Carbon Sequestration from Revegetation in Agricultural Landscapes — ASN Events

Carbon Sequestration from Revegetation in Agricultural Landscapes (7793)

Trevor Hobbs 1 2 , Craig Neumann 1 2 , Merv Tucker 1 2
  1. SA Department of Environment, Water & Natural Resources, Adelaide, SA, Australia
  2. Future Farm Industries Cooperative Research Centre, Adelaide, SA, Australia

South Australia has the potential to sequester significant amount of carbon from revegetation in agricultural landscapes. Dedicated woody carbon crops, sustainable agroforestry and environmental plantings can be used to store atmospheric carbon, deliver economic and environmental benefits, enhance biodiversity and provide greater resilience to climate change for our rural communities.

The influence of climate change on traditional farming businesses, expected expansion of carbon markets, and trends towards more sustainable land use options suggest that future agricultural landscapes will contain greater diversity of land uses, including carbon crops, woodlots and environmental revegetation. To evaluate the economic and potential expansion of these crops land managers and governments require clearer information on the carbon sequestration potential of revegetation. The production rates of local native species found in environmental plantings are poorly represented in most current models used to estimate carbon sequestration from revegetation.

This study provides estimates of carbon sequestration rates from a variety of revegetation activities in the low to medium rainfall (250-650mm/year) dryland agriculture zones of South Australia. Total above-ground plant biomass and carbon content were assessed for 264 revegetation sites in the agricultural landscapes.  The average carbon sequestration rate was 11.4 CO2-e t/ha/year for woodlots (at 441mm/year) and 7.6 CO2-e t/ha/year in environmental plantings (at 418mm/year). Productivity of agricultural landscapes can be highly variable and is strongly influenced by species choices, planting designs, soils, land management practices and climatic conditions.

Analyses of the relationships between carbon sequestration rates and planting designs, climates and soils has allowed the development of robust models to predict average carbon sequestration rates in agricultural landscapes. These models have been embedded within a user-friendly spreadsheet tool that allows individuals to estimate carbon sequestration rates and stocks over time using regional or localised site data, and explore the influence of climate change on sequestration rates.

Carbon sequestration from revegetation models have been applied to spatial climate/soils data across the agricultural regions of the state.  This work has produced maps of typical sequestration rates for the state and each Natural Resource Management (NRM) region. Summaries of these predictions for cleared agricultural lands have been tabulated for each NRM region, rainfall zone, cropping district, state planning division, local government region and IBRA subregion.