Floodplain forests are the most rapidly disappearing ecosystem in the world, especially in temperate regions of Europe where anthropogenic influence has been pronounced throughout history. Research on primeval forests is crucial to further our understanding of their natural dynamics and interaction with climate but is limited by the lack of such preserved forests. The aim of this study was to investigate how a primeval floodplain forest in Southeastern Europe has responded to climate variability during the last 250 years through comparison of tree growth and climate, canopy disturbance and recruitment dynamic of two dominant tree species with different tolerances to flooding/drought. Our analysis revealed induced stress caused by several consecutive severe drought events in the 1940s, which led to a significant increase in sensitivity to increasing temperatures and decreasing river water levels. This trend is particularly pronounced in pedunculate oak. Age structure analysis revealed one larger episode of oak regeneration culminating after periods of intense growth release. Such period co-occurs with summer drought, which is part of a complex system of natural disturbances and a significant natural driver of the cyclical regeneration of primeval oak ecosystems.

Current flood risk management is based on statistical models and assessments of the risk of occurrence over a given time period, although with very short measurement periods, usually following catastrophic events. Ongoing monitoring of basic hydrological (river-water level and streamflow) and climate data are the basis for sustainable water management and long-term flood control planning. The lack of data has proven to be particularly negative during this period of global climate change, when non-seasonal flooding (during summer) is becoming increasingly frequent, and the resulting damage greater. The aim of this study was to analyse the possible use of tree ring width chronologies of trees growing in floodplain areas to reconstruct hydrodynamic variables (river-water level and streamflow). The study analysed the influence of climatic and hydrological variables on the growth of narrow-leaved ash (Fraxinus angustifolia Vahl) in the Sava River basin. The results indicate the significant potential of narrow-leaved ash tree-ring width chronologies to reconstruct the summer streamflows of the Sava River (R2 = 0.45). These results can serve to develop long-term data series on the summer streamflows of the river, thereby enabling better insight into its spatial and temporal dynamics with the goal of more successful, sustainable management of floodplain areas.

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Zabrinutost oko mogućih posljedica klimatskih promjena i njihovog utjecaja na Mediteransko područje ukazuje na potrebu boljeg razumijevanja varijabilnosti klime dugo u povijest, a posebice izvan razdoblja obuhvaćenih instrumentalnim mjerenjima. Kako bismo poboljšali prostornu i vremensku pokrivenost hrvatskog Sredozemlja klimatskim podacima te bolje razumjeli utjecaj klimatskih promjena na rasta stabala, provedena su prva dendrokronološka istraživanja na području Sjevernog Velebita. Rezultati istraživanja 274 godine stare kronologije crnoga bora ukazuju da je glavni limitirajući čimbenik rasta stabala crnoga bora nedostatka vlage u ljetnom razdoblju godine. Korelacije kronologije rasta stabala i količine ljetnih oborina od 1954. do 2015. godine su značajne i pozitivne (R=0.60, p=0.0099) te vremenski stabilne. Time se stvorila mogućnost rekonstrukcije klime relativno daleko u prošlost za područje sjeverozapadnih Dinarida.