Carbon sequestration in rangeland ecosystems has been identified as a suitable strategy to offset greenhouse gas emissions that information of carbon sequestration hotspots is a good tool to improve rangeland management. Objectives for this study were to assessment potential carbon sequestration in various rangeland types, to identify carbon sequestration hotspots and to study the effective factor on hotspots in semiarid rangeland of Kerman province. The content of above and underground biomass and litter carbon by Ash method and soil carbon by Walcky-Black method were determined in 300 plots 2m×2m that scattered randomly in rangeland types. Results showed that rangeland types had significant effect on carbon sequestration as Zygophyllum eurypterum-Artemisia sieberi, Artemisia sieberi-Pteropyrum aucheri, Astragalus microcephalus –Stipa barbata, Artemisa sieberi and Artemisia sieberi- Salsola brachiata respectively with 65.84, 53.92, 43.32, 33.17 and 24.77 (T/ha) contained from the highest to the lowest carbon sequestration. Carbon sequestration hotspots and coldspots were mapped by using hotspots analysis. Zygophyllum eurypterum-Artemisia sieberi and small parts of both types Artemisia sieberi-Pteropyrum aucheri and Astragalus microcephalus–Stipa barbata with 65.34 (T/ha) were carbon sequestration hotspots. Majority of Artemisia sieberi-Salsola brachiata and small parts of Artemisa sieberi with 23.78 (T/ha) included carbon sequestration coldspots. PCA analysis also showed that life form, clay and vegetation cover were the most important factors influencing on the hotspots. It was concluded although rangeland types demined with Phanerophyte species had a greater probability of being identified as carbon sequestration hotspots, soil characters also play effective role to stock carbon in semiarid rangeland ecosystems. Manuscript profile

Rangeland health assessment provides qualitative information on ecosystemattributes. We examined changes in rangeland health in the Zagros semi-arid rangelands ofIran at fixed sites between 2001 and 2011, over the 10-year period. The rangelandfragments significantly declines in the quality of the vegetation, and changes in plantspecies were driven largely by seasonality, and to a lesser extent, amount of rainfall. Threeindices of rangelands health (composition, function and stability) developed using sitebasedvegetation and landscape data. The results indicated that the majority of sites hadintermediate values of the three indices, and few sites had either very low or very highvalues. The indices of composition and function were strongly correlated with thesubjective ratings applied to each site at each measurement period. The results of this studyhighlight the difficulty of detecting change over extensive areas of rangeland, and ofseparating management induced effects from climatic effects in an environment whichexperiences wide spatial and temporal variation in rainfall. Results showed that soil surfaceresistance decrease and water flow pattern degradation were the most important causes inrangeland health decrease. Although, Chalghafa rangelands have enough rain falls tosupport habitation, humans had degraded the landscape. Moderate grazing is the best wayto use the grazing land without severe reduction in abundance and biomass of species. Manuscript profile

To reach the desirable ecosystem management, determining the animal dietselection, which is one of the components of rangeland ecosystem, is important. Therefore, inorder to determine the grazing behavior and diet selection of sheep and goat, the uplandrangeland of northern part of Alborz was selected. In this study, the first weeks of July andAugust of 2009 were chosen for the grazing period of the animals. Range value and rangetrend method and the help of trend balance determined the range conditions and plantcompositions in these two periods. Using the bite counting method, the grazing behavior ofanimals (sheep and goat) was observed from 0.5-2m via half an hour focus on each one andcompleting hundred records. Data collected and analyzed through the analysis of variance.Results showed that the bite counting method is a useful tool for determining the dietselection of sheep and goat. The animals have selected different layers of vegetation cover;therefore, range conditions have an effective role on the diet selection of animals within agrazing period. It has also shown that consumption rate was different in daily grazing inwhich sheep preferred to graze the forbs and goat browsed the bushy tree and shrub species ifthe grazing conditions were normal without any tension. Knowledge of the conditions ofanimals’ diet selection in each area could have an effective role on the production ofrehabilitation and development programs. Manuscript profile

The main objective of an ecosystem sustainable management is to preserve itscapacity to respond and adapt to current disturbances and/or future changes, and maintain theprovision of environmental goods and services. Two very important properties linked to thisobjective are the ecosystem resilience and resistance to disturbance factors. The objective ofthis paper is to recommend conceptual modifications to the integration of key ecologicalconcepts such as dynamic equilibrium, resistance and resilience to the ‘State and TransitionModel’ (STM) in order to apply them in a more feasible way for rangeland management.Ecological resilience describes the amount of change or disruption required to transform asystem from being maintained by one set of mutually reinforcing processes and structures to adifferent set of processes and structures. STMs integrated to concepts of structure, functionand energy provides greater opportunities to incorporate adaptive management, more accurateforecasts and a better and easier comparison between rangeland ecosystem types thantraditional STMs. We propose to enhance the STM considering four principal axes (ecosystemfunctions and/or processes, natural disturbances and/or negative management activities,required energy to return to the previous state, and structural ecosystem changes and transitiontime) also simultaneously, to compare the “robust” ecosystem to “fragile” ecosystem. Therecommended modifications enable STMs to identify a broader range of variables to anticipateand identify conditions which determine state resilience to better inform ecosystem managersof risk and restoration options. Manuscript profile