Chin J Plan Ecolo ›› 2015, Vol. 39 ›› Issue (5): 453-465.DOI: 10.17521/cjpe.2015.0044

Special Issue: 生态化学计量

• Orginal Article • Previous Articles     Next Articles

Environmental heterogeneity and mechanism of stoichiometry properties of vegetative organs in dominant shrub communities across the Loess Plateau

LI Dan-Feng1,2, YU Shun-Li1,*(), WANG Guo-Xun1,3, FANG Wei-Wei2,4   

  1. 1State Key Laboratory of Vegetation and Environmental Changes, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
    3College of Life Sciences, Northwest University, Xi’an 710069, China
    and 4Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China
  • Received:2015-01-22 Accepted:2015-03-31 Online:2015-05-01 Published:2015-05-26
  • Contact: Shun-Li YU
  • About author:

    # Co-first authors

Abstract: Aims

Exploring variation patterns of C, N, P contents and their ratios of plant vegetative organs along environmental gradient can provide insight on the resource allocation strategy of plants. In order to search the environmental heterogeneity and mechanism of stoichiometry properties of plant vegetative organs (including root, stem and leaf), we investigated the influences of different soil nutrients conditions on the element allocation among plant vegetative organs in the dominant shrub communities along a hydro-thermic gradient across Loess Plateau.


The species compositions and structures of 123 small quadrats (5 m × 5 m) of dominant shrub communities in 41 sites were investigated by standard community sampling method along the declined hydro-thermic conditions from southern Gansu Province to northern Ningxia Hui Autonomous Region and western Gansu. The data about height, coverage and number of the dominant shrub were recorded. At least 369 biological samples of plant vegetative organs (root, stem and leave) of dominant shrubs were collected and their fresh and dry mass were measured, respectively. About 123 soil samples were taken by earth boring auger and ring knife. C, N and P contents of all biological and soil samples were measured after lapping and sieving.

Important findings

1) Organic matter content (mean concentration of leaf C ((424.11 ± 42.21) mg·g-1) in Gansu and Ningxia Hui Autonomous Region was relatively low, and nitrogen (mean concentration of leaf N ((23.00 ± 8.09) mg·g-1) was higher while phosphorous (mean concentration of leaf P ((1.18 ± 0.50) mg·g-1) was relatively deficient. 2) Along the increasing growing season temperature and declining annual precipitation from southern Gansu to northern Ningxia Hui Autonomous Region and western Gansu, soil nutrients content decreased, and the storage of C, N and P in root, stem and leaf decreased. The shift trends of C:N agreed with the N storage’s shift trends in root and stem while N:P in all organs were contrary to the P storage’s shift trends. Meanwhile, the allocation patterns of C, N and P among vegetative organs among the three regions dominated by shrub communities were much different. 3) In the region with high soil nutrients, the nutrient storage in vegetable organs were similar among different species in the same dominant shrub regions, but in the regions with low soil nutrients, the nutrient storage in vegetable organs displayed high variations. The variations of nutrient storage of vegetable organs for the same shrub communities from different regions were not significant.

Key words: stoichiometry properties, dominant shrub communities across Loess Plateau, coupling, hydro- thermic factors, resource allocation