Nancy Burrell passes her D.Phil viva
Lab member Nancy Burrell passed her D.Phil viva on 13 February 2025 with her thesis titled "What is the carbon storage potential of scrubland created by rewilding?"
Abstract
Climate change represents the most urgent challenge humanity has ever faced, spurring a global race to devise solutions that can prevent irreversible harm to our planet and future generations. Alongside massive and rapid decarbonisation, nature-based solutions are considered to be the most effective way of combating climate change through protection, restoration and sustainable management of natural carbon sinks and reservoirs. Predominant amongst these is reforestation - planting trees to absorb carbon dioxide from the atmosphere. But as governments, NGOs and businesses the world over undertake large-scale tree planting schemes the environmental sector is raising concerns that tree planting does not adequately address the twin crisis of biodiversity loss. Indeed, it may, in some circumstances, actually harm ecosystems and increase carbon emissions. Scientists have, on this account, spelled out the importance of natural regeneration - allowing trees and shrubs to recolonise through natural processes - as a means of establishing tree cover for carbon storage while at the same time helping to restore ecosystems and biodiversity. Rewilding is a particularly effective way of providing conditions for natural regeneration, but its carbon storage potential is poorly understood. There is an assumption that young trees naturally colonising in rewilding projects are adversely affected by the presence of grazing and browsing animals, and smaller woody shrubs characteristic of emergent vegetation are rarely factored into carbon storage calculations. This thesis aims to quantify carbon storage in woody shrubs and emergent trees within a rewilding context and develops a replicable method for calculating above- and below-ground carbon. The goal is to create a landscape-scale method applicable to woody vegetation in temperate rewilding projects, enabling more accurate assessment of its potential as a nature-based climate solution.
Nancy's viva examiners were Professor Lindsay Turnbull (University of Oxford) and Professor Jens-Christian Svenning (Aarhus University). Nancy was supervised by Professor Kathy Willis (University of Oxford) and Professor Marc Macias-Fauria (University of Cambridge).
