Competition-Productivity Relationship Between Some Common Grasses and Forbs Plant Species in High Altitude Rangelands

Abstract

Facilitation or competition occurs among plant species when one species alter ameliorates the environment for another species or when one species needs the same sources of another species. The objective of this study was to determine to facilitative or competitive effect on Bromus variegatus, Festuca ovina, Koeleria cristata of growing with isolated, Medicago papillosa, Astragalus microcephalus, Thymus parviflorus, and Hypericum scabrum, and arranged in completely randomized design. Plant height, above-and belowground biomass, and above-and belowground Relative Neighbour Effect (RNE) significantly affected main, some first- and second-order interaction depending on the year, grasses species, surrounding. Aboveground biomass increased in grasses, which grow in interaction with legume species, and significant differences were determined between the grass species and years. While average belowground biomass was 26,66 g/plant, the belowground biomass of the grass species grown in interaction with M. papillosa and A. microcephalus was positively affected and it was 31,58 and 34,99 g/plant, respectively. A. microcephalus had a facilitative effect on above ground RNE of the grass species and the other species had a competitive effect. All plant species had a competitive effect on belowground RNE.

Keywords

• facilitation
• competition
• plant-plant interaction
• plant environment