مجله بوم شناسی کاربردی
پیاپی 46 (زمستان 1402)

Riverine ecosystems and aquatic animals have suffered many pressures due to the increase of human industrial activities and subsequent climate changes. In the present study, changes in the distribution range of the bream fish (Abramis brama) inhabiting the rivers of the southern Caspian Sea basin in the years 2050 and 2080 under optimistic and pessimistic climate scenarios were assessed by using the MaxEnt model. This study utilized datasets collected by the authors and various scientific resources available over 50 years (1970-2020). According to the receiver operating characteristics curve, and area under curve (AUC), the model performance in predicting species distribution was excellent (AUC = 0.947). Furthermore, modeling results indicated a significant likely decrease in the distribution of this species under both optimistic and pessimistic scenarios, in both periods of 2050 and 2080, with the highest predicted reduction percentage of 98.71% under the pessimistic scenario in 2080. Given the importance of the bream fish in the food chain and its positive impact on the economy and livelihoods of local communities, conservation efforts such as preventing overfishing, developing conservation strategies to cope with future events, and striving to reduce climate change accelerators are recommended for the protection of this valuable species.

Conservation of habitat corridors is important in order to reduce the impacts of habitat fragmentation on wildlife. The present study aimed to identify the potential habitat corridors between habitat patches of this family using factorial least-cost path analysis and UNICOR software. By overlaying the habitat corridors of the mustelidae family, the study examined the coverage of the habitat corridor hotspots with the conservation areas designated by the Department of Environment of Iran, as well as the road density within these hotspots. The results revealed that the largest habitat corridors were associated with weasel, stone marten, and marbled polecat species. Habitat corridor hotspots of the mustelid species are mainly located in the Zagros and Alborz mountains. The coverage of habitat corridor hotspots with conservation areas was less than 25%, and the road density was about 50 m/km2. It is necessary to consider the habitat corridor hotspots of the mustelids when creating new conservation areas and  implementing measures to minimize road-related losses in these hotspots. The conservation of the mustelidae family as mesocarnivorous species ensures the survival of wildlife food webs and contributes to the sustainability of Iran's biodiversity.

Wetlands are one of the most unique ecosystems on earth, and their destruction is a result of direct and indirect human interactions. This study examines the abundance and diversity of birds in the Bandalikhan wetland and their relationship with water fluctuations and drought over a 10-year period (2012-2022). Bird census data was collected, and species richness and diversity indices were calculated. The changes in the water level were determined using the normalized water difference index (NDWI) and Landsat images. Rainfall, temperature, and drought index were extracted from meteorological records, and their correlation was analyzed. Results showed that common teal (Anas crecca) and mallard (Anas platyrhynchos) were the most abundant birds, and the highest values of species diversity and richness indices were obtained for the wettest year (2019). Linear regression revealed a positive and significant relationship between NDWI and the number of bird species (R2 = 0.72) and abundance (R2 = 0.74) of birds. A significant relationship was found between the drought index and the number of species (R2 = 0.62). To conserve the diversity and abundance of wetland birds, it is necessary to prevent large fluctuations in the water level, as this reduces the habitat suitability for birds.

Non-invasive sampling methods, such as scat sampling, have facilitated genetic studies for conservation genetics researchers, however, the quality and quantity of extracted DNA have always been the main issues with these methods. In the current study, the genetic variation and population structure of wild sheep (Ovis gmelini) in Bamou National Park (Fars, Iran) were evaluated using the swabbing technique and eight microsatellites. The sampling method used showed high efficiency in genotyping individuals and can be considered  for use with other species. Expected and observed heterozygosity ranged from 0.502 to 0.943 and 0.950 to 1.00, respectively, and the mean allele richness was 8.87, indicating considerable genetic variation in the population. In addition, inbreeding coefficient across all loci was 0.052. There was no evidence of a bottleneck in the population in the recent past. Despite the high level of genetic variation, the lack of gene flow between populations, and global threats such as climate change, highlight the necessity of implementing reintroduction programs to maintain the evolutionary potential of the species.

The present survey was conducted to investigate the ecological distribution range of woody species and the most important factors affecting their distribution in the Zagros forests of Ilam province. physical and chemical characteristics of soil, as well as topographical factors, were assessed in 109 circular sampling plots with an area of 500 m2 n four forest areas with an altitude range of 800-2400 m. The vertical distance of the plots on the slope aspect was 100 m, and the distance of the sampling routes varied from 500-1000 m. ecological distribution range index was calculated based on the most important factors affecting species distribution. Based on the Principal Component Analysis (PCA), the most significant factors include: the percentage of theclay, Potassium, nitrogen, carbon, sand, phosphorus, and altitude. species such as Amygdalus orientalis, Lonicera nummularifolia, Daphne mucronata and Cerasus mahaleb and Acer monspessulsnum were found at hight altitudes with the highest levels of carbon, nitrogen, potassium and phosphorus. In addition, Quercus brantii along with Acer monspessulanum and Daphne mucronata showed the highest ecological distribution range while Pistacia atlantica, Amygdalus arabica and Amygdalus orientalis species respectively has the lowest values. Overal, results indicate that topography and soil factors play an important role in the distribution of woody species in the studied areas.