Study of habitat characteristics of Capparis spinosa in some ecosystems of Sistan region

A large part of Iran is occupied by arid and semi-arid regions with high vulnerability. Native plant species that are adapted and resistant to the onerous environmental conditions of these areas have particular importance in the sustainability of this ecosystem as well as livestock nutrition and providing the medicinal needs of local communities. With scientific and practical knowledge about the ecological characteristics of plants in each region, not only can prevent destructive factors and their regressive trend, but by making reasonable decisions, we can take steps to maintain, recover and develop them. Plant growth in natural habitats is the result of the function of various biological factors such as climate, soil, and topography, so identifying these factors as habitat needs of plants is the first step in their protection and restoration. This study was performed aimed to investigate some habitat characteristics‎ of Capparis spinosa as a medicinal plant and effective in preventing wind erosion in Sistan.

The distribution areas of Capparis spinosa were determined firstly with the help of the experiences of experts from Agricultural Research Centers and the Department of Natural Resources, and field visits in Sistan region. In order to study the vital changes of the plant in three habitats Zahak, Hirmand, and Hamoon, investigation of the phenological stages during the plant activity period was performed by regular visits on specific points at vegetative year 2019. Vegetation measurements were done in a random-systematic method at each site. Four transects were considered with length 200m and 100m away from each other. On each transect 10 plots two-by-two located and some characteristics‎ were estimated consisting of canopy cover, density, frequency, percentage of litter, sand, gravel, and bare soil. A sampling of soil was done from each habitat in order to investigate physical and chemical properties by 4 composite samples (from the first and last plots). Morphological traits (number of fruits, wet weight of fruit, dry weight of fruit, number of stems, plant height, leaf length, leaf width, and root depth) in each habitat were measured from four plant stands randomly. Data analysis was performed using analysis of variance (ANOVA) by IBM SPSS Statistics 26.0 and principal component analysis (PCA) using Past4.0.

The results of the vegetative period of Capparis spinosa ‎ showed that the first leaf emerges in early March and the end of the vegetative period happened in December and the plant has two flowering (June and October) and seeding periods (July and November) in years. There were significant differences between habitats in the aspect of quantitative characteristics of vegetation and morphological traits. Hirmand habitat has more cover percentage, frequency, density, litter percentage, fruit number per plant, number and length of stem, and rooting depth than the other two sites. It also grows with species such as white saxaul (Haloxylon persicum), tamarix (Tamarix ‎aphylla), bindii (Tribulus terrestris), Alhaji camelerom, halsola (Salsola rigida), shrubby Seablite (Suaeda fruticosa), bermuda grass (Cynodon ‎dactylon), harmal (Peganum harmala), tumbleweed (Salsola Kali), desert grass (Stipagrostis plumose), Citrullus colocynthis and colocynth (Seidletzia ‎rosmarinus). The soil of Hirmand was more acidic (8/7) and had higher levels of lime (8/7), sand (86/7), Cilt (8/9), organic carbon (0/6) and organic matter (0/8) than other habitats. PCA revealed that the soil texture and height were the most important factors affecting the distribution of this species. Soil texture, and height were not different in the three habitats.

Investigation of different phenological stages in the plant activity period showed the simultaneous growth of this plant with 120-day winds of Sistan region (120-day winds in Sistan start in early June and continue until the end of September), therefore it is possible preventing of destructive environmental phenomena by planting this species in Eolian harvesting zones. Moreover, this species have medicinal importance and a long vegetative period which has increased the importance of species cultivation in the region. Since the three habitats studied are in poor condition, it is recommended to rehabilitate areas with the cultivation of this species, especially in Helmand habitat, which has more favorable conditions in terms of soil and micro-climate characteristics.