Forest monitoring and upscaling
“From feeling the pulse of the trees to sustainable landscape management”
Deepening our physiological understanding of the dynamics of single trees is crucial for making informed decisions in forest and landscape management, given the challenges ahead. However, trees do not grow in isolation, but they form stands where they interact in complex ways. As a result, forest stand dynamics show many emergent traits that cannot easily predicted from single tree dynamics.
For sustainable forest management, the system level of forest stands is extremely important for several reasons. Most prominently, forest management is always bound to an area that must be utilized as prudently as possible given a system of management goals, typically providing a set of desired ecosystem services. Therefore, the dynamics of an isolated tree alone are much less important for management than the dynamics of many trees that together form a stand. However, most of our understanding of tree responses to climate change is measured at the tree level. In our group, we focus on the scaling between the tree and the stand level. At the interface between these two levels, we see a wide gap between empirically acquired knowledge of stand-level dynamics and their causal explanation with physiological mechanisms. Decisions about which silvicultural concepts to use or modify under climate change would significantly profit from such advances.
We focus on classic forest growth and yield variables like wood volume, volume increment, stand densities, tree size distributions, and many more on the tree, stand, and higher levels. We rely on long-term experimental and monitoring plot networks and grid-based repeated forest inventories from enterprise up to the national level. These data allow us to uncover principles of forest stand dynamics that find their way into silvicultural concepts. On the other hand, relating these principles to physiological processes has been hampered in the past due to the costly instrumentation that ruled out applications to larger samples of interacting trees. Here, we see great potential in deploying novel, affordable sensor technologies, such as dendrometers, which can provide near real-time information on tree growth and stress that can be directly upscaled without requiring assumptions in between. Our overarching goal is to advance to the next generation of forest monitoring.
For more information on this research, please contact Peter Biber. An overview of related projects can be found here.
Example of current silvicultural practice and natural disturbances, gaps become increasingly prominent elements of forest stand structure. In this study, we could show that gap edge trees show growth reactions that are not automatically covered with single-tree-based stand simulation models. This example is adjusted from Biber & Pretzsch (2022).