The role of tree diversity for ecosystem functioning, resilience and delivery of ecosystem services

Prof. Michael Scherer-Lorenzen

Date: July 30, 2020
Time: 3 pm (s.t.)
Place: zoom. Please register by sending an email to grk2300@uni-goettingen.de.

A number of global change drivers, such as land use change and management, climate change, or air-borne eutrophication, have considerable impacts on the biological diversity of forest ecosystems. Understanding and forecasting the consequences of these changes in biodiversity on ecological processes, functions and the delivery of ecosystem services is certainly one of the major challenges for ecological research.

Current research on the functional significance of forest biodiversity, e.g. from large-scale projects such as FunDivEUROPE and TreeDivNet, suggests a positive relationship between tree diversity and functions related to productivity, associated biodiversity, and soil parameters, as well as related to ecosystem stability. However, no and even negative effects were also documented for other ecosystem processes, and many studies find stronger effects of species identity than diversity. In addition, disentangling the diversity signal from confounding environmental heterogeneity remains difficult. Comparisons of tree species performance in pure and mixed plantations imply that changes in light acquisition and plant nutrition may be important underlying mechanisms for the observed diversity effects.

The question then arises whether we can design mixed species forest stands that capitalize on the different diversity effects to enhance and stabilize the delivery of multiple ecosystem services. So, can we use the diversity of trees as a tool to manage future forests? This implies consideration of knowledge at very different levels, ranging from species functional traits, interspecific mixing effects, but also trade-offs between different ecosystem services or stand versus landscape perspectives.