Harvester ants are known as one of the most renowned bio-disturbances in the arid and semi-arid ecosystems that affecte vegetation by collecting seeds and harvesting plants. It seems that physiognomy of plant association in steppe shrub land of Roodshoor, Saveh, Iran has been highly changed by harvester ants’ activities that caused to conduct this research. The study was carried out on active and inactive nests and control site from June to August 2012. Diversity indices and functional groups such as vegetative form, longevity, and photosynthesis type were analyzed as compared to criteria in three sites. Results showed that richness, diversity, and vegetation cover in the ant colonies through increasing the annual forbs and rare species (Campanula stricta and Lepidium vesicarium) were more than the control site. For evenness index, however, there was no significant difference between the control and nest sites. In contrast, the function of plant community in the active nests due to the decrease of dominant shrub frequency of the area that is Artimisia siberi by Messor spp. was less than the control site. Low diversity, richness, plant function, and high vegetation cover in inactive nests were also observed as the results of the presence and activities of the ants in the active nests. Hence, the ant activities in the active and inactive nests can bring out micro sites with different plant associations so that regarding high density and quantity of the ant nests in all the area, it can decrease the key plants and change their functions. It therefore will debilitate the stability and function of this rangeland ecosystem. Manuscript profile

Mountainous rangeland ecosystems have a highly delicate position in ecologic areabecause of severe environmental conditions and having wildlife and livestock. Knowing andrealizing the biotic and abiotic components, which have an interaction with each other in thisecosystem, perform the most important role in to desirable management of it. The systematicmanagement is one of the managing features such as modern approach for land managementand suitable use of upland ecosystems. To reach that, mountainous rangelands of Javaherdeh(Ramsar) via 1:25,000 scale map were selected. Density, rangeland conditions, vegetationcover, gravel and grit were determined by Superficial and modified six-factor methods, ArcGIS v.9.3 software was employed to achieve land form map which was obtained by thecombination of altitude, slope, and slope aspect maps. First, basic and first environmental unitmaps were changed with land form map into soil type map, and first basic map intovegetation type map. The proposal map of systematic management of area was associatedwith final environmental unit map into landuse map via their attribute table. The establishedproposal map shows accurate position of different future land uses on the basis of currentecological capabilities of areas. Around Javaherdeh village is suitable for extensive outdoorrecreation (7.59%) and appropriate for the grazing of livestock (62.22%). Some areas(20.07%) also should be protected because of landslides and debris formation. Manuscript profile

Livestock grazing is one of the most important kinds of land usage that has a high potential to decrease or increase carbon storage in rangeland ecosystem. This research was investigated the effects of enclosure on soil carbon storage in a rangeland with dominant plants of Artemisia aucheri. Hence, two rangelands of enclosure (Shahtappeh-Chah Mahmood) and no enclosure (Chiro) were chosen in Semnan province, Iran. For soil sampling, 20 plots of 1x1 m2 along with two vertical transects with 100 m length were used in each region. Then, two profiles were dug in 0-15 and 15-30 cm depths in soil of baseline and inter-path of plants in each plot. Data were collected for pH, EC, CaCO3, saturation moisture, soil texture, organic carbon (OC%) and s organic matter (OM%), Soil bulk density and Soil carbon storage and the mean was compared by t-test. The results showed that there was a significant difference (P<0.05) between OC% and OM% of baseline in enclosure and no enclosure rangeland. Soil OC% and OM% in baseline in the first depth was more than the second depth in two study areas. There was a significant difference (P<0.05) between soil OC% and OM% in baseline and inter-path of plants in two depths of enclosure and no enclosure rangelands. Soil bulk density (gr/ha) in baseline and inter-path of plants in 15-30 cm was more than 0-15 cm. In enclosure and no enclosure rangelands, grazing had no significant effects on soil organic carbon storage of baseline in each depth. So, the total carbon in 0-30 cm in each region was 47.46 and 40.85 ton/ha, respectively. There was a significant difference between carbon storage of baseline and inter-path of plants (P<0.05) in two depths in enclosure and control rangelands. It was concluded that higher carbon sequestration occurs in the soil, the soil biological and mechanical activities can increase. Manuscript profile

Soil salinity is one of the important factors which can influence the growth anddistribution of plant species. Saline and alkaline rangelands of Golestan Province, Iran withlow-deep underground water level are considered as a halophyte plant species growing area.Attempts have been made to determine soil salinity and its relationship with Frankenia hirsutaL. In order to determine the Electrical Conductivity (EC) of soil, three soil samples had beentaken in the flowering stage of Frankenia hirsuta from the soil at depth of 0-30 cm in threeundergrazing, exclosure and control areas (where there was no Frankenia hirsuta). Data werecollected and analyzed for soil Electrical Conductivity (EC). Results showed that there was asignificant difference (P≤0.01) among three sampling areas (exclosure, undergrazing andcontrol). High EC values were obtained for control area. So, the presence of this species insaline and alkaline rangelands was highly affected by soil salinity. Soil salinity in the controlarea was 39% higher than undergrazing area. Manuscript profile

The study of the relationships of the plant species with the soil in a salty ecosystem would play a significant role in the ecologic programming and management of these inhabitants. The saline and alkaline rangelands of the Golestan province are areas that contain salty soil with high underground crusts. The areas are covered by halophyte plants such as Frankenia hirsuta. This species is a perennial plant from the Frankeniaceae family. They could absorb salt from soil and store it in their organs in order to reduce soil saltiness and restore slat of lands. Thus, in order to determine the percentage of sodium chloride of such species, sampling was taken in the flowering stage from two exclosure and grazing areas by six replications. Then, the percentage of Sodium Chloride (NaC1) was measured in the lab using the titration method. The statistical analyses and the comparisons of the means of the collected data were made by the use of T-test. The results showed significant difference for NaC1% of the phytomass of the species (P≤0.01). The average value of NaC1 was 2.13% and 1.37% for the exclosure and grazing area, respectively. In the other word, the highest and lowest values of NaC1% were obtained for exclosure and the grazing area, respectively. It was concluded that Frankenia hirsuta can take in the soil salt and by gathering or grazing, it could led to reduction of soil saltiness. Manuscript profile

Increasing the concentration of atmospheric carbon dioxide is the main factor for the climatic change having some harmful consequences for the human health while there is no considerable effort for decreasing this accelerated global problem, yet. Kermanshah province located in the west of Iran has about 1,200,000 ha rangeland which is dominated by Astragalus sppas the more frequent shrub beingable for the carbon sequestration and more than 80%, its biomass has a key role in the carbon sinking into the soil layers. In order to investigate the effects of topographic factors on carbon sequestration, this study was conducted in the Bazan rangeland of Kermanshah province as the representative site. This site is characterized by the indigenous vegetation of rangeland. The maps including topography, vegetation and date layers were digitized by GIS (Arc GIS 9.1). In each homogeneous area of representative site, two or three linear parallel 30 m intervals were randomly established along the slope length and plant sampling for biomass was doneusing a quadrate plot (1×1 m) with 10 m plotting intervals. In addition, the highest rate (118.68 kg/ha) of sequestered carbon was observed in the altitude of 1900-2100 m above sea level in the northern direction while the lowest stored rate (39.13 kg/ha) was found in 1100-1300 m in the southern direction. Manuscript profile

Ecotones are zones of gradual changes from an ecological system to another.Ecotones monitoring could be important to find out the reason for changes and limits. Inthis research satellite data were used to analyze the ecotone boundary in Fars steppicrangelands using IRS LISS III and Pan data of year 2006. The real vegetation map andecotones prepared through Geo-eye images from Google earth software and calibratedusing field study. Five soil line vegetation indices such as SAVI, MSAVI2, TSAVI,OSAVI and GESAVI from processed data were calculated. Each of these indices wasclassified by applying density slicing analysis method. Then the accuracy of producedmaps was audited with error matrix method. The results show OSAVI and SAVI had thehighest overall accuracy and kappa coefficient as 82.1% and 82% for overall accuracy and76% for Kappa coefficient, respectively. According to this research, soil line vegetationindices have intermediate accuracy for separation of arid rangelands ecotones in Iran withIRS data, although, OSAVI and SAVI perform better than the others. Manuscript profile