Investigating the habitat requirements of some rangeland plants growing on the soils resulting from the erosion of Gurpi marli formation (Case Study: Chaharmahal and Bakhtiari Province)

The establishment and growth of vegetation on marly lands is usually difficult because of mineralogical properties of marls especially clay minerals aggregation as impermeable fraction in these rocks and sediments. This research aims to systematically investigate relatively densely grown plant species and determine their habitat needs as well as their protective role in the soils resulting from the erosion of the Gurpi marly belonging to the Cretaceous period with a thickness of more than 100 meters in two regions as Vastegan and Dorahan areas in Borujen Township, Chaharmahal & Bakhtiari province.  For this purpose, 65 marl soil samples were taken and physical and chemical tests were performed on 31 samples. Botanical surveys performed using repeated field visits and plat made up on the 180 plots and plant samples were identified after moving to plant museum (Herbarium) of agricultural and natural resources research and education center. In general, more than 400 plant species growing in the region and on different formations. A collection of rangeland species Astragalusbrachycalyx-Daphnemucronata- Cirsiumbracteosum with a density of more than 50% can be present in the lands resulting from the erosion of neutral marl lands(PH =7-8) with moderate  lime amount and without Na+ and Cl- presence can  established and go through its growth stages. In addition, a collection and colony of rangeland species with the combination of Astragalus susianus-Daphne mucronata-Amygdalus elaeagnifolia) can be established in alkaline marl (pH>8) with high amount of lime fraction and cl- and should be presented as a biological solution to control the erosion of the soils affected by the erosion of alkaline marls.