How can we measure forest performance?
Forests are important natural habitats with relevance for atmospheric carbon dioxide levels and for wood-production. How can measure forest well-being, the impact of climate change or of other human-caused disturbances? To answer this question, scientists from various European countries analysed data from 209 stands from six European forests. Their study demonstrated that leaf fluorescence provides useful information on tree performance and productivity.
Leaf fluorescence is mainly caused by chlorophyll, the primary plant pigment involved in photosynthesis. This feature of plant leaves is connected to plant productivity and can be measured relatively quickly and easily. Research in recent years has demonstrated that leaf fluorescence is reflecting the leaf’s mode of action and is influenced by various environmental factors. Measurements in 209 different stands from 6 forests in various regions of Europe now showed that leaf fluorescence indeed allow differetiating leaf functional groups (for example broad-leaved trees versus conifers) and the impact of various environmental factors (like drought or temperature). Authors demonstrated in addition, that fluorescence data allow assertions about specific tree features like leaf nitrogen content or wood density. While the data analyzed were obtained from hand-held ground-based devices authors cautioned that remotely assessed data are not yet ripe for a similar analysis.