Ecological groups of vegetation based on climatic factors in summer rangelands of Behshahr

Vegetation is affected mostly by climatic factors, therefore a knowledge of relationship between vegetation and these factors shows the distribution of plant communities and it is important step for management of the summer range ecosystems. The present study was carried out in summer rangelands of Behshahr to find the relations between vegetation and climatic factors. According to aerial photos, topographic maps and field surveys; five plant communities were separated by the floristic-physiognomic method. In each community, samples were taken based on random-systematic method. After selecting key areas, plot shape and size was determined using statistical and minimal area methods. Importance value of species, temperature and precipitation data was recorded in each community. The relations between dominant plants of communities and climatic data were determined using ANOVA and ordination techniques. The results show that response of the plant communities to climatic factors was different. Bushy tree community (Rosa iberica) with more humidity and less thermal requirement was independent to other communities and grasses (Festuca ovina, Stipa barbata) due to compatibility with drier conditions were in separated group. Shrubs distribution (Acantholimon pterostegium, Onobrychis cornuta) with medium range of temperature and precipitation showed a group.