Impact of climate changes on aquatic vegetation of hydromeliorative facilities

Abstract

© 2015, Pleiades Publishing, Ltd. Distributions of 20 aquatic associations in the Danube-Tisza-Danube hydrosystem were mapped using published data and personal field observations resulting in 562 georeferenced collection sites. The Maxent modeling software was used to estimate the current potential and future distribution of the associations by the year 2050 (2xCO2 climate conditions, CCM3 model). Based on the Principal Component Analysis (PCA), climate data at the collection sites described climatic preferences of different aquatic associations. The central-eastern part of the investigated area showed the most favorable climatic conditions for aquatic vegetation growth and thus the highest potential for future biodiversity. The stands of Lemnetum trisulcae, Ceratophyllo-Azolletum filiculoides, Najadetum marinae, Salvinio natantis-Spirodeletum polyrhizae, Elodeetum canadensis and Potametum denso-nodosi associations displayed a marked invasive potential in the forecasted distribution scenarios. The results revealed that the stands of Nymphaeetum albae and Nymphaeo albae-Nupharetum luteae subass. nupharetosum associations are likely to be significantly less abundant in the future. As the key climatic factors used in the analysis were annual mean temperature, as well as mean temperature of the wettest and warmest quartile, the findings suggest that, if adequate protective measures shall not be taken, these provenances could become degraded in the next decade and some could even become extinct at the locations where they presently occur naturally.