عنوان مقاله [English]
Arid and semi-arid ecosystems due to lack of diversity in their structures and variables are prone to rapid degradation of vegetation composition in response to environmental changes. Processes and disturbances with subtle changes of the soil current patterns can result in the emergence of large scale dynamics across landscape. Occurrence of diffuse heterogeneities in soil attributes and consequently variations in vegetation patches can be a sign of the emergence of alternative stable states (as uniform vegetated and barren states) in arid ecosystems. Such contrast in distributions of vegetation and soil patterns may result in activation of positive feedbacks between soil-vegetation which have main role on the arid landscapes dynamics. Increasing positive feedbacks with decreasing system’s resilience lead to irreversible transformation onto degraded states. Since information on the soil-vegetation feedbacks can promote our understanding of how arid landscape responses to external stresses, in this paper has been noted impacts of positive feedbacks in evolution trends of arid ecosystems. Here has been shown that how the emergence of heterogeneities on the landscape dominant soil with occurrence of positive feedbacks between soil-vegetation can result in decreasing resilience and intensification of desertification trends.