Effects of constructing small arc basins system on rangeland production and some soil properties in arid lands (case study: Steppic rangelands of Sarbishe, South Khorasan Province)

Water harvesting methods such as small arc basins have been identified as effective methods to increase forage production in rangelands. In this study, the effects of these small arc basins on forage production, soil moisture and soil texture conditions were investigated. A systematic-random sampling was used to collect data from three transects established perpendicularly to the dominant slope of the study area. Productions of range plants were measured in 40 samples (at the end of spring) and then dried in shadow and weighed. One hundred sixty samples were collected from 0-20 and 20-40 cm of soil surface at the beginning and the end of rainfall season. Data were analyzed by General Linear Model (GLM) procedure. The results indicated that the used water harvesting method resulted to a significant two times increase of plant productions in compare with the control site (p<0.01). Also the findings of this study indicated that the main interaction effect of depth, season and sampling area on soil moisture fluctuations were significant (p<0.01). The results also showed that the construction of this system had a positive effect on the texture and silt content of soil in the study area. Therefore, this method can be suggested as an appropriate method for storing rainfall and increasing forage production in rangeland ecosystems.