جستجوی مقالات مرتبط با کلیدواژه « مدلسازی توزیع گونه » در نشریات گروه « محیط زیست »

Iran stands out as one of the world's biodiversity hotspots. Simultaneously, river fish species within the country face imminent threats from various human activities. Climate change, among other challenges, poses a significant risk to the biodiversity of Iran. Consequently, there is a critical need to anticipate potential habitat changes for freshwater fish species in response to climate change. This study focuses on evaluating the impact of climate change on the habitats of the Song fish, a species with economic value and conservation significance. The Song fish is currently classified as Vulnerable (VU) by the International Union for Conservation of Nature (IUCN), making the examination of climate change effects crucial for the future population of this species.

This study employs the MaxEnt model to predict the spatial distribution of the Song fish at two different time scales (2050 and 2080 AD) under both optimistic (RCP2.6) and pessimistic (RCP8.5) climate scenarios. The R software environment was used for the analysis. Environmental variables, including slope, annual temperature range, flow accumulation, annual precipitation, annual mean temperature, and upstream drainage area, were considered. The data related to the observations of this species have been collected from sampling and various library sources. Modeling performance in predicting species distribution has also been evaluated by the AUC (Area Under the Curve) criterion.

The model demonstrated excellent performance in predicting species distribution, as indicated by the high AUC (Area Under the Curve) criterion value of 0.989. Among the environmental variables, annual average temperature and slope emerge were the most influential factors in determining the distribution of the Song fish. Furthermore, the study revealed a projected decrease in the distribution range of this species under both optimistic and pessimistic scenarios for 2050 and 2080.

To safeguard the Song fish, it is imperative for managers to identify and implement appropriate measures. These measures should aim to mitigate the effects of climate change and alleviate threats associated with these changes.

Species separation based on phylogenetic results can be supported by modeling whose input is habitat data. In the present study, two sister taxa that have been separated based on molecular documentation have been examined in terms of habitat influencing factors that may have been involved in this separation, as well as in terms of past and future historical distribution.

in order to model the distribution of species, Bio-Climatic variables from CHESLA database with variables of DEM, Slope and vegetation index were examined as habitat data to input the model. Also, the presence points of the species were filtered after collection in the reproductive interval and added to the models as train data. In this study, sdm package including eight models (GLM،GAM ، BRT، RF،CART ،SVM ، MaxEnt و MARS) in R software environment was used for modeling. Modeling of species distribution from the last glacial period to 2050 was also performed.

the results showed the ecological niche separation of the species under the influence of environmental variables. . Also, according to the results, in 2050, suitability habitats for Embriza bruniceps species will be limited to the northeast of the country and for Embriza melanocephala species, suitability will be limited to areas in the south of Alborz mountain range, northwest and west of Iran.

According to the results the area of suitable habitats for Embriza melanocephala species in the west has been less than today, which according to studies,