1 2476-3128 1225 General Investigation of the Correlation between Microplastic Pollution and Potentially Toxic Elements in Caspian White Fish (Rutilus kutum) Haji Aghaei Ghaazi Mahalleh F. b Imanpour Namin J. c b Faculty of Natural Resource, University of Guilan, Sowmesara, Iran. c Faculty of Natural Resource, University of Guilan, Sowmesara, Iran. 1 8 2024 13 2 1 19 05 09 2024 15 12 2024 Abstract This research was conducted to investigate the statistical correlation between microplastic contamination and potentially toxic elements in Kutum populations (Rutilus kutum) at three sampling stations: Kiashar, Anzali and Astara, located along the Southwestern coast of the Caspian Sea. The results from analysis of 60 fish samples indicated that all samples were contaminated with microplastics. The highest mean abundance of microplastic, 53.75±35.50 (particles per fish), was observed at Anzali sampling station. The results of the elemental concentration analysis showed that Iron had the highest concentration, with a mean value of  23111 ± 5945.33  µg/kg at Anzali station. At Kiashar station, a significant negative correlation was observed between the abundance of microplastics and the concentrations of Cadmium and Nickel (rs˃-0.4, p˂0.05). At Astara station, a significant positive correlation was found between the abundance of microplastics and the concentrations of Arsenic and Nickel (rs˃0.4, p˂0.05). According to the comparison of elemental concentrations with FAO/WHO standards, only the concentration of Arsenic in fish from various stations exceeded the permissible limit. These findings indicate the complex interactions between microplastic contamination and elemental concentrations in Kutum (R. kutum) from the Caspian Sea, necessitating further research to evaluate the environmental impacts and the health of the Caspian Sea ecosystem.
1233 General Stock Status and Fisheries Reference Points for Common Carp (Cyprinus carpio) in the Aras Dam Reservoir, the West Azerbaijan Province Haghi Vayghan A. d Ghanbarzadeh M. e d Department of Ecology and Aquatic stocks management, Artemia and Aquaculture Research Institute, Urmia University. e Department of Natural Resources and Environmental Engineering, School of Agriculture, Shiraz University 1 8 2024 13 2 21 34 23 11 2024 21 12 2024 Abstract Aras Dam reservoir is the largest water source in the northwest of Iran in terms of exploitation of various aquatic species, but the information of its aquatic stocks is very limited. The purpose of this study was to determine the stock  status of common carp (Cyprinus carpio) in the Aras Dam reservoir using the latest version of catch-maximum sustainable yield (CMSY++) model. For this purpose, by using the CMSY++ model and the catch data from October 2013 to March 2022, and harvest limit and stock level of the common carp in the Aras Dam reservoir were estimated. The results indicate the poor condition of this species and the high fishing pressure on its stock. The length-weight relationship showed that growth pattern in common carp was homogeneous. In  general, the continuation of this trend and the failure to adjust the exploitation of this species stock, either legally or  illegally, will lead to the reduction and depletion of its stock.. This study, recommends to the decision makers for appropriate mangement of fishing especially illegal fishing, to pay attention to the allowed annual harvest limits, apply management policies and protection of  the nursery grounds of common carp in the Aras Dam reservoir.   1236 General Monitoring Zayandehroud River Ecosystem Health using Biological and Water Quality Indices Mohseni F. f Nemati Varnosfaderany M. g Soffianian A. h Fakheran S. i f Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran. g Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran. h Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran. i Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran. 1 8 2024 13 2 35 48 03 12 2024 20 01 2025 Abstract Zayandehroud is the water source for life in Central Iran, but it has become has turned into one of the most vulnerable ecosystem due to human disturbances. In this study, water quality and ecosystem health of Zayandehroud was evaluated in a segment of the river with permanent flow, from the Zayandehrud Regulating Dam to Pol-Kalleh. Water and benthic macroinvertebrate samples were collected from 11 stations during the summer of 2022. The Iranian Water Quality Index for Surface Water (IRWQISC), along with richness and diversity indices, as well as biological indices (BMWP and ASPT), were calculated. The findings revealed that the IRWQISC index categorizes water quality as moderate in most stations, with relatively good quality observed in only three stations. In contrast, the BMWP index denoted poor conditions, the ASPT index reflected severe to moderate pollution levels, and the Shannon diversity index also indicates severe to moderate pollution. The IRWQISC index was unable to accurately capture the effects of water flow interruption downstream of the Cham-Aseman diversion dam and its impact on the deterioration of water quality and overall river ecosystem health. However, the substantial decline in the richness index and biological indices at the Pol-Kalleh station highlights a significant ecological imbalance in the river ecosystem. 1228 General Monitoring the effects of land use and land cover changes on habitat quality in the Haraz watershed bazargan S. j Rajaei F. k Ahmadi Mirqaed F. l Gholipour M. m j Department of Environmental Sciences, Faculty of Science, University of Zanjan, Zanjan, Iran. k Department of Environmental Sciences, Faculty of Science, University of Zanjan, Zanjan, Iran. l Department of Environmental Sciences, Faculty of Marine and Environmental Sciences, University of Mazandaran, Babolsar, Iran. m , Department of Environment, Faculty of Natural Resources, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran. 1 8 2024 13 2 49 63 25 09 2024 05 02 2025 Habitat quality is a type of supporting ecosystem service that becomes fragile and vulnerable under the influence of land use changes. The aim of this study was to assess the quality of habitats in the Haraz watershed in Mazandaran province based on land use changes. The InVEST model was used to assess the quality of habitats in the study area. Land use images of three periods 2000, 2010 and 2020 were prepared using Landsat 7 and 8 satellite images in the Idrisi Selva environment. The results showed that the habitats located in the central part of the basin had the highest quality in the years considered, while the northern areas of the basin had the lowest quality. The rate of changes in habitat quality in the time periods 2000-2010, 2010-2020 and 2000-2020 indicated that habitat quality the hotspots are in the central regions and coldspots are in the northern parts. From 2000 to 2020, the coldspots of habitat quality have increased, while the hotspots have decreased. In general, from 2000 to 2020, habitat quality has decreased in 180,163 hectares and increased in 24,096 hectares of the region. Accordingly, it is necessary to adopt appropriate strategies in order to maintain the quality of its natural habitats in the development and conversion of land uses in the study area. 1237 General Analyzing the Effect of Urban Landscape Heterogeneity on Land Surface Temperature in Isfahan City Mahdiyeh A. n Lotfi A. o n Department of Natural Resources, Isfahan University of Technology, Isfahan o Department of Natural Resources, Isfahan University of Technology, Isfahan 1 8 2024 13 2 65 78 16 12 2024 16 02 2025 The rapid expansion of impervious surfaces in urban areas has caused significant environmental challenges, including shifts in temperature patterns and the formation of urban heat islands. Changes in land use patterns and structures profoundly influence the composition, configuration, and function of landscapes. This study analyzed changes in landscape structure and thermal zones in Isfahan city from 1992 to 2022. To achieve this, land surface temperature maps were generated, and landscape metrics were calculated to explore the relationship between land use changes and land surface temperature zones. The results revealed that bare lands with little to no vegetation dominate high-temperature zones, contributing significantly to the formation of urban heat islands. Furthermore, landscape metrics indicated that land use type significantly influences local temperature. However, the analysis of landscape metrics indicated that higher continuity between land uses and landscape structures does not necessarily result in lower temperatures. The key factor influencing temperature is the type of land use in the area. Therefore, it can be concluded that land surface temperature is influenced by combinations of land use. Given the importance of temperature adjustment in urban areas, the distribution and allocation of green spaces based on landscape principles play a critical role in urban thermal management. 1235 General Effect of Mycorrhizal Fungi on Mucilage Active Ingredient and Osmotic Regulators of Borage (Borago officinails L.) under Water Stress Rahimi A. p Jahanbin Sh. Salehi A. Faraji H. p Forests, Rangelands and Watershed Research Department, Kohgiluyeh-Boyerahmad Agriculture and Natural Resources Research and Education Center, AREEO, Yasouj, Iran. Department of Agriculture and Plant Breeding, Faculty of Agriculture, Yasouj University, Iran. Department of Agriculture and Plant Breeding, Faculty of Agriculture, Yasouj University, Iran. Department of Agriculture and Plant Breeding, Faculty of Agriculture, Yasouj University, Iran. 1 8 2024 13 2 79 92 01 12 2024 02 03 2025 Water stress is one of the most important factors affecting plant performance. Considering the potential effect of mycorrhizal fungi on modulating the effect of water stress on the performance of Borage , an experiment was conducted as split-plot in randomized complete block design. Water stress as the main factor in irrigation levels after 30, 60, 90, 120 and 150 mm water evaporation from evaporation pan class A and mycorrhiza fungi as sub-agent in levels of non-application, application of Glomus mosseae  and G. intraradices species were considered. For flower mucilage, the interaction of irrigation and mycorrhizal fungus was significant, and at the irrigation level of 120 and 150 mm, water evaporation increased the water stress and caused a decrease in flower mucilage. At the irrigation levels after 90, 120 and 150 mm of water evaporation, , the reduction of proline and soluble sugar of borage was observed after 60, 90, 120 and 150 mm of water evaporation in the presence of mycorrhizal fungus compared to the absence of fungus application. Based on the results, irrigation treatment is recommended after 90 mm of water evaporation and the application of mycorrhizal fungus G. mosseae.