Adapt forest management to climate change: modulating stand composition, stand density and browsing pressure.

The OPTMix (Oak Pine Tree Mixture) field experiment is celebrating its 10th anniversary with an international symposium inviting us to question management options in the face of climate change. OPTMix was set up in the Orléans National Forest in France. The experimental site aims to study the effect of stand composition, stand density and browsing pressure on forest functioning under climate change in lowland oak-pine temperate forests

Adapting forest management to climate change, particularly in response to drought, extreme temperatures and biotic hazards, is a major concern. Climate change is forcing forest owners and managers to question their silvicultural practices. Some management practices are expected to be part of the solution, such as increasing tree species diversity or lowering stand density. For instance, mixing tree species is assumed to provide higher productivity, higher temporal stability, lower risk of biotic and abiotic disturbances, higher biodiversity levels, and other services. Reducing tree density is supposed to reduce competition between trees and improve resource availability, especially water. However, is it relevant, and to what extent? Can it be used everywhere?

The symposium aims to gather researchers and forest engineers and discuss the effects of silvicultural choices on forest functioning in the context of climate change. It focuses on the effect of the three factors studied in OPTMix: (1) stand mixture, (2) stand density, and (3) the presence of wild ungulates. We encourage contributions that address the effect of one or more of these factors on:

• Theme 1 - Biodiversity: concerns research mobilizing community ecology approaches on one or several taxonomic groups together. Studies at different spatiotemporal scales or cascading effects are appreciated.
• Theme 2 - (Eco)physiological functioning of trees and the role of environmental conditions (e.g. microclimate, resource availability): includes work on tree growth, dieback, resistance, and resilience to climatic hazards, pests, and diseases, as well as understanding biogeochemical cycles and the distribution of forest resources.
• Theme 3 - Regeneration and the effects of large wildlife: covers work on the role of wild ungulates (deer, roe deer, wild boar) on the establishment and maintenance of woody regeneration, as well as on soil properties, carbon, and nutrient cycles.

This international conference is open to the academic world, socio-economic partners, and research and development agents concerned with adaptation to climate change in European forests. This congress provides an opportunity to discuss the latest scientific knowledge in various fields related to both forest functioning and management in the context of global change. Contributions can be an oral presentation (30-minute intervention or 10-minute intervention) or a participation in a poster session.