Effective strategies to deal with climate change Climate change is set to have a significant impact on Europe’s forests, with changing levels of water availability likely to affect their ability to provide key ecosystem services. Understanding how plants respond to climate variability is central to forecasting how they will respond to future change, as Dr Elisabeth Robert and Dr Jordi Martínez-Vilalta explain Our forests play a number of ecologically important roles, including both producing oxygen and removing CO2 from the atmosphere. However, climate change and other pressures are likely to affect forests’ ability to perform these roles in future, a point which underlines the importance of the Phloemap project’s work. “We aim to understand how plants adjust to changes in climate, and with that build a better understanding of how they might respond to future climate change,” says Dr Elisabeth Robert. A key priority in research is to investigate the traits that determine how tree species use water. “Our main aim was really to understand better how plants adjust to different levels of water availability. So we’re focusing on the traits that we suspect are related to this,” outlines Jordi Martínez-Vilalta.
PHLOEMAP Hydraulic functional traits as determinants of forest function and drought responses. Putting xylem and phloem attributes into the functional trait map EU H2020 Marie Curie IF grant (659191) Centre for Ecological Research and Forestry Applications Universitat Autònoma de Barcelona - Campus de Bellaterra - Edifici C 08193 Cerdanyola del Vallès, Spain T: +34 935 81 38 11 E: Jordi.Martinez.Vilalta@uab.cat PHLOEMAP project: http://www.creaf.cat/ hydraulic-functional-traits-determinants-forestfunction-and-drought-responses-putting-xylemand-phloem-attributes-functional-trait-map FUN2FUN project: http://www.creaf.cat/ functional-traits-approach-forest-function-anddynamics-implications-provision-ecosystemservices-under-climate-change
Elisabeth M.R. Robert (right) obtained a PhD in Sciences from the Vrije Universiteit Brussel (Belgium) in 2012. In 2016, she joined CREAF to work on the PHLOEMAP project, thanks to a EU Marie SkłodowskaCurie individual fellowship. Jordi Martínez-Vilalta (left) obtained a PhD in Environmental Sciences at the Universitat Autònoma de Barcelona (UAB) in 2001. He is now Senior Lecturer at UAB and researcher at CREAF, has been Honorary Fellow at the University of Edimburg (UK) and currently holds an ICREA Academia award.
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Tree species This research centres around analysing specific traits in six different tree species commonly found across Catalonia, and indeed much of the Western Mediterranean. The traits selected represented the anatomy of the tree, part of the structural component of the wood. “One of the traits we measured was, for example, the size of the cells which transport water in trees. Are there differences among the different tree populations and different species in relation to water transport capacity?” asks Dr Robert. The project researchers are studying these species across 90 study sites; despite its relatively small size, Catalonia has a high degree of climate variability, and the study sites have very different levels of water availability. “We sampled each of the species at 15 of these sites. We took a comprehensive measurements of environmental variables – so for example measurements of climate variables and certain soil characteristics,” continues Dr Robert.
further information. “We’ve got information on the dynamics of how forests change over time. We can then relate this with the data that we are gathering now to determine which traits underlie the response of these forests to climate over recent decades,” he explains. This could help researchers build a deeper understanding of how forests might respond to future climate change. “We can use this information to improve our ability to forecast how forests might respond in the future,” says Dr Martínez-Vilalta.
Climate change The backdrop to this research is growing concern about the impact of climate change. Catalonia as a region is experiencing higher temperatures, which leads to higher demand for water in forests. “The fact that temperatures are rising means that there will be more atmospheric water demand for forests. This essentially means that water will evaporate faster and that forests will need more water,” explains Dr Martínez-Vilalta.
Our main aim was really to understand better how plants adjust to different levels of water availability. So we’re focusing on the traits that we suspect are related to this The project’s work is complemented by the work of the Fun2fun initiative, in which scientists have taken additional measurements of the same trees, aiming to help better their knowledge of forest ecosystems. The combined work of these two projects enables researchers to build a deeper picture of how forests adapt to climate variability. “We can draw bridges between the cellular level – where the actual water transport occurs – and the forest level, at which decision making takes place,” explains Dr Robert. “The special aspect of these two projects is that these different scales are brought together in a design that allows us to understand the structural (anatomy) and functional (physiology) variability which exists in a forest, and from there upscale and draw conclusions at forest scale.” The Spanish government has also conducted several large-scale national forest inventories over the last 25 years, so Dr Martínez-Vilalta and his colleagues have access to a wealth of
The project will play an important role in understanding and forecasting how forest ecosystems will change in the future, and Dr Martínez-Vilalta is working with regionalscale modelling of vegetation dynamics to gather information. “A very important factor that we need to consider in our models is wild fires. The higher the temperature the higher the likelihood of wildfires,” he says. Three dimensional visualisation of a small proportion of the water transporting tube system within the stems of trees. Different water conducting tubes are visualised in different colors.
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