Impact of hydraulic Redistribution by Trees on Temperate Floodplain Forests - ImpaRT
This project aims at assessing the effects of hydraulic redistribution (HR) of adult floodplain forest trees on surrounding juvenile trees during summer drought in the lower Middle Elbe area. At nighttime, when stomata are closed and transpiration is suppressed, roots can transfer water between soil layers of different water potential. Thereby, water is lifted from moist to dry soil where it can be accessed by shallow rooted neighbouring plants. This process, termed HR, has been mainly shown for plants of arid regions, but has never been studied in temperate floodplain ecosystems. There, HR may be a highly important process facilitating the prolonged survival of juvenile trees that surround adult trees during increasingly severe summer droughts caused by climate change. Drought stress affects the C-isotopic signature of the impacted species and is distinctive from the isotopic ratio of non-stressed plants. By analysing the isotopic composition of floodplain trees, an isotopic map (isoscape) will be established that shows to what range adjacent plants may benefit from HR by a nearby tree. Also xylem sap flow will be measured in the main floodplain tree species Quercus robur, Fraxinus excelsior and Ulmus laevis using heat-field-deformation sensors on stems and roots. Assessing the importance of HR for floodplain forests is a crucial contribution to nature conservation and the restoration of these threatened ecosystems. As floodplain forests are carbon sinks, their protection contributes to the targeted reduction of EU greenhouse gases. Dr. Eller, the researcher in this project, will gain significant insights into floodplain ecosystems and species interactions under drought stress. She will have the possibility to establish an international network with the host researcher´s collaborators in the Netherlands, UK and USA, and supervise PhD and MSc students. This will enable her to apply for a permanent research position in wetland ecology subsequent to the fellowship.
- Dauer: 03/2014 - 10/2015
- Projektleitung: Dr. Franziska Eller
- Drittmittelgeber: Carlsberg Foundation