بررسي تركيب فلوريستيكي و غناي گونه اي مراتع قشلاقي يك چنار در استان گلستان

An investigation on plant richness and floristic composition of Yakeh-Chanar winter rangelands in Golestan Province

The species richness and floristic composition in three vegetation types of Yakeh-Chanar winter rangeland at Golestan province were studied by surveying and collecting the flora and using the Whittakerʹ plots. The objectives of this study were to determine the effects of aspect, slope, and elevation on the species richness and floristic composition in three vegetation types. For analysis of species richness, group regression model was used. From stand point of biological types the following relations were obtained: Trophies > Chamaephytes > Hemi cryptophytes> Geophytes> Phanerophytes. From stand point of life forms the relations were Forbs>Grasses> Woody plants. The plant richness inequality of three vegetation types were Woodland> Grassland> Scrubland. The plant richness was usually higher in the north to compare to the south aspects. There were delays in phonological stages as the elevation increased, so when the plants were in vegetative stage at woodlands, the species of grassland were in the flowering stages and most species of the scrubland passed the stages of seed ripening and dissemination. In general, annuals and ephemerals dominated that is the characteristics of the areas with highly variable rainfall. When there is enough rain especially in spring, the seeds of many annuals germinate and species richness highly increases.