Freshwater ecosystems are increasingly affected by anthropogenic stressors, necessitating the assessment of sensitive biomarkers of sublethal impact. This study assessed the seasonal variability of oxidative stress parameters in the amphipod Gammarus lacustris from three tributaries of Lake Sevan (Armenia)—the Gavaraget, Karchagbyur, and Argichi Rivers—with contrasting hydrophysical and hydrochemical conditions. During 2022–2024, lipid peroxidation (MDA), antioxidant enzymes (CAT, SOD, GR, and GST), and glutathione (GSH) were measured in specimens collected in May, July, and October and related to temperature, dissolved oxygen, nutrients, major ions, and trace elements. Biomarker levels generally increased from spring to summer and declined in autumn, following temperature and photoperiod patterns. Statistically significant seasonal dynamics were most consistent in the Karchaghbyur River, while, in the Gavaraget and Argichi Rivers, they varied by biomarker and year. Amphipods from the Gavaraget River exhibited consistently elevated levels of oxidative stress biomarkers, consistent with elevated nutrient concentrations and stronger anthropogenic impacts. A short-term increase in all biomarkers in the Argichi River in 2023 indicated episodic acute stress. Overall, the response of oxidative stress biomarkers in G. lacustris reflected both the natural seasonal variability and spatial differences in environmental pressure, confirming their potential as a tool for monitoring Lake Sevan’s tributaries.

River ecosystems are increasingly vulnerable to intensified human pressures associated with population growth and rising living standards, leading to structural changes and altered ecosystem service (ES) provision. The lower course of the Hrazdan River (Armenia) exemplifies these impacts, as it flows through Yerevan, the capital city, and receives substantial inputs of largely untreated wastewater. To assess resulting changes in ES, this study applies a multi‐method approach combining field‐based ecological assessments with social survey research. This integrated framework enables the comparison of actual ES flows with stakeholder perceptions, capturing both biophysical conditions and societal values. Results reveal a marked discrepancy between perceived and actual ES provision. While regulating and maintenance services are relatively highly prioritised by stakeholders, many essential ecosystem functions remain poorly understood, indicating significant knowledge gaps and limited public engagement. At the same time, the availability and quality of key services are severely degraded, contributing to tensions between stakeholders and decision‐makers. These findings point to persistent management challenges, including mismatches between top–down governance and bottom–up engagement. The study highlights the importance of integrating ecological data with social perspectives to support more effective, inclusive and conservation‐oriented management strategies for heavily impacted river systems.

С 2011 г. ведутся работы по улучшению системы управления водными ресурсами Армении, в результате которых территория республики разделена на шесть территорий управления речными бассейнами и основана государственная система гидробиологического мониторинга, требующая регулярного исследования экологического состояния поверхностных водных объектов. Данная работа посвящена оценке изменений в сообществе донных макробеспозвоночных в бассейне реки Ехегис спустя десятилетие после первоначальных исследований. Результаты показывают более высокое таксономическое разнообразие по сравнению с 2012 г., однако существенных изменений в общем экологическом состоянии не выявлено. Это подтверждает возможность дальнейшего использования упрощенного мультиметрического индекса, разработанного для управления Араратским речным бассейном. В то же время необходимы дополнительные исследования видового состава донных макробеспозвоночных для повышения эффективности индекса. Due to initiated in 2011 improvements in the water management system of Armenia, six Basin Management Areas were created and hydrobiological monitoring was introduced. It requires regular investigations of ecological status of surface water bodies. The current research aims to study the changes in the assemblage of benthic macroinvertebrates in the basin of the Yeghegis River ten years after the baseline studies. The results show higher taxonomic diversity for this basin in comparison with 2012. However, significant changes in its overall ecological status have not been revealed. This proves the assumption that existing multimetric index can be still used for the Ararat Basin Management Area, but further investigations of species structure of benthic macroinvertebrates are necessary to improve its performance.

Armenia is a mountain country with medium to high baseline water stress. Water reservoirs established mostly in the Soviet era either have hydropower or irrigation purposes but were never designed for multipurpose use. River Hrazdan was regulated by three single-purpose reservoirs covering a range of altitudes and landscapes. The aim of the present study is to conduct a non-monetary assessment of the ecosystem services of reservoirs and to analyze their potential. We hypothesize that current water resource management practices in Armenia do not adequately account for the flow of ecosystem services. We used macrophytes, microorganisms, phytoplankton, and hydrochemical parameters both for the evaluation of ecosystem services and for the assessment of ecosystem structure and functions. Since reservoirs are primarily used for energy generation, water supply, and flood protection, these services were not considered in the present study. Instead, we assessed ten benefits provided by the reservoirs. The results of investigation showed that three reservoirs exhibit considerable ecological and socio-economic value through multiple ecosystem services. While most water quality parameters fall within permissible limits for irrigation, certain elements exceed recommended thresholds, highlighting the need for monitoring and management to prevent potential soil and plant health impacts. Phytoplankton and macrophyte communities are contributing to oxygen production, nutrient cycling, and habitat provision for aquatic fauna. Plants also significantly contribute in nutrient uptake, pollutant removal, and sediment stabilization. Ornamental macrophytes further provide cultural ecosystem services, supporting recreational, aesthetic, and educational functions, while also performing ecological roles such as phytoremediation and carbon sequestration.

С 2011 г. ведутся работы по улучшению системы управления водными ресурсами Армении, в результате которых территория республики разделена на шесть территорий управления речными бассейнами и основана государственная система гидробиологического мониторинга, требующая регулярного исследования экологического состояния поверхностных водных объектов. Данная работа посвящена оценке изменений в сообществе донных макробеспозвоночных в бассейне реки Ехегис спустя десятилетие после первоначальных исследований. Результаты показывают более высокое таксономическое разнообразие по сравнению с 2012 г., однако существенных изменений в общем экологическом состоянии не выявлено. Это подтверждает возможность дальнейшего использования упрощенного мультиметрического индекса, разработанного для управления Араратским речным бассейном. В то же время необходимы дополнительные исследования видового состава донных макробеспозвоночных для повышения эффективности индекса. Due to initiated in 2011 improvements in the water management system of Armenia, six Basin Management Areas were created and hydrobiological monitoring was introduced. It requires regular investigations of ecological status of surface water bodies. The current research aims to study the changes in the assemblage of benthic macroinvertebrates in the basin of the Yeghegis River ten years after the baseline studies. The results show higher taxonomic diversity for this basin in comparison with 2012. However, significant changes in its overall ecological status have not been revealed. This proves the assumption that existing multimetric index can be still used for the Ararat Basin Management Area, but further investigations of species structure of benthic macroinvertebrates are necessary to improve its performance.