Drought Superimposes the Positive Effect of Silver Fir on Water Relations of European Beech in Mature Forest Stands

摘要: Research Highlights: Investigations of evapotranspiration in a mature mixed beech-fir forest stand do not indicate higher resilience towards intensified drying-wetting cycles as compared with pure beech stands. Background and Objectives: Forest management seeks to implement adaptive measures, for example, the introduction more drought resistant species into prevailing monospecific stands minimize mortality monetary losses. In Central Europe this includes native silver fir (Abies alba) (Fagus sylvatica) order determine, if would improve against drier conditions, study investigates water relations under natural well reduced availability. Materials Methods: Sap flow rates densities were measured two consecutive years using heat ratio method scaled inventory data modeling. Results: Transpiration estimated from sap significantly trees which was attributed anisohydric water-use strategy trees. We estimate that slightly due interception losses during times above average supply. When precipitation restricted, able support its transpiration demands, therefore there mixed, stand, whereas largely unaffected, likely isohydric behavior toward use access moister soil layers. Thus, we found be smaller no accountable severely stand. Conclusions: conclude might result increased efficiency but rather caused by restricted hydraulic conductivity root system beech, making at site less resilient drought.