جستجوی مقالات مرتبط با کلیدواژه « مدل سازی پراکنش گونه ای » در نشریات گروه « محیط زیست »

Habitat loss is the main threat to the endangered populations of wildlife and anthropogenic climate change is expected to exacerbate this. Here, we identify suitable habitats of wild sheep in Lorestan Province and how these habitats are affected by the climate change scenarios, in order to address conservation and management efforts. The ensemble modeling based on six species distribution models (SDMs) was used to predict current and future distributions, in response to the changing climate. Our models predicted that 7.4% of the 28,294 km2 study area is currently suitable habitat for the species. Land cover, temperature seasonality (bio4), distance to spring, human footprint and distance to escape terrain made the highest contribution (80%) to the distribution model performance. Findings show that about 62.14 (RCP4.5) to 76.97% (RCP8.5) of present suitable habitat would be lost by 2050 due to climate change under four future representative concentration pathways within BCC-CSM1-1 general circulation model. In contrast, habitat gains observed for models were 5.89 (RCP8.5) to 17.01% (RCP4.5). Our findings could provide useful information for conservation planning to protect and restore wild sheep populations.

Over the last few decades, human threats have imposed widespread negative impacts on populations of ungulates in Iran. While, climate change may also additionally increase vulnerability of the ungulates through changing current environmental conditions in future. In this study, impact of future climate change on distribution of two vulnerable ungulates of wild sheep (Ovis sp) and wild goat (Capra aegagrus) and changes in their current distribution along altitudinal and latitudinal gradients were investigated. Future predictions were made using an ensemble modelling approach and climate data prepared by five global circulation models based on RCP 8.5. Future range shifts by 2070 were also estimated by calculating the difference between mean elevation and difference of geographic distance between centroids of current and future distribution ranges, respectively. Results indicated that as a result of climate change, more than 68% and 75% of suitable habitats for wild sheep and wild goat may become lost by 2070, respectively mostly across low elevations of southern (south Khorasan, Yazd and Fars) and central (east of Isfahan) parts. Climate change also resulted in proportions of currently unsuitable habitats to become suitable expansion of which was limited to northern part (Semnan province). Result of evaluations also revealed that current distributions of wild sheep and wild goat may change as much as 27 and 150 m and; 167 and 124 km along elevational and latitudinal gradients, respectively.

Pheasant (Phasianus colchicus) is one of the protected birds occupying a wide range of habitats in northern parts of Iran. Successful management of this species demands information on its habitat requirements. In this study, habitat suitability for pheasant was assessed using ecological niche modeling across Golestan Province. For this purpose, 15 environmental variables presumably participating in constraining the large-scale niche dimensions of pheasant were used to model the ecological niche and distribution of the species using a maximum entropy algorithm. Results indicated that model predictions were statistically significantly better than random expectations. Model predictions identified three separate regions of potential pheasant distribution, in the western, central, and eastern parts of the province, and as well a small area in the northwest, but pheasant distribution is largely limited to the southern part of the province in forested areas and their surrounding habitats. Generally, 8.6%, 28.1%, and 63.3% of the province were categorized as potentially suitability at high, moderate, and low levels, respectively. The variables “distance to forest” and “precipitation seasonality” as most relevant determinants of pheasant distribution.