Habitat classification of the Khortytsia Island floodplain after the Kahovka catastrophe using the European Nature Information System (EUNIS)
Abstract
This study aimed to analyse, categorise, and interpret the habitat diversity of Khortytsia Island's floodplain in Ukraine. It e m ployed the European Nature Information System H abitat C lassification alongside an integrated approach that incorporated geobotanical, geomorphological, bioindication, and remote sensing methods. A total of 876 vegetation relevés from 2024–2025 were examined. Plant communities were initially grouped through Two-Way Indicator Species Analysis, with diagnostic species identified based on fidelity values and indicator analysis. These floristic groups were then assigned to habitat types by comparing them with the system's key navigation, factsheets, formal definitions, and official crosswalks. To understand the main factors driving habitat differentiation, analyses included geomorphological variables, ecological indicator values, plant strategy analysis, M ultivariate A nalysis of V ariance, C anonical C orrespondence A nalysis, and P artial C anonical C orrespondence A nalysis. Habitat mapping using remote sensing was conducted to analyse spatial and temporal changes from 2022 to 2025. Ten terrestrial habitat types and two water-associated types were distinguished. The terrestrial habitats comprised pioneer sandy vegetation, drawdown-shore communities, riverine willow scrub, humid tall-herb assemblages, reed canary-grass beds, willow gallery forests, mixed poplar riparian forests, floodplain oak forests, and sandy steppes. Habitat differentiation was primarily influenced by geomo r phology ( especially elevation, topographic position, and wetness ) distinguishing low alluvial depressions, wet floodplain zones, and elevated sandy terraces. Ecological indicator values revealed that edaphic moisture, air humidity, soil pH, and nitrogen levels were the strongest predictors of habitat differences. These gradients mainly reflected hydrological, trophic, and substrate-chemical variations, with plant strategies indicating distinct traits related to competition, stress tolerance, and disturbance adapt a tion. Spatial analysis showed a shift from a relatively stable floodplain pattern in 2022 to a highly dynamic mosaic in 2024–2025, driven by drainage, substrate exposure, and faster succession. The findings demonstrate that the European Nature Information System offers a robust framework for interpreting habitat changes after disturbances, supports comparable biodiversity asses s ments globally, and provides vital information for conservation planning in the fo rmer Ka hovka floodplain. The study unde r scores the conservation potential of this area amidst ongoing ecological reorganisation.References
Castañeda, C., Gracia, F. J., Conesa, J. A., & Latorre, B. (2020). Geomorphological control of habitat distribution in an intermittent shallow saline lake, Gallocanta Lake, NE Spain. Science of The Total Environment, 726, 138601.
Chapman, M., Jung, M., Leclère, D., Boettiger, C., Augustynczik, A. L. D., Gusti, M., Ringwald, L., & Visconti, P. (2025). Meeting European Union biodiversity targets under future land-use demands. Nature Ecology and Evolution, 9(5), 810–821.
Chhetri, S., Ruangpan, L., Abebe, Y. A., Torres, A. S., & Vojinovic, Z. (2024). Review of environmental benefits and development of methodology for EUNIS habitat changes from nature-based solutions: Application to Denmark and the Netherlands. Ecological Indicators, 165, 112189.
Chusova, O. O., Shyriaieva, D. V., Budzhak, V. V., Chorney, I. I., Dziuba, T. P., Iemelianova, S. M., Kucher, O. O., Moysiyenko, I. I., Tokariuk, A. I., Vasheniak, I. A., Vynokurov, D. S., Boyko, M. F., Khodosovtsev, O. Y., & Kuzemko, K. A. A. (2022). Protected species in the grassland habitats of Ukraine. Ukrainian Botanical Journal, 79(5), 290–307.
Chytrý, M., Řezníčková, M., Novotný, P., Holubová, D., Preislerová, Z., Attorre, F., Biurrun, I., Blažek, P., Bonari, G., Borovyk, D., Čeplová, N., Danihelka, J., Davydov, D., Dřevojan, P., Fahs, N., Guarino, R., Güler, B., Hennekens, S. M., Hrivnák, R., & Axmanová, I. (2024). FloraVeg.EU – An online database of European vegetation, habitats and flora. Applied Vegetation Science, 27(3), e12798.
Chytrý, M., Tichý, L., Hennekens, S. M., Knollová, I., Janssen, J. A. M., Rodwell, J. S., Peterka, T., Marcenò, C., Landucci, F., Danihelka, J., Hájek, M., Dengler, J., Novák, P., Zukal, D., Jiménez‐Alfaro, B., Mucina, L., Abdulhak, S., Aćić, S., Agrillo, E., Schaminée, J. H. J. (2020). EUNIS habitat classification: Expert system, characteristic species combinations and distribution maps of European habitats. Applied Vegetation Science, 23(4), 648–675.
Dengler, J., Jansen, F., Chusova, O., Hüllbusch, E., Nobis, M. P., Van Meerbeek, K., Axmanová, I., Bruun, H. H., Chytrý, M., Guarino, R., Karrer, G., Moeys, K., Raus, T., Steinbauer, M. J., Tichý, L., Tyler, T., Batsatsashvili, K., Bita-Nicolae, C., Didukh, Y., & Gillet, F. (2023). Ecological indicator values for Europe (EIVE) 1.0. Vegetation Classification and Survey, 4, 7–29.
Didukh, Y. P. (2011). The ecological scales for the species of Ukrainian flora and their use in synphytoindication. Phytosociocenter, Kyiv.
Egozcue, J. J., Pawlowsky-Glahn, V., Mateu-Figueras, G., & Barceló-Vidal, C. (2003). Isometric logratio transformations for compositional data analysis. Mathematical Geology, 35(3), 279–300.
Erdős, L., Bede-Fazekas, Á., Bátori, Z., Berg, C., Kröel-Dulay, G., Magnes, M., Sengl, P., Tölgyesi, C., Török, P., & Zinnen, J. (2022). Species-based indicators to assess habitat degradation: Comparing the conceptual, methodological, and ecological relationships between hemeroby and naturalness values. Ecological Indicators, 136, 108707.
Frank, D., & Klotz, S. (1990). Biologisch-ökologische Daten zur Flora der DDR. In: Wissenschaftliche Beiträge der Martin-Luther-Universität Halle-Wittenberg. Martin-Luther-Universität, Halle-Wittenberg, Halle.
Galparsoro, I., Connor, D. W., Borja, Á., Aish, A., Amorim, P., Bajjouk, T., Chambers, C., Coggan, R., Dirberg, G., Ellwood, H., Evans, D., Goodin, K. L., Grehan, A., Haldin, J., Howell, K., Jenkins, C., Michez, N., Mo, G., Buhl-Mortensen, P., & Vasquez, M. (2012). Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs. Marine Pollution Bulletin, 64(12), 2630–2638.
Gleick, P., Vyshnevskyi, V., & Shevchuk, S. (2023). Rivers and water systems as weapons and casualties of the Russia‐Ukraine war. Earth’s Future, 11(10), e2023EF003910.
Goncharenko, I. V. (2017). Fitoindykaciya antropogennogo navantazhennya [Phytoindication of anthropogenic factor]. Serednyak T. K., Dnipro (in Ukranian).
Grime, J. P. (1974). Vegetation classification by reference to strategies. Nature, 250(5461), 26–31.
Hryhorczuk, D., Levy, B. S., Prodanchuk, M., Kravchuk, O., Bubalo, N., Hryhorczuk, A., & Erickson, T. B. (2024). The environmental health impacts of Russia’s war on Ukraine. Journal of Occupational Medicine and Toxicology, 19, 1.
Kuzemko, A. A., Prylutskyi, O. V., Kolomytsev, G. O., Didukh, Y. P., Moysiyenko, I. I., Borsukevych, L. M., Chusova, O. O., & Khodosovtsev, O. Y. (2025). Initial stages of revegetation at the bottom of the drained Kakhovka Reservoir (Ukraine): Synthesis of field surveys and remote sensing. Ukrainian Botanical Journal, 82(5), 488–501.
Kvach, Y., Stepien, C. A., Minicheva, G. G., & Tkachenko, P. (2025). Biodiversity effects of the Russia–Ukraine War and the Kakhovka Dam destruction: ecological consequences and predictions for marine, estuarine, and freshwater communities in the northern Black Sea. Ecological Processes, 14(1), 22.
Lindsay, J. B. (2016). Whitebox GAT: A case study in geomorphometric analysis. Computers and Geosciences, 95, 75–84.
Lisovets, O., Podorozhniy, S., Tutova, H., Molozhon, K., Kunakh, O., & Zhukov, O. (2025). Hemeroby reveals the dynamics of vegetation cover following the destruction of the Kakhovka Reservoir. PeerJ, 13, e19607.
Midolo, G., Herben, T., Axmanová, I., Marcenò, C., Pätsch, R., Bruelheide, H., Karger, D. N., Aćić, S., Bergamini, A., Bergmeier, E., Biurrun, I., Bonari, G., Čarni, A., Chiarucci, A., De Sanctis, M., Demina, O., Dengler, J., Dziuba, T., Fanelli, G., Chytrý, M. (2023). Disturbance indicator values for European plants. Global Ecology and Biogeography, 32(1), 24–34.
Nykytiuk, Y., Kravchenko, O., & Komorna, О. (2025). How much cropland needs to be converted to forest to offset wind erosion risk? Regulatory Mechanisms in Biosystems, 16(3), e25111.
Nykytiuk, Y., Kravchenko, O., Pitsil, A., Bambura, V., & Seredniak, D. (2025). Global climate change may reduce the anti-erosion regulatory capacity of vegetation cover in Ukraine’s Polissya and Forest-Steppe regions. Regulatory Mechanisms in Biosystems, 33(1), e25004.
Onyshchenko, V. A. (2016). Habitats of Ukraine according to the EUNIS classification. Phytosociocentre, Kyiv.
Pichura, V., & Potravka, L. (2025). Impact of war on natural and climatic transformation of territories in the irrigation zone of Ukraine. Discover Applied Sciences, 7(7), 783.
Pichura, V., Potravka, L., & Boiko, P. (2025). Climatic and hydrological conditions for the formation of vegetation cover in the drained Kakhovka reservoir’s territory. Ecological Engineering and Environmental Technology, 26(4), 357–373.
Pichura, V., Potravka, L., Dudiak, N., & Bahinskyi, O. (2024). Natural and climatic transformation of the Kakhovka Reservoir after the destruction of the dam. Journal of Ecological Engineering, 25(7), 82–104.
Pichura, V., Potravka, L., Stoiko, N., & Dudych, H. (2025). Scenarios for the functioning of the Kakhovka Reservoir territory. Journal of Landscape Ecology, 18(3), 118–154.
Pierce, S., Negreiros, D., Cerabolini, B. E. L., Kattge, J., Díaz, S., Kleyer, M., Shipley, B., Wright, S. J., Soudzilovskaia, N. A., Onipchenko, V. G., van Bodegom, P. M., Frenette‐Dussault, C., Weiher, E., Pinho, B. X., Cornelissen, J. H. C., Grime, J. P., Thompson, K., Hunt, R., Wilson, P. J., … & Tampucci, D. (2017). A global method for calculating plant ecological strategies applied across biomes world‐wide. Functional Ecology, 31(2), 444–457.
R Core Team (2025). R: A language and environment for statistical computing (4.4.2). R Foundation for Statistical Computing, Vienna, Austria.
Raunkiaer, C. (1937). Plant life forms. Clarendon Press, Oxford.
Rendón, P., Watson, M., Czúcz, B., Ruf, K., Kleeschulte, S., & Santos-Martín, F. (2025). Integrating national and international ecosystem typologies for condition assessments: Principles for typology design and policy alignment. One Ecosystem, 10, e163068.
Shumilo, L., Skakun, S., Gore, M. L., Shelestov, A., Kussul, N., Hurtt, G., Karabchuk, D., & Yarotskiy, V. (2023). Conservation policies and management in the Ukrainian Emerald Network have maintained reforestation rate despite the war. Communications Earth and Environment, 4(1), 443.
Shumilova, O., Sukhodolov, A., Osadcha, N., Oreshchenko, A., Constantinescu, G., Afanasyev, S., Koken, M., Osadchyi, V., Rhoads, B., Tockner, K., Monaghan, M. T., Schröder, B., Nabyvanets, J., Wolter, C., Lietytska, O., van de Koppel, J., Magas, N., Jähnig, S. C., Lakisova, V., … & Grossart, H.-P. (2025). Environmental effects of the Kakhovka Dam destruction by warfare in Ukraine. Science, 387(6739), 1181–1186.
Si-Moussi, S., Hennekens, S., Mücher, S., De Keersmaecker, W., Chytrý, M., Agrillo, E., Attorre, F., Biurrun, I., Bonari, G., Čarni, A., Ćušterevska, R., Dziuba, T., Ecker, K., Güler, B., Jandt, U., Jiménez-Alfaro, B., Lenoir, J., Svenning, J.-C., Swacha, G., & Thuiller, W. (2025). EUNIS habitat maps: Enhancing thematic and spatial resolution for Europe through machine learning. Scientific Data, 12, 1976.
Tarasov, V. V. (2012). Flora Dnipropetrovsʹkoyi ta Zaporizʹkoyi oblastey [Flora of Dnipropetrovsk and Zaporizhia regions]. Lira, Dnipropetrovsk (in Ukranian).
ter Braak, C. J. F., & Prentice, I. C. (1988). A theory of gradient analysis. Advances in Ecological Research, 18(C), 271–317.
Ter Braak, Cajo J. F., & Prentice, I. C. (2004). A theory of gradient analysis. Advances in Ecological Research, 34, 235–282.
Tomaselli, V., Mantino, F., Tarantino, C., Albanese, G., & Adamo, M. (2023). Changing landscapes: habitat monitoring and land transformation in a long-time used Mediterranean coastal wetland. Wetlands Ecology and Management, 31(1), 31–58.
Tutova, H., Lisovets, O., Kunakh, O., & Zhukov, O. (2025). Procrustean analysis of the set of spectral indices reveals the transformations in plant community hemeroby and functional structure induced by anthropogenic disasters. Biosystems Diversity, 33(2), e2528.
Tutova, H., Lisovets, O., Kunakh, O., & Zhukov, O. (2026). Ecosystems as organisms in spectral space: Landscape corrosion revealed by unreliable classification zones. Geographies, 6(1), 33.
Tutova, H., Lisovets, О., Kunakh, O., & Zhukov, O. (2025). The future of the Kakhovka Reservoir after ecocide: Afforestation and ecosystem service recovery through emergent willow-popular communities. Studia Biologica, 19(3), 171–194.
Valentini, E., Taramelli, A., Filipponi, F., & Giulio, S. (2015). An effective procedure for EUNIS and Natura 2000 habitat type mapping in estuarine ecosystems integrating ecological knowledge and remote sensing analysis. Ocean and Coastal Management, 108, 52–64.
Xystrakis, F., Chasapis, M., Eleftheriadou, E., Samaras, D., & Theodoropoulos, K. (2022). The optimization of typical species inventory of habitat types of a NATURA 2000 site using a phytosociological approach. Plant Sociology, 59(2), 1–16.
Zhukov, O., Lisovets, O., & Molozhon, K. (2023). Differential ecomorphic analysis of urban park vegetation. IOP Conf. Series: Earth and Environmental Science, 1254, 1–21.
