University of Guilan Caspian Journal of Environmental Sciences 1735-3033 23 4 2025 10 01 Geochemical assessment of iron and manganese accumulation in woody and herbaceous vegetation of forest ecosystems, Northeast Kazakhstan 861 870 9203 10.22124/cjes.2025.9203 EN Sholpan Zhumadina S. Seifullin Kazakh Agrotechnical Research University, Astana, Kazakhstan Klara Izbastina S. Seifullin Kazakh Agrotechnical Research University, Astana, Kazakhstan Aiman Karabalayeva Astana International University, Astana, Kazakhstan Dinara Shakeneva Margulan University, Pavlodar, Kazakhstan Temirbay Daribay L.N. Gumilyov Eurasian National University, Astana, Kazakhstan Arailym Kurmanova L.N. Gumilyov Eurasian National University, Astana, Kazakhstan Latipa Kozhamzharova National Center for Professional development «Orleu», Astana, Kazakhstan Saule Mukhtubayeva Astana Botanical Garden” Branch of the Republican State Enterprise on the Right of Economic Management “Institute of Botany and Phytoinroduction, Astana, Kazakhstan Journal Article 2025 11 21 The article presents the results of a comprehensive geochemical assessment of the iron (Fe) and manganese (Mn) accumulation in woody and herbaceous vegetation of forest ecosystems in the North-East Kazakhstan: the Chaldai ribbon pine forest and the Bayanaul State National Nature Park (BSNP). The study covers four impact zones: protected, natural, anthropogenic and post-fire. A comparative analysis of element concentrations in plants and soils was carried out, and key biogeochemical coefficients were calculated: biotoxicity (PBE), accumulation (Kn), concentration (Kc) and background accumulation (Ko). The results showed that manganese plays a more active role in the biogeochemical cycle, especially in areas with high anthropogenic impact. Iron mainly accumulates in herbaceous forms, but does not reach a physiologically favorable Fe:Mn ratio (2:1), which may indicate stressful conditions for vegetation. In both forest areas, signs of aerotechnogenic pollution were established, while the level of pollution according to the integral indicator Zc was classified as weak. The obtained data confirm the sensitivity of plants to technogenic load and the need for regular environmental monitoring. https://cjes.guilan.ac.ir/article_9203_59d720987a31afd9d059bfd3c169cde2.pdf