Kazakhstan journal for oil & gas industryKazakhstan journal for oil & gas industry2707-42262957-806XKMG Engineering10886510.54859/kjogi108865Research ArticleGeo-ecological assessment of the Caspian Sea coastal zone in AktauDzhanaliyevaNurgul Sh.<p>PhD</p>nurgul.janaliyeva@yu.edu.kzhttps://orcid.org/0000-0002-9823-0255SerikbayevaAkmaral K.<p>Professor</p>serikbayeva.akmaral@yu.edu.kzhttps://orcid.org/0000-0001-8030-8934SeitkozhinaDamira A.damiraseit@gmail.comhttps://orcid.org/0009-0001-7535-9750AldakovaMadina D.m.aldakova@kmge.kzhttps://orcid.org/0009-0009-5737-7216SyrlybekkyzySamal<p>PhD, Professor</p>syrlybekkyzy.samal@yu.edu.kzhttps://orcid.org/0000-0002-0260-0611AltybayevaZhanssaule K.zhahsaule.altybayeva@yu.edu.kzhttps://orcid.org/0000-0002-8404-2157Yessenov UniversityBranch of KMG Engineering “KazNIPImunaigaz”24122025741011112204202527082025Copyright © 2025, Dzhanaliyeva N.S., Serikbayeva A.K., Seitkozhina D.A., Aldakova M.D., Syrlybekkyzy S., Altybayeva Z.K.2025<p><strong>Background:</strong> Pollutants, mainly heavy metals, accumulate in the coastal zone of the Caspian Sea and degrade local and regional ecosystems. Their presence affects living organisms and drives the transfer of toxic substances through food chains. Heavy metals impair green biomass at the molecular level by disrupting plant cell functions. The Normalized Difference Vegetation Index (NDVI), derived from satellite imagery, tracks changes in photosynthetic activity and plant vitality over time. Combining soil heavy metals analysis with NDVI enables monitoring at both ground and satellite levels.</p> <p><strong>Aim: </strong>The study aims to conduct integrated geo-ecological monitoring of soil and vegetation in the Caspian Sea coastal zone near Shapagatova village.</p> <p><strong>Materials and methods:</strong> Atomic absorption spectrometry was used to determine heavy metals in soil samples. Physico-chemical methods were applied to assess agrochemical properties of soils, and NDVI was calculated using standard procedures.</p> <p><strong>Results:</strong> A marked decrease in soil heavy metal concentrations, attributed to natural phytoremediation was observed. This process explains the loss of vegetation cover in the study area during the five-year period from 2019 to 2023.</p> <p><strong>Conclusion: </strong>The sharp decline in heavy metal concentrations is closely linked to changes in the NDVI index. Between 2019 and 2021, when heavy metal levels exceeded maximum allowable concentrations, plants showed a reduced photosynthetic response, with the lowest values recorded in 2021. This reflects the toxic impact on vegetation, while the concurrent drop in metal concentrations that year is attributed to plant uptake. By 2023, with heavy metal levels decreasing more than twentyfold, NDVI values increased significantly, indicating recovery of plant biomass in the study area.</p>monitoringheavy metalsremote sensingNDVI vegetation indexMangistau regionмониторингауыр металдарқашықтықтан зондтауNDVI вегетациялық индексіМаңғыстау облысымониторингтяжёлые металлыдистанционное зондированиевегетационный индекс NDVIМангистауская область1.Ramazanova E, Bahetnur Y, Yessenbayeva K, et al. Spatiotemporal evaluation of water quality and risk assessment of heavy metals in the northern Caspian Sea bounded by Kazakhstan. Marine Pollution Bulletin. 2022;181:113879. doi: 10.1016/j.marpolbul.2022.113879.2.El-Sharkawy M, Alotaibi MO, Li J, et al. Heavy Metal Pollution in Coastal Environments: Ecological Implications and Management Strategies: A Review. Sustainability. 2025;17(2):701. doi: 10.3390/su17020701.3.Udofia UU, Joseph AP. 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