The role of large mammals in determining forest structure, microclimate, and carbon storage potential

Project background

Large mammal populations are increasing across Europe and their numbers are often controlled to realise forest restoration objectives because high browsing pressure impairs tree seedling recruitment. In some cases, mammals are completely excluded from forests to allow tree regeneration. However, mammalian herbivores are key components of forest ecosystems affecting vegetation diversity and structure, and C and nutrient cycling via direct and indirect pathways 1.

Furthermore, small scale disturbances created by large mammals is now thought to play a key role in creating and maintaining ancient forest structural characteristics and associated biotic communities 2. Despite a growing appreciation of the importance of large mammals in woodland ecosystems, there remain gaps in our knowledge of how mammal activity in forests influence microclimatic conditions, soil biotic communities, vegetation structure and volume of deadwood.

Therefore, habitat management techniques that exclude mammals, or control their numbers, lack a robust evidence base from which to make decisions on how to most effectively realise forest restoration, conservation and carbon storage objectives. Project Aims and Methods

The overarching aim of the studentship is to understand how large mammalian herbivores influence vegetation structure 3,4, microclimate 5,6, soil biotic communities and deadwood volume 7 in forest ecosystems. To achieve this, the candidate will work within a large-scale mammal exclusion experiment with sites in Finland, Germany, Romania, Italy and the UK, and use a combination of terrestrial laser scanning (TLS), an extensive network of soil data loggers and soil eDNA sequencing.

This exciting combination of field work, new technologies and experimental manipulations will allow the candidate to address several key questions relating to the role of mammals within the forests of Europe and provide an evidence base to inform policy as well as forest

management and restoration activities. Example questions include: What impact do large mammals have on soil microclimate and biotic communities, vegetation structural complexity and above-ground carbon stocks in forests? How do 'old growth' characteristics, such as remnant old trees and deadwood, respond to restoration operations, which focus on controlling mammal densities?

How effective are mammal management approaches, interventions, and techniques for enhancing the value of trees and woods (of all ages) for biodiversity? Within the broader remit of the project, prospective candidates will be encouraged to take an active role in shaping the exact direction and nature of the research to best suit their skills and interests.