Zohreh Talebi - Department of Water Engineering and Management, Tarbiat Modares University, Tehran, Iran
Seyyed Ali Ayyoubzadeh - Department of Water Engineering and Management, Tarbiat Modares University, Tehran, Iran
Hossein Mostafavi - Department of Biodiversity and Ecosystem Management, Environmental Sciences Research Institute, Shahid Beheshti University, Tehran, Iran
Mohammad Mahdi Hosseinzadeh - Department of Physical Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

River ecosystems face numerous human pressures that can lead to certain impacts on the environment. However, there is limited information available regarding the prevalence, spatial patterns, mutual impacts, and simultaneous occurrences of these pressures. In this study, we aimed to identify and assess various types of human pressures at different scales within the Talar River catchment. In this regard, a total of ۴۳ sites within the Talar River catchment were selected for investigation. We employed a comprehensive approach by selecting ۳۰ key indicators that represent major human pressures on river ecosystems. These indicators were combined to create a pressure index. The findings revealed that ۹۳% of the studied sites experienced land use pressure, indicating significant human modification in those areas. Additionally, ۶۹% of the sites were subjected to connectivity pressure, ۸۸% to morphological pressure, ۸۶% to water quality pressure, and ۴۱% finally exhibited hydrological pressure. Importantly, our analysis also revealed complex interactions between multiple human pressures. Approximately ۸.۴% of the sites were affected by two distinct human pressures, while ۲.۳% experienced three overlapping pressures. Moreover, an overwhelming majority (۹۲%) of the sites were impacted by combinations of more than three human pressures, emphasizing the cumulative impacts of all pressures. These findings underscore the need for comprehensive and systematic consideration of multiple factors when undertaking integrated river basin management and restoration efforts. In other words, effective management and restoration strategies should account for the different scales within the catchment and address the specific combinations of human pressures present.

river assessment, anthropogenic pressures, cumulative pressures, Integrated river basin management, Restoration