Smith, James

Curriculum Vitae

PhD Project

Scaling Biodiversity to Ecosystem Services: Spatial Genetic Structure and Carbon Sequestration Potential in Tropical Forest Trees

Deforestation accounts for around 17-25% of global carbon emissions. International climate change negotiations aim to implement policies to prevent deforestation and forest degradation, notably through REDD (Reducing Emissions from Deforestation and forest Degradation) and its successor REDD+. Whilst gazetting forests will protect carbon stocks in the short term, the long-term viability of protected forests requires the effective functioning of ecological processes underlying plant reproduction, namely pollination and seed dispersal. These processes directly contribute to population viability through propagule production, but also shape the spatial genetic structure (SGS) of populations, inbreeding, reducing the genetic quality of seed, and hence the capacity of populations to adapt to changing environmental conditions.

One family of trees in which both carbon storage objectives and plant reproductive processes have particular relevance is the Dipterocarpaceace. Dipterocarps dominate Southeast Asian rain forests, comprising around 80% of canopy trees and 40% of basal area in Bornean forests. Preliminary studies suggest that wood density (and carbon storage potential) is inversely correlated with potential gene flow mediated by both seed dispersal and pollination. If robust, these relationships suggest that the susceptibility of tree species to constrained gene flow, caused by forest degradation and/or fragmentation acting on pollination or seed dispersal, might be predictable from wood density alone. A particular vulnerability of high wood density species, which contribute disproportionately to community biomass, as well as community-wide changes in the genetic diversity of species, would raise concerns about the viability of populations and the carbon sequestration potential of forests in the short and long term.

This project therefore aims to quantify putative relationships between wood density, reproductive traits, gene dispersal and spatial genetic structure of dipterocarp trees in Borneo, with a view to informing policy and management practice on forest restoration and carbon sequestration. These relationships will be tested using a mix of molecular and ecological approaches. Fieldwork will be conducted in Sabah, Malaysian Borneo.