Biosystematics of Endemic Gypsophyte Populations in Semnan, Iran

Ecological adaptation in specific ecosystems, such as Semnan Province gypsum communities, leads to the biodiversity of endemic plants. Gypsum desert ecosystem of Iran, Despite their immense ecological values, have been less investigated for gypsophyte vegetation with much reserch on the biological conditions of endemic gypsophyte species and understanding their compatibility. To achieve this objective, the following activities were undertaken: ۱) Identificating of plants in gypsum zaone of ۳۰,۰۰۰ hectares, ۲) Investigating of the relationship between principle ecological factors and plants, ۳) Grouping plants relative to soil gypsum and lime contents and altitude and ۴) Comparising of the anatomical, micro-morphological and ecological characteristics of the species of Astragalus semnanensis Born & Rech.F. ،Astragalus fridae Rech.F. ، Gypsophila mucronifolia Rech.F و Motkia gypsaceae Rech.F. Ecological data and soil samples were collected. ۴۷ plant species, including ۶ endemic species of Semnan and ۲۰ endemic species of Iran were identified, and were grouped using CCA and DCA grading analysis, as gypsophytes (G۱) at altitudes of ۱۶۰۰ to ۲۲۵۰ m, including the species Astragalus fridae and Motkia gypsaceae, limestones (C) at an altitude of ۱۵۰۰-۱۷۰۰ m, have Acanthophyllum microcephalum , gypsophytes (G۲) at ۱۳۰۰ to ۱۶۰۰ meters with Astragalus semnanensis and halophytes (H) with Artemisia sieberi species at altitudes of ۱۱۰۰-۱۳۰۰m above sea level. There is a positive correlation between indicators of biodiversity and height and gypsum and a negative correlation between these factors and the sodium content, EC and soil pH. The adaptabilities of some gypsophytes show, although biologicall factors which are themselves affected by the climate, are important in determining the adaptability of plant species, the genetic variation of species over the course of time that provide conditions for endemic species propagative in specific substrates such as gypsum.

کلیدواژه ها:

gypsophyte ، calciphyte ، halophyte ، Semnan endemic plants