International workshop on

Koli (c) Metla/Erkki Oksanen

Development of Models and Forest Soil Surveys for Monitoring of Soil Carbon

April 5-8, 2006 at Koli, Finland

Comparing and predicting soil carbon quantities under different land use systems on the Red Ferrosol soils of Southeast Queensland

Tek Narayan Maraseni1*, Nicole J. Mathers2,3, Ben Harms2,3, Geoff Cockfield1 and Armando Apan4

1 Department of Economics & Resources Management, University of Southern Queensland (USQ),
Toowoomba, Qld, 4350, Australia.
2 CRC for Greenhouse Accounting, GPO Box 475, Canberra, ACT 2601, Australia.
3 Department of Natural Resources and Mines, 80 Meiers Rd, Indooroopilly, Qld 4068, Australia.
4 Australian Centre for Sustainable Catchment & Faculty of Engineering and Surveying, USQ,
Toowoomba, Qld 4350, Australia.
* Corresponding Author: e-mail:, Phone +61-7-46311274

Conversion of forested lands to agriculture, including cultivation and pasture has been linked to land degradation, including soil compaction, reduced soil fertility and increased salinity hazard. The Queensland Government is currently providing incentives for landholders to plant ex-pasture and cropping areas with hardwood plantations. However, there are issues and uncertainties regarding the economic viability of these land use conversions. Carbon credits resulting from additional carbon (C) sequestration achieved in the plantations are now recognised under the Kyoto Protocol, but the nature of the carbon trading scheme that will apply is still unclear, as Australia has not ratified the Protocol. This study compared the total soil C under native scrub (subtropical dry vine forest), grazed pasture, cultivation and spotted gum (Corymbia citriodora) forest on the Red Ferrosol soils of the Kingaroy region in southeast Queensland (SEQ). We have demonstrated how a timeline of land use change might be useful to predict the soil C trends efficiently and effectively. Cumulative soil C (including surface litter and particulate organic matter) to 1.2 t m -2 dry soil ranged from 72 t ha -1 at the cultivated site to 281 t ha -1 under the mature spotted gum forest. The predicted annual rate of soil C loss under cultivation was 2.1%, which was similar to the ROTHC predicted value. The annual rates of soil C gain under pasture and spotted gum plantation were predicted to be 1.1 and 1.4%, respectively.Therefore there is considerable potential for spotted gum plantations to sequester soil C when planted on ex-agricultural land in SEQ.

Key words: Red Ferrosol, land use change, dry land farming, inland Queensland, carbon sequestration, carbon credits.

   Päivitetty:   02.03.2006 / EKel Metla : Events   Palaute Metlan etusivulle
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