Chin J Plant Ecol ›› 2012, Vol. 36 ›› Issue (3): 222-230.DOI: 10.3724/SP.J.1258.2012.00222

Special Issue: 生态化学计量

• Research Articles • Previous Articles     Next Articles

Leaf nitrogen and phosphorus stoichiometry in 80 herbaceous plant species of Songnen grassland in Northeast China

SONG Yan-Tao1, ZHOU Dao-Wei2,*(), LI Qiang2, WANG Ping3, HUANG Ying-Xin2   

  1. 1Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China
    2Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012, China
    3School of Urban and Environmental Sciences, Northeast Normal University; State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Changchun 130024, China
  • Received:2011-07-11 Accepted:2011-12-16 Online:2012-07-11 Published:2012-02-28
  • Contact: ZHOU Dao-Wei

Abstract:

Aims Leaf nitrogen (N) and phosphorus (P) and N : P stoichiometry have been studied intensively in different regions in China. Songnen grassland is a natural region. Its dominant vegetation is meadow, which is determined by soil properties, and its flora is complex. Our objective was to find the stoichiometric patterns for this region.
Methods Leaf samples of 80 herbaceous species were collected in Songnen grassland in August 2008. We determined leaf N, P, and N : P on both a mass and an area basis and tested the differences according to plant life forms and functional groups.
Important findings Leaf N and P concentrations were (24.2 ± 0.96) and (2.0 ± 0.10) mg·g-1 on a mass basis and (13.0 ± 0.54) and (1.0 ± 0.05) mg·cm -2 on an area basis, respectively. N : P was (13.0 ± 0.39). Plant growth was limited by N in Songnen grassland. The concentration of leaf N and P and coefficient of variation were higher in annual plants than in other life forms on a mass basis, and there were no significant differences of leaf N concentration on an area basis and N : P between different life forms. Leaf N concentrations both on mass and area bases and N : P of legumes were higher than in other functional groups. There was no significant difference in the leaf P concentrations on an area basis among different life forms or functional groups. Our findings indicate that appropriately increasing the proportion of legume plants would improve both the yield and quality of primary productivity in Songnen grassland.

Key words: ecological stoichiometry, leaf nitrogen (N) and phosphorus (P) concentration, N : P, plant functional group, Songnen grassland