Chin J Plant Ecol ›› 2012, Vol. 36 ›› Issue (12): 1248-1255.DOI: 10.3724/SP.J.1258.2012.01248

Special Issue: 青藏高原植物生态学:群落生态学

• Research Articles • Previous Articles     Next Articles

Effect of sampling scale on the relationship between species diversity and productivity in subalpine meadows

YUAN Zi-Qiang, WEI Pan-Pan, GAO Ben-Qiang, ZHANG Rong*()   

  1. Institute of Arid and Agro-ecology, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
  • Received:2012-08-09 Accepted:2012-10-07 Online:2012-08-09 Published:2012-11-28
  • Contact: ZHANG Rong

Abstract:

Aims The relationship between species diversity and productivity has been a central issue in the face of increasing species extinctions; however, this issue has resulted in many disagreements. Our objectives were to determine (1) forms of the relationships between plant species diversity and productivity in natural communities in subalpine meadow and (2) effect of the sample area on the relationship between plant diversity and productivity. Methods We evaluated the relationships between species diversity and productivity by sampling three different study sites in subalpine meadow in the Hezuo region of Gansu Province, China in 2010. These three sites have different land use histories and altered vegetation traits. Sampling areas in each site were 0.01, 0.04, 0.16 and 0.64 m 2. The number of samples was 30 for each site. Sampling at each site was conducted randomly. In August 2010, we determined the aboveground, oven-dried biomass and the number of plant species in each sample quadrat. The relationship between species diversity and productivity was constructed by linearly and quadratically regressing both number of species and aboveground biomass. Important findings We found no significant relationship between number of species and aboveground biomass in two of the three sites, even though sampling areas were varied, and the relationship changed with sampling area in another experimental site that had been overgrazed. Both sampling area and study site had significant effects on number of species, while number of species in each sample increased with sampling area and aboveground biomass per unit area was constant, i.e., sampling areas had no effect on productivity. Variation of experimental site had a significant effect on aboveground biomass, and productivity of each site was not closely dependent on number of species but the site. Results suggest that there may be no fixed relationship between species diversity and productivity in natural communities of subalpine meadow.

Key words: community productivity, ecosystem functioning, sampling scale, species diversity, subalpine meadow