1. The Carbon Farming Initiative and Agricultural Emissions This presentation was prepared by the University of Melbourne for the Regional Landcare Facilitator training funded through the Australian Government’s Carbon Farming Initiative Communications Program

2. This presentation provides a basic understanding of the soil, plant and animal carbon and nitrogen cycles PART 1: INTRODUCTION TO THE SCIENCE OF AGRICULTURAL EMISSIONS AND SINKS

3. The Carbon cycle http://www.davidsuzuki.org/files/CCcarboncycle.GIF C-stocks in Pg (Gt), C-fluxes in Pg yr -1 ; Pg = 10 15 g = 1 Gt (gigatonne) More carbon emissions than carbon uptake  fossil fuel emissions Increase carbon sinks – increase terrestrial plant or soil sinks Large carbon pools, relatively small fluxes between pools

4. Global forest distribution www.fao.org/forestry

5. Sources of global CO 2 emissions 12% of total anthropogenic emissions Le Quéré et al. 2009, Nature-Geoscience; Data: CDIAC, FAO, Woods Hole Research Center 2009 Slide courtesy of J. Canadell, Global Carbon Project Fossil fuel Land use change 10 8 6 4 2 1960 20101970 1990 2000 1980 CO 2 emissions (PgC y -1 )

6. Carbon stocks and sequestration Carbon stock/pools Carbon sequestration How much C at one point in time Change of C stock over time Aboveground biomass Leaves, stem, branches Below ground biomass Coarse roots, fine roots, microbes Soil carbon Stable and labile fractions Litter & coarse woody debris

7. NPP

8. Net primary productivity Tropical forest are the most productive Forests produce most of the terrestrial carbon Saugier (2001) IN: Terrestrial Global Productivity 0.5 2.6 8.1 21.9 14.9 7.0 3.5 4.1 NPP Pg C yr -1 Crops produce mainly aboveground NPP  consequences for soil C belowground aboveground

9. The Carbon cycle Human activity greatly influences the global C cycle The sink capacity of natural CO 2 sinks is decreasing, leading to increased atmospheric CO 2 Forest ecosystems are the greatest carbon sink in the terrestrial biosphere Globally, soils store more C than biomass The capacity of an ecosystem to store C is determined by the balance of C uptake (photosynthesis) and C loss (respiration)