H) and the DBH (D) of P. schrenkiana individuals (R2=0.761, P<0.01). With the increase in individual density, the relationship between lgH and lgD of P. schrenkiana individuals showed a complex nonlinear allometric growth relationship, and the significance of the relationship gradually reduced with density. This indicates that density had an impact on the resource competition of individuals and affected the growth of organs. The results can be used to inform the sustainable management of P. schrenkiana forest.

Key words: stand density, picea schrenkiana forest, biomass, allometric growth