Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (5): 713-723.DOI: 10.17521/cjpe.2022.0331

• Research Articles • Previous Articles     Next Articles

Case verification of community structure determining community productivity in subalpine meadow

LI Wei, ZHANG Rong*()   

  1. State Key Laboratory of Grassland Agroecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
  • Received:2022-08-17 Accepted:2022-11-11 Online:2023-05-20 Published:2022-11-11


Aims In studies on the relationship between plant species richness and productivity, species richness is regarded primarily as an independent variable and productivity as a response variable, whereas other factors that may affect community productivity at the same species richness levels, such as species combination and composition, are largely ignored. The objectives of this research have been determined: (1) the effect of community structure on community productivity, including species combination, composition, and functional groups to which the species belongs, and (2) the relationship between species richness and community productivity in subalpine meadow communities.
Methods In the pot experiment, seeds of four plant species (Festuca sinensis, Elymus nutans, Medicago sativa and Dactylis glomerata) were sown to pots in terms of given species combination and composition at varying levels of species richness (1, 2, 3, 4). In both monocultures and mixtures, the overall planting density of the community was 100. Seeds were sown in equal numbers to pots in communities of diverse species combinations at various levels of species richness. The species composition of four-species mixed-seeding communities was designed as 10%, 20%, 30%, and 40% density proportions, respectively. Each treatment had five replicates, and weeds were manually removed on a regular basis. The above-ground biomass in each pot had been harvested, dried, and measured by species at the end of September.
Important findings Community productivity increased with increasing species richness at lower species richness, but not substantially at higher species richness, The combination and composition of community species had a significant effect on community productivity, with the mixed-seeding community containing Elymus nutans and communities with a high proportion of Elymus nutans having higher productivity. Among the functional groups to which the species belonged, legumes either promoted or inhibited the production of other species. Elymus nutans enhanced community productivity, whereas Festuca sinensis and Dactylis glomerata had no discernible effect. As a result, it could be inferred that there is an apparent relationship between species richness and productivity, and plant community productivity is more dependent on species combination and composition than on species richness.

Key words: plant functional group, species richness, community productivity, community ecology, subalpine meadow