Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (9): 1027-1037.DOI: 10.17521/cjpe.2022.0086

• Research Articles • Previous Articles     Next Articles

Analyses of intraspecific competition and facilitation of Picea crassifolia in Pailugou Watershed of Qilian Mountains, China

ZHAO Chang-Xing1,2, ZHAO Wei-Jun3, ZHANG Xing-Lin4, LIU Si-Min5, MOU Wen-Bo1,6, LIU Jin-Rong1,2,*()   

  1. 1State Key Laboratory of Grassland Agro-ecosystems, Lanzhou University, Lanzhou 730020
    2College of Pastoral Agriculture Science and Technology, Engineering Research Center of Grassland Industry, Ministry of Education, Gansu Tech Innovation Center of Western China Grassland Industry, Lanzhou University, Lanzhou 730020, China
    3Academy of Water Resources Conservation Forests in Qilian Mountains of Gansu Province, Zhangye, Gansu 734099, China
    4Gansu Academy of Eco-environmental Sciences, Lanzhou 730030, China
    5National Forestry and Grassland Administration, Beijing 100714, China
    6College of Ecology, Lanzhou University, Lanzhou 730000, China
  • Received:2022-03-07 Accepted:2022-05-13 Online:2022-09-20 Published:2022-10-19
  • Contact: LIU Jin-Rong
  • Supported by:
    National Natural Science Foundation of China(32060247)


Aims Exploring the spatial distribution patterns and interactions of populations can help elucidate the underlying driving factors in population structure construction and the maintenance mechanism of spatial distribution. It guides the allocation, and management of different populations in the forest ecosystems, and also provides a scientific basis for local ecological environment protection and regional resource development.

Methods In this study, Picea crassifolia was selected as the research object. Three repeated plots with an area of 1 hm2 were set up in the Pailugou Watershed of the Qilian Mountains, and all individual trees with a diameter at breast height (DBH) ≥1 cm were measured and recorded. The spatial patterns and intraspecific interactions of Picea crassifolia were analyzed by using a pair-correlation function (univariate and bivariate pair-correlation function) and mark correlation function (marked correlation function, marked variogram function, and Schlather’s I(r) function).

Important findings (1) The diameter class distribution of P. crassifolia population was continuous, with an inverted “J” type structure. (2) Picea crassifolia as a whole, saplings, and young trees showed a small-scale aggregation distribution, and gradually tended to random distribution with the increase of spatial scale. Medium trees showed a random distribution pattern on the whole observation scale, while large trees showed a regular distribution on the small scale and random distribution on the large scale. (3) Large trees of P. crassifolia showed small-scale negative correlations with other size class individuals and middle-scale positive correlations. There were strong positive correlations between medium and young trees, and between sapling and young trees at a small to medium scale, and they gradually changed to no correlation with the increase of spatial scale. (4) Individual characteristics of P. crassifolia showed high correlations, strong inhibitions, and significant symmetry competitions on a small to medium scale.

Key words: Picea crassifolia, spatial pattern, intraspecific interaction, competition, facilitation, point pattern analysis