جستجوی مقالات مرتبط با کلیدواژه « کرنل مقاومت » در نشریات گروه « اکولوژی »

Despite the importance of central Iranian desert as a refuge for threatened carnivores, conservation strategies for these species have been hindered by scarcity of data on distribution and habitat connectivity. The present study aimed to 1) determine the ecogeographical variables affecting distribution of three fox species including sand fox (Vulpes rueppellii), Blandford’s fox (Vulpes cana), and red fox (Vulpes vulpes); 2) identify important core habitats and dispersal corridors of the three fox species; and 3) evaluate habitat patch importance to landscape connectivity. At first step, ensemble models were built for each species using three distribution algorithms and 12 ecogeographic variables. Distribution of the foxes was affected by annual precipitation, shrubland density, human settlement density and topographic roughness. In the next step, negative exponential function was used to convert ensemble distribution maps to resistance surfaces. Core patches and significant corridors were predicted using resistance kernel approach. Most of the habitat core patches were located in Protected Areas (PAs), which could be related to high landscape resistance outside the areas under protection. Finally, the importance of identified core patches was evaluated using graph network. The patch importance to connectivity was significantly correlated with core extent, mean of relative density of dispersing individuals and probability of occurrence in patch. Results showed that the habitat quality indices are more effective than habitat quantity in predicting landscape connectivity. The obtaining results suggest that effective conservation of carnivores demands for an integrated landscape management aiming at functional connectivity among habitat patches.

Long-term survival of Goitered gazelles in central Iran has been threatened because of isolation of existing populations and genetic threats. Effective management of these small and isolated populations needs to evaluate landscape connectivity among core habitat patches. In the present study, resistance surfaces were mapped as a function of twelve uncorrelated variables using species distribution algorithms. Given the limited empirical data of Goitered gazelle dispersal distances, we assessed different dispersal ability scenarios. Extent of core habitats, fracture zones, and dispersal corridors were identified using resistance kernel approach. Our finding showed that while gazelle population in Biduiyeh Protected Area has been isolated, there is relatively high dispersal rate among populations of Goitered gazelle in Mooteh National Park, Ghamishloo National Park, Kahyaz Protected Area, Kalmand-Bahadoran Protected Area and Kolah-Qazi National Park. Given the effect of roads and metropolises, functional connectivity between Kolah-Qazi and other populations is not possible. Based on genetic relationships and landscape connectivity results, we concluded that gazelle populations in Central Iran can be grouped into three separated subpopulations including 1- Biduiyeh P.A., 2-Kolah-Qazi N.P., and 3- gazelles in other protected areas. The obtained results show that integrated conservation management at landscape level need to be considered in maintaining gene flow among isolated and fragmented habitats.