Impacts of fire on soil organic carbon stocks in a grazed semi-arid tropical Australian savanna: accounting for landscape variability

2014 ◽  
Vol 36 (4) ◽  
pp. 359 ◽  
Author(s):  
D. E. Allen ◽  
P. M. Bloesch ◽  
R. A. Cowley ◽  
T. G. Orton ◽  
J. E. Payne ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Spatial Variability ◽  
Management Practices ◽  
Soil Depth ◽  
Carbon Stocks ◽  
Soil Organic Carbon Stocks ◽  
Semi Arid ◽  
Soc Stocks

Fire and grazing are commonplace in Australian tropical savannas and the effects of these management practices on soil organic carbon stocks (SOC) is not well understood. A long-term (20 years) experiment studying the effects of fire on a grazed semi-arid tropical savanna was used to increase this understanding. Treatments, including frequency of fire (every 2, 4 and 6 years), season of fire [early (June) vs late (October) dry season] and unburnt control plots, were imposed on Vertosol grassland and Calcarosol woodland sites, which were grazed. Additionally long-term enclosures [unburnt (except the Calcarosol in 2001) and ungrazed since 1973] on each soil type adjacent to each site were sampled, although not included in statistical analyses. SOC stocks were measured to a soil depth of 0.3 m using a wet oxidation method (to avoid interference by carbonates) and compared on an equivalent soil mass basis. Significant treatment differences in SOC stocks were tested for, while accounting for spatial background variation within each site. SOC stocks (0–0.3 m soil depth) ranged between 10.1 and 28.9 t ha–1 (Vertosol site) and 20.7 and 54.9 t ha–1 (Calcarosol site). There were no consistent effects of frequency or season of fire on SOC stocks, possibly reflecting the limited statistical power of the study and inherent spatial variability observed. Differences in the response to frequency and season of fire observed between these soils may have been due to differences in clay type, plant species composition and/or preferential grazing activity associated with fire management. There may also have been differences in C input between treatments and sites due to differences in the herbage mass and post-fire grazing activity on both sites and changed pasture composition, higher herbage fuel load, and a reduction in woody cover on the Vertosol site. This study demonstrated the importance of accounting for background spatial variability and treatment replication (in the absence of baseline values) when assessing SOC stocks in relation to management practices. Given the absence of baseline SOC values and the potentially long period required to obtain changes in SOC in rangelands, modelling of turnover of SOC in relation to background spatial variability would enable management scenarios to be considered in relation to landscape variation that may be unrelated to management. These considerations are important for reducing uncertainty in C-flux accounting and to provide accurate and cost-effective methods for land managers considering participation in the C economy.

Land use and climate change impacts on soil organic carbon stocks in semi-arid Spain

2012 ◽  
Vol 13 (2) ◽  
pp. 265-277 ◽  
Author(s):  
Juan Albaladejo ◽  
Roque Ortiz ◽  
Noelia Garcia-Franco ◽  
Antonio Ruiz Navarro ◽  
Maria Almagro ◽  
...  
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Climate Change Impacts ◽  
Carbon Stocks ◽  
Soil Organic Carbon Stocks ◽  
Semi Arid

scholarly journals Spatial Distribution of Soil Organic Matter and Soil Organic Carbon Stocks in Semi-Arid Area of Northeastern Syria

2019 ◽  
Vol 10 (12) ◽  
pp. 415-432
Author(s):  
Hussam Hag Husein ◽  
Mohammad Mousa ◽  
Wahib Sahwan ◽  
Rupert Bäumler ◽  
Bernhard Lucke
Keyword(s):  
Organic Matter ◽  
Spatial Distribution ◽  
Soil Organic Matter ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Carbon Stocks ◽  
Arid Area ◽  
Soil Organic Carbon Stocks ◽  
Semi Arid
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