Investigating the application of petroleum mulch in stabilization of sand and sand dunes in the development of vegetation in Aran and Bidgol region

A large part of Iran is located in dry regions. Accordingly, various provinces are exposed to sand dunes during permanent and seasonal winds. Aran and Bidgol (in Kashan), which is located in the North of Isfahan province, is exposed to sand dunes during the spring winds blowing from the North-West and the summer winds blowing from the North-East. Due to the damages caused by the sands for the farmlands, residential areas, roads, ways, and infrastructures, the stabilization of sand dune in these regions appears to be essential. The present study introduces different types of petroleum mulch, mulching strategy, biological stabilization by means of adaptable plant species in the region, and a number of significant plants of this area. The results indicated that different plant species have covered about 1123678 hectares (73.64%) of the region. In addition, farmlands with 63107 hectares (4.14%), areas without vegetation with 310816 hectares (20.37%), stony lands with 27664 hectares (1.81%), and urbanized areas with 743 hectares (0.05%) spread across the region. The most significant plant types were identified and distinguished using floristic studies. The results indicated that using petroleum mulch creates a protective layer on sand dunes and temporarily stabilizes them. However, in the regions with better annual rainfalls, mulch coverage avoids the rain from penetrating into soil and increases its evaporation. Furthermore, petroleum mulch increases the thermal factor of the soil. In parts where the mulching is not carried out effectively or the mulch layer is very thin, sand hill erosion was observed. As a result, the best method for the stabilization of sand dune is soil maintenance and recovering its vegetation.