Ecophysiological relationships between domimant grasses and forbs species in rangelands

The relationships among plant species have an important role in the formation and functions of vegetation depend on climate, environment and plant properties. These relationships can change from positive to notr or negative, and or reverse way depend on environmental conditions. For this purpose, ecophysiological responses were investigated between dominant grasses species (Festuca ovina, Bromus variegatus ve Koeleria cristata) and forb species (Medicago papillosa, Astragalus microcephalus, Thymus parviflorus ve Hypericum scabrum) in high elevation rangelands. The study was carried out according to a completely randomized plot experiment design in split plot arrangement ten replicates at between 2013 and 2014. In the study, botanical composition, spatial pattern, relationships between vegetation and soil properties, available nitrogen, dry matter production, root dry matter production, competition aboveground and beloweground, plant high, crude protein, notral detergent fibre (NDF), acid detergent fibre (ADF) and relative feed value (RFV) were investigated. There was 39 plant specien in the rangeland site and dominant plant species were grasses in the botanical composition. Average grasses ratio were 40,69%. It was observed that there was a strong relationship between the spatial pattern of the species evaluated as media and a patcy distribution in the vegetation. There also was significant differences available soil nitrogen content (NH4 and NO3) between the years. Average NH4 and NO3 was found to be10,96 and 11,73 ppm, respectively. Dry matter production increased in grasses grown in interaction with legume species, and significant differences were determined between the grasses species and years. While average root dry matter production was 26,66 g/plant, the root dry matter production of the grasses species grown in interaction with M. papillosa and A. microcephalus was positively affected and it was 31,58 and 34,99 gr/plant, respectively. There were significant differences both above and below ground competition grasses grown in interaction with plant species and years. While A. microcephalus had facilitative effect on grasses species above ground competition, the other species had competitive effect. All plant species had competitive effect on below ground competition. Plant height showed significant differences according to media, grasses species and years. Media, plant species and years was significantly affected crude protein content, NDF, ADF and RFV. Average crude protein content 10,70%, the highest crude protein content obtained from B. variegatus species grown in interaction with A. microcephalus species. According to the results, determining relationships between species in rangeland vegetations which have with live and dynamic structure, and making decision toward to desired direction of succession will contribute to prepare suitable range management plans with respect to sustainable use of resources.