The 18-year impact of rainfall storage projects on vegetation in steppe rangelands(Case study: Rangelands less than 100 mm of rainfall in Yazd province)

To investigate the effect of biomechanical methods on increasing the vegetation in arid areas, three regions (Ashkezar, Ghahar, and Chahmatk of Ardakan) in Yazd province were selected. Statistical sites were determined within the scope of rainfall storage operations and outside it (control), and at the end of the growing season (May 2018), a survey was conducted. To do this, in each area, 100 plots of 9 square meters (3*3) at a distance of 12 meters from each other and along five transects of 300 meters, which were considered in parallel and at a distance of 100 meters from each other were placed. In each plot, canopy cover percentage and density of different species were measured. Data were compared with a t-test. The results indicate an increase in the canopy within the furrow and crescent. The canopy average in the Ashkezar and Chahmatk of Ardakan rangelands in the rain storage region increased from 2 to 3% compared to the control area. Also, an increase in the density of different species was observed in the precipitation storage area. However, sowing has been done only in the year of rainfall storage. In general, due to vegetation status and plant density by species segregation, performing remedial storage operations along with seeding using Artemisia sieberi and Salsola tomentosa species can be successful for desert rangelands with less than 100 mm of rainfall.