Research interests

• Soil ecology and carbon sequestration
• Sustainable farm practices
• Agriculture in a post 2012 Climate Change Agreement
• Greenhouse accounting for agriculture

Thesis

Grazing, roots and soil: interactions and implications for soil function and the sequestration of soil carbon

Thesis description

Grazing lands occupy 70% of agricultural land (3.4 billion hectares) which is mostly unsuitable for more intensive agriculture due to climatic and edaphic conditions.  About 73% is degraded resulting in depleted soil C levels and reduced productivity, which is likely to worsen with climate change.  This has serious implications for provision of ecosystem services from food production to water and climate regulation.

Although grazing is a recognised cause of land degradation, co-evolution of grasslands and grazing animals over millennia, indicates that degradation is caused by inappropriate grazing management and not grazing of itself.  Indeed, anecdotal evidence of Holistic Planned Grazing (HPG) that mimics large herd migrations, suggests that grazing animals can be used as a tool to regenerate degraded land, improve soil function and build soil carbon.  However, there is little research on HPG and results of grazing studies generally vary and are often contradictory.

My research seeks to develop an ecological understanding of whether and how this bio-mimicry is intrinsically different to conventional grazing methods in relation to soil function and the soil’s ability to sequester carbon is needed.  It utilises a range of methods covering pasture perenniality, root biomass and soil chemical, and biological properties.  Developing this ecological understanding will be a key contribution, to the understanding of interactions of grazing and soil and the implications for soil function and the sequestration of soil carbon.  This basic understanding would inform decisions of land managers and policy makers, including for grazing management and accounting for soil carbon.