This research is an integration of GIS and multi-criteria decision making into a joint framework for identifying suitable areas for rainwater harvesting structures. The Kavir National park in Iran has been evaluated for suitability of rainwater harvesting. To this end, slope gradient, distance to guarding stations, distance to watering points for transporting collected water, distribution of wildlife species of interest, access to roads, evaporation, elevation, water scarcity index, and annual precipitation during rainy season were incorporated. Data collection and field visits took place during 2014-2015. Rainwater harvesting in this area is primarily intended for Ovis orientalis, Gazella dorcas and Acinonyx jubatus known as Persian Cheetah. The primary layers were standardized using a proper Fuzzy Membership Function, which assigns a weight between 0 and 1 to each layer, to include the inherent tradeoff between data layers in producing the final suitability map. The results suggested that precipitation and water scarcity (each by the relative weights of 0.3 and 0.2, respectively) were the most influential factors. The northern foothills of the Mount Siahkouh have shown to hold the highest suitability for rainwater harvesting. The suitability changes from lower than 100 to the east to higher than 200 to the west. The result of this study might be used to guide future endeavors for rainwater harvesting for wildlife on the ground. The methodology adopted here could be replicated in other studies with respect to its simplicity and practicality. This is recommended to run pilot small-scale rainwater harvesting practices and receive the outcomes and then, in case of a positive feedback, extend its application to other areas identified in this research. تفاصيل المقالة

One of the major issues examined in the quantitative ecology is the spatial distribution pattern of plant species. Knowledge of the spatial distribution patterns is essential to measure the level of uniformity in the surrounding environment, plant reproduction, and distribution of the seedlings, plant behavioral patterns, coexistence, allelopathic relations, and competition. Therefore, the aim of the present research is to select suitable indicators to determine the spatial distribution of three plant species namely Seidlitzia rosmarinus, Cornulaca monacantha and Stipagrostis plumosa and to evaluate their accuracy in arid and semi-arid rangelands of Birjand. Sampling was taken in the key area of ​​each site with four transects of 100 m using quadrates (with their size proportional to the vegetative form of the plant species) by a stratified random sampling technique in 2014-2015. At each point, the distance from the nearest neighbors, the closest species and species richness were recorded. S. plumosa and S. rosmarinus produced the largest and smallest values as 6.6 and 0.24 plant/m2, respectively. Our results suggested that S. rosmarinus, C. monacantha and S. plumosa follow regular and uniform distribution patterns. The results of the statistical analysis also showed the positive binomial distribution for these species, which further confirm our finding. In total, it has been found that quadratic indicators provide more accurate results regarding plant species distribution patterns as compared with the distance indicators. تفاصيل المقالة

In this research, the impact of a carbon sequestration project, in the Hossein Abad Plain in Southern Khorasan Province of Iran, on the status of water and wind erosion was evaluated. The study area has a harsh climatic condition with low annual precipitation and is prone to well-known 120-day winds in summer. Since 2005, various soil conservation treatments (plantations, over-sowing, plantation aided by semi-circular rainwater harvesting structures) have been implemented in the area. The importance of this research is that so far there was no comprehensive assessment to indicate the impact of soil conversation measures on soil erosion. Therefore, current research aims to evaluate the effect of the carbon sequestration project on soil erosion during 2004 - 2016. Therefore, water and wind erosion was assessed by the Universal Soil Erosion (USLE) model and Iranian Research Institute of Forest and Rangelands Ekhtessasi – Ahmadi (IRIFR-E.A.) model, respectively. The general trend of water erosion using the USLE model indicates a reduction in soil erosion by greater than 19.9 t. ha-1. yr-1 over the whole study area which is larger than 2300 km2. Accordingly, all treatments had a significant impact on erosion in the study area whereby the greatest reduction in annual rate of erosion occurred in over-sown areas (by 5.92 t. ha-1. yr-1). The lowest erosion rate in 2016 was observed in the afforested areas (3.0 t. ha-1. yr-1). Wind erosion during 2004-2016 was improved from moderate and high erosion intensity classes to the low class in treated areas. According to the results of the USLE and IRIFR-E.A. models, the implemented carbon sequestration project has effectively reduced soil erosion in the study area. Therefore, the continuation of these treatments as well as extension programs to empower local communities is highly recommended. تفاصيل المقالة

Land-use and land-use change can directly affect soil organic carbon. Improper land management can lead to carbon loss from the soil, which can greatly intensify global warming. Despite the abundance of evidence on Soil Organic Carbon (SOC) in Iran, no paper has so far compiled the data for this region. Therefore, data were collected from 120 papers and 393 data points regarding land use and SOC changes. Stepwise regression analysis was used to analyze the relationship between SOC with annual precipitation, average annual temperature, latitude and average depth of sampling. Pearson correlation coefficients were calculated between SOC and other factors. Based on the results, primary forests and reforested areas had significantly higher SOC stocks at the depth of 20cm with average values of 70.03 (±4.45) Mg C ha-1 and 84.38 (±9.01) Mg C ha-1, respectively while there were no significant differences among other land use categories. The findings of this study showed no changes in SOC stocks among land-use change categories and average annual rates of SOC changes. However, among farmlands, evidence was obtained for a significant SOC reduction in cases with a historic forest land-use (-15.2%) compared with those with historic grassland use. Results indicated that farmlands and primary forests had the highest level of SOC input from litter and fine roots, respectively. By evaluating the impact of different factors on SOC using a stepwise regression analysis, it was demonstrated that 31% of the variations in soil carbon storage at different land-use types can be explained by precipitation, temperature, latitude, and sampling depth. Using the obtained equation, SOC variation in Iran was simulated and mapped showing that except for a narrow strip in northern Iran, the rest of the country suffers from low SOC levels. Totally, protecting forests against land conversion is recommended as the top priority for land managers in Iran. تفاصيل المقالة