Research Team

Case Study Area

Model Evaluation Work

Related Publications

Research Team

The Brazilian case study is being run by Centro de Energia Nuclear na Agricultura (CENA) which is part of The University of Sao Paulo, in association with the L'institute de recherche pour le development (IRD), France. The Principal investigator for the case study is Dr Carlos Clemente Cerri with Dr Carlos Eduardo Cerri employed as the case study Postdoctoral Research Fellow.  They are working in association with Dr Martial Bernoux and Dr Christian Feller from IRD.

Case Study Area

Due to the size of Brazil, the Brazilian Case Study is concentrating on the Brazilian Amazon only. The Amazon rainforest covers an area of over 7 million km², larger than the area of Western Europe. The majority of Amazon Rainforest lies inside Brazil with the Brazilian Amazon having an area of over 5 million km². 

Estimated deforestation rates range from 1.1 million to 2.9 million ha yr^-1 with the total area cleared reaching approximately 50 million ha in the mid 1990s, (approximately 10% of the total Basin area). Cattle pasture represents the largest single use (about 70%) of cleared forest land in most of the Brazilian Amazon.

Terrain The Brazilian Amazon is located in the low lying Amazon Basin. SThe Amazon river system is the single, largest source of fresh-water on Earth, carrying an astounding 16 percent of all the river water in the world over its 6,500 miles. A fifth of all river water discharged into the world's oceans is conveyed through the Amazon, 10 times that of the Mississippi River. The flow regime of The Amazon river is impacted relatively little by humans and is subject to interannual variability in tropical precipitation that is ultimately translated into large variations in downstream hydrographs. The recycling of local evaporation and precipitation by the forest accounts for a sizable portion of the regional water budget.

Climate The Amazon region is of particular interest because it has been shown to have a significant impact on extra-tropical circulation, being the Earth’s largest and most intense land-based convective centre. Rainfall levels in the area range from 1500 to 4000 mm yr^-1.

Soils The Amazon region is dominated by old, highly weathered, leached soils, a result of large areas of tectonically and geomorphologically stable land surfaces. The main soils developed under these conditions can be grouped under modal Kaolisols, which include the ferralitic soils (FAO-UNESCO) or Oxisols and Ultisols (Soil Survey Staff). Two soils, Latossolos and Podzolicos (Brazilian Classification), make up 73% of the total area of the Brazilian Amazon. Just three dystrofic soil types, Podzolico Vermelho Amarelo (Acrisol), Latossolo Amarelo (Xanthic Ferralsol), and Latossolo Vermelho Amarelo (Orthic Ferralsol) cover approximately 60% of the total area.  

Model Evaluation Work

Long-term experimental datasets that have measured soil carbon are lacking in the Brazilian Amazon. The Brazilian Case Study Group are therefore using land use chronosequences to evaluate the two SOM models being used in the project. These chronosequences consist of areas of forest surrounded by areas of pasture, which were deforested at different points in the past but are otherwise similar in terms of soil type and climate. Eleven such datasets have been identified throughout the Brazilian Amazon which are reasonably representative of the conditions found in the area.

Cerri, C.E.P., Easter, M., Paustian, K., Killian, K., Coleman, K., Bernoux, M., Falloon, P., Powlson, D.S., Batjes, N.H., Milne, E., Cerri, C.C., 2007 ‘Simulating SOC changes in 11 land use change chronosequences from the Brazilian Amazon with RothC and Century models’ In: Milne, E., Powlson, D.S., Cerri, C.E.P. (Eds.), Soil carbon stocks at regional scales. Agric. Ecosyst. Environ., (available on-line).

Cerri, C.E.P., Easter, M., Paustian, K., Killian, K., Coleman, K., Bernoux, M., Falloon, P., Powlson, D.S., Batjes, N.H., Milne, E., Cerri, C.C., 2007. ‘Predicted soil organic carbon stocks and changes in the Brazilian Amazon between 2000 and 2030’ In: Milne, E., Powlson, D.S., Cerri, C.E.P. (Eds.), Soil carbon stocks at regional scales. Agric. Ecosyst. Environ., (available on-line).

Bernoux, M., D. Arrouays, C.C. Cerri, and H. Bourennane. 1998a. Modeling vertical distribution of carbon in oxisols of the western Brazilian Amazon (Rondonia). Soil Science 163:941-951.

Bernoux, M., C.C. Cerri, C. Neill, and J.F.L. de Moraes. 1998b. The use of stable carbon isotopes for estimating soil organic matter turnover rates. Geoderma 82:43-58.

Bernoux, M., M.D.S. Carvalho, B. Volkoff, and C.C. Cerri. 2001. CO2 emission from mineral soils following land-cover change in Brazil. Global Change Biology 7:779-787.

Bernoux, M., M.D.S. Carvalho, B. Volkoff, and C.C. Cerri. 2002. Brazil's soil carbon stocks. Soil Science Society of America Journal 66:888-896.

Bonde, T.A., B.T. Christensen, and C.C. Cerri. 1992. Dynamics of Soil Organic-Matter as Reflected by Natural C-13 Abundance in Particle-Size Fractions of Forested and Cultivated Oxisols. Soil Biology & Biochemistry 24:275-277.

Cerri, C.C., and B. Volkoff. 1987. Carbon Content in a Yellow Latosol of Central Amazon Rain- Forest. Acta Oecologica-Oecologia Generalis 8:29-42.

Cerri, C.C., B. Volkoff, and F. Andreaux. 1991. Nature and Behavior of Organic-Matter in Soils under Natural Forest, and after Deforestation, Burning and Cultivation, near Manaus. Forest Ecology and Management 38:247-257.

Cerri, C.E.P., K. Coleman, D.S. Jenkinson, M. Bernoux, R. Victoria, and C.C. Cerri. 2003. Modeling soil carbon from forest and pasture ecosystems of Amazon, Brazil. Soil Science Society of America Journal 67:1879-1887.

de Moraes, J.F.L., F. Seyler, C.C. Cerri, and B. Volkoff. 1998. Land cover mapping and carbon pools estimates in Rondonia, Brazil. International Journal of Remote Sensing 19:921-934.

deMoraes, J.F.L., B. Volkoff, C.C. Cerri, and M. Bernoux. 1996. Soil properties under Amazon forest and changes due to pasture installation in Rondonia, Brazil. Geoderma 70:63-81.

Feigl, B.J., J. Melillo, and C.C. Cerri. 1995. Changes in the Origin and Quality of Soil Organic-Matter after Pasture Introduction in Rondonia (Brazil). Plant and Soil 175:21-29.

Fernandes, S.A.P., M. Bernoux, C.C. Cerri, B.J. Feigl, and M.C. Piccolo. 2002. Seasonal variation of soil chemical properties and CO2 and CH4 fluxes in unfertilized and P-fertilized pastures in an Ultisol of the Brazilian Amazon. Geoderma 107:227-241.

Martins, P., C.C. Cerri, B. Volkoff, F. Andreux, and A. Chauvel. 1991. Consequences of Clearing and Tillage on the Soil of a Natural Amazonian Ecosystem. Forest Ecology and Management 38:273-282.

Moraes, J.L., C.C. Cerri, J.M. Melillo, D. Kicklighter, C. Neill, D.L. Skole, and P.A. Steudler. 1995. Soil Carbon Stocks of the Brazilian Amazon Basin. Soil Science Society of America Journal 59:244-247.

Steudler, P.A., J.M. Melillo, B.J. Feigl, C. Neill, M.C. Piccolo, and C.C. Cerri. 1996. Consequence of forest-to-pasture conversion on CH4 fluxes in the Brazilian Amazon Basin. Journal of Geophysical Research-Atmospheres 101:18547-18554.