Journal of Rangeland Science
Volume:6 Issue: 2, Spring 2016

Predictive modeling of habitat distribution of range plant species and identification of their potential habitats play important roles in the restoration of disturbed rangelands. This study aimed to predict the geographical distribution of Artemisia sieberi and find the influential variables in the distribution of A. sieberi in the desert rangelands of central Iran. Maps of environmental variables were generated by GIS software (version 9.3). Predictive distribution maps of A. sieberi were produced with Maximum Entropy Method (MaxEnt) and the existing data regarding this species. The agreement of predictive map with the actual map was checked by calculating Kappa coefficient value. Accuracy of predictive models was evaluated using the Area Under the Curve (AUC). Results showed that soil pH and lime content in the surface layer (0-30 cm) and silt percent in both surface and sub-surface soil depths (0-30 and 30-60) had the greatest impacts on the distribution of A. sieberi in the study area. Correspondence of actual map with the predictive one was assessed at a satisfactory level (Kappa coefficient = 0.70). MaxEnt is widely used as compared with the other standard methods since it only requires the presence data of a specific plant species to draw the distribution map of its habitat. Additionally, MaxEnt is a generative method and its output can be easily understood by the field practitioners.

Adverse changes in rangeland vegetation can be considered as one of the criteria for land degradation. Some of these changes can be evaluated through monitoring the spatial changes of landscape parameters. This study aimed to investigate the landscape changes in Kezab rangelands of Yazd province, central Iran. Landsat satellite images of 1990, 2002, and 2013, and landscape metrics including Total Edge, Edge Density, Mean Shape Index, Number of Patches, Mean Patch Size, and Median Patch Size were used in this study. Landscape fragmentation was analyzed through calculating various metrics of landscape patterns using the FRAGSTATS software. This study was performed with a focus on landscape elements in poor and very poor rangelands. Results indicated a reduction in the area of rangelands with poor conditions and an increase in the size of rangelands with very poor conditions. The results showed that perimeter sum of spots in rangelands increased From 51.6 km in 1990 to 62 km in 2013. This increase in the perimeter showed further destruction of poor rangelands. This process was considerably seen in very poor rangelands and increased from 48.9 km in 1990 to 56 km in 2013. The process of Edge Density index changes confirmed the intensification of desertification in the region. Also, the number of patches in poor and very poor rangelands increased from 23 to 11 and from 4 to 10, respectively. The intensification of destruction has been shown in very poor rangelands. Rangelands were also changed in terms of other landscape parameters, eventually leading to the deformation of rangeland patches and the degradation process has been intensified in this region. According to the results of these studies, landscape changes of rangelands could be assessed at various time intervals to detect the factors affecting rangelands.

FAO and World Bank promote livestock rearing as a way of poverty alleviation and food security especially among rural poor. Villagers are usually involved in mixed crop-livestock farming. Interviews with villagers in the HableRud basin revealed that some changes have happened and comparing with past decades, fewer villagers keep livestock. They believed that number of villagers who kept livestock in pen has also drastically increased. This study was conducted to understand if natural capital holdings have any impact on villager's dependence on rangeland or not and also to identify the important natural capitals contributing to villager's dependency on rangeland, some unstructured and structured interviews with local people were conducted. Comparisons between the two groups of villagers namely, dependent and independent on rangeland in terms of the identified indicators, the independent samples T-test and Mann Whitney U were applied for parametric and nonparametric data, respectively. Then in order to predict likelihood of dependency of a villager on rangeland based on holding of or access to independent variables, binary logistic regression was applied using SPSS. Descriptive data analysis showed that just 177 villagers out of 380 samples were dependent on rangeland and the rest did not rely on rangeland at all. The results revealed that there was a significant difference between the two groups of dependent and independent villagers on rangelands in terms of grazing right, size of farm and orchard holding, number of small livestock, total livestock and total natural capital. But the best indicators to predict a villager's dependence on rangeland was decided to be grazing right, number of small livestock and size of farm. The study revealed that independent variables predict the odds (61% - 82%) that a villager will decide to keep livestock dependent on rangeland.

Water harvesting is the collection of runoff for productivity purposes, instead of runoff being left to cause erosion. In arid and semi-arid drought-prone areas, micro-catchments are widely used as a water harvesting method to improve rangeland condition. The aim of present study was to investigate the effects of micro-catchment on ecological indices of rangeland health in Ghick-Sheikhha, Jiroft, Iran using LFA (Landscape Function Analysis) method. A free micro-catchment area (as control) was selected to compare the effects of micro-catchment on the soil and vegetation cover. In this method 11 soil parameters were assessed (transects of 100m length) to recognize three functional properties, including stability, infiltration and nutrient cycling. Statistical data analyses were done using analysis of landscape function and paird t test to compare the performance indicators in the control and micro-catchment. To determine best factors affecting the health of the range, multivariate regression model was used. The results showed that in the micro-catchment treatment, the length of patches were more than that in the control area. Significant differences were observed between the areas in terms of three indices (p≤0.05). Regression models suggested that the parameters of soil sedimentation, soil resistance to humidity, soil surface roughness and canopy cover in the micro-catchment area and soil surface roughness, litter cover and surface resist to disturb in the control area had respectively, the higher impact on rangeland health indices. Generally, the present study suggested the effectiveness of micro-catchment compared to the control area.

Improving seed germination rate accelerates early seedling establishment, in turn, enhances plant growth and forage production in rangelands and pastures. Rapid and simultaneous germination of seeds leads to successful plant establishment. The ingoing research aims to deals with effect of SiO2 nanoparticles at concentrations of 0, 5, 20, 40, 60 and 80 mg/l on seed germination rate in Astragalus squarrosus. The experiment was conducted for 15 days under constant temperature of 20 °C, 16 h of light and 8 hours dark. The treatments were arranged as factorial based on a completely randomized design with four replicates in Department of Natural Resources at the Ferdowsi University of Mashhad, Iran. The results of experiment showed that the germination percentage of scarified seeds treated with SiO2 nanoparticles with 40ppm concentration was improved compared to control seeds and non-scarified ones treated with nanoparticles. At the same time, some other positive effects of other nanoparticle concentrations on germination rate and percent were obvious so that the effect of different concentrations of nanoparticles on seed germination traits Astragalus squarrosus was found to be significant. The highest and lowest germination percentage was recorded under concentration of 40 ppm and 80 ppm those seeds treated with nanoparticles, respectively. As SiO2 concentration increased, no enhancing positive effect on seed germination attributes of Astragalus squarrosus was found. In this experiment, it was found that seeds scarified and treated with 40 or 60 mg/l of SiO2 nanoparticles showed improved germination in Astragalus squarrosus , so this treatment can be promising for establishment and colonization of this species in natural landscapes.

The aim of this study was to investigate the members’ opinions regarding the influencing factors contributing the success of range management cooperatives in three provinces as Markazi, Tehran and Isfahan of Iran in 2014. The study populations were board and ordinary members of cooperatives (N=750) and the samples were selected using Krejcie and Morgan method through stratified and random sampling (n=98). Data of questionnaires were collected using scaling method. Statistical tests of Chronbach's alpha coefficient indicated high validity and reliability of data. The results demonstrated that the unofficial range management cooperatives were more successful compared to the official ones, but in overall, both cooperatives were not successful in achieving the given goals in the system and satisfying the expectations of members. To study the effects of independent variables on the success of both cooperatives, path analysis and multivariate regression were used. The results showed that the factors of education, technical skills of managers, social participation, financial elements, performance of public departments and knowledge of members as the promotion factors had the most impact on the success of the official cooperatives. For unofficial cooperatives, education, financial fairness, comprehension skills of managers, experience and skills of members and performance of public departments had the highest effects on the success of these cooperatives.

Soil carbon and nitrogen contents play an important role in sustaining soil physical and chemical quality and help to have healthy environments. The continues conversion of rangelands to arable lands has the potential to change carbon and nitrogen sequestration. In this study to evaluate the effects of land use change on soil organic carbon and nitrogen stock, forty samples collected from northwest of Shahmirzad town in Semnan province of Iran. Samples collected from two types of rangelands (Astragalus parrowianus and Acantholimon erinaceum) and Walnut garden in four depth of soil. The values of soils gravel percentage, particle size distribution, bulk density, organic carbon and total nitrogen have been measured and analyzed. Results showed that there is no significant difference in soil organic carbon (SOC) stock values among garden and rangelands but nitrogen stock in garden showed the higher values and had significant difference with rangelands. The C/N ratio in rangelands was similar unlike garden that showed significant decrease. Moreover, the values of soil organic carbon and total nitrogen (TN) stock and C/N ratio have been decreased in subsurface layer of soils. The results of correlation matrix indicated that the values of SOC and TN stock and C/N ratio had the high correlated with soils particle size distribution. Clay percentage indicated high positive correlation while silt and sand demonstrated negative correlation. Overall, in opposite of SOC stock, land use change from rangeland to garden had significant effect on soil nitrogen stock and increased it dramatically while decreased C/N ratio, considerably.

The present research aims to identify and analysis the effectiveness of rangeland management cooperatives in Gonbad city. The study was conducted in 2015. The research was performed in descriptive manner as survey method. The subjects (participants) included all members of rangeland management cooperative in Gonbad city. The sample size was determined by Cochran (n=200). For sampling random cluster method was used. The validity and reliability of questionnaire, was confirmed according to the Task Force and experts of Department of Natural Resources and Watershed Management in Golestan province as well as Alpha Cronbach 0.97 respectively. Factor analysis is one of the aspects of inferential statistics which is used as weight of the raw scores and indeed weighted scores in this section combines the functions of rangeland management cooperative in their success. The final score of rangeland management cooperative function is obtained by multiplying weight average in current score success rate is achieved. Results of factor was led to extracting five analysis extracted as information and extension services, technical support services, collaboration and social interaction, restoring rangelands and suppliers of inputs so that accounted for 74.176 percent of the variance from total variance of variables for range management cooperatives union functions.

This is the second of series on the impact of dust. It focuses on the physical, chemical and physiological effects of dust particles and aerosols. Plants of all types and classes (from algae to forest trees and everything in between) are adversely affected either directly through abrasion by airborne particles or through interference with plant physiology or indirectly through the impact on soil as particles are deposited in the soil surface with effects on the soil chemistry, soil texture and soil structure. The literature that is reviewed spans decades and the biomes from which examples are drawn cover regions from the Arctic Circle to the equator, from deserts to tropical rainforests. The physiological responses of plants underlie and precede ecological changes at the community level and these changes have implications for such important relationships as predator-prey as shelter food supply and other essential ecosystem services either cease to be provided or are severely curtailed. It was found that all species have maximum dust deposition in the winter season followed by summer and rainy seasons. Chlorophyll content decreased and ascorbic acid content increased with the increase of dust deposition. There was significant negative and positive correlation between dust deposition and chlorophyll and ascorbic acid content, respectively.

An Iranian Rangeland ecologist, born in 1937 in Tabriz, He got his MSc. in agriculture in 1961 from Tabriz University. He was hired by Rangeland Improvement and Fodder Procurement Organization in 1963. At the early steps of his career, he worked as the head of Daland Range Seed Production Station in Gorgan, and then he worked as the head of Homand Plant Research Center from 1966. He received his second MSc in rangeland management from University of Wyoming in 1969 and later on got his PhD in 1975 from there. He worked on quantitative study of vegetation of Markazi province- Iran. He was supervised by Dr. Meymandinejad a well known plant ecologist. Dr. Sabeti and Dr. Goodwin worked with him as advisors. He joined Research Institute for Forest and Rangeland (RIFR) as the head of Range Research Division from 1971-1978. He served as the head of Research Institute for Forests and Rangelands during 1978-79 when he noticed that he had cancer and followed some surgeries and pertinent treatment. He followed his research in that institute until retirement in 2001. He taught range ecology, range plant identification, rangeland improvement and development and rangeland management at Gorgan university of Agricultural Science and Natural Resources, Tarbiat Modarres University, Islamic Azad University–Noor Branch. He supervised 65 MSc thesis and 2 PhD dissertations. During his service, he had the opportunity to attend many national and international conferences and some training courses around the world. He also visited some of the famous botanical gardens in Scottland, Austria, Switzerland, Germany and Spain. He conducted many projects to study vegetation of Iran among them he had some projects with international organizations such as IFAD. He also had some projects in Turkmentistan and Pakistan.