Location: Sustainable Perennial Crops LaboratoryTitle: Soil classification and carbon storage in cacao agroforestry farming systems of Bahia, Brazil Author
Submitted to: Journal of Sustainable Forestry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/22/2013
Publication Date: 7/29/2013
Publication URL: http://handle.nal.usda.gov/10113/59036
Citation: Araujo, Q.R., Loureiro, G.A., Santana, S.O., Baligar, V.C. 2013. Soil classification and carbon storage in cacao agroforestry farming systems of Bahia, Brazil. Journal of Sustainable Forestry. 32:625-647. Interpretive Summary: In Atlantic rainforest region of Brazil, cacao is mainly grown under the agroforestry systems of management. Information on capacity of soils to store organic carbon in cacao- agroforestry systems is unavailable. Such information is essential for development of proper and adequate fertilization recommendation to achieve optimum yields of cacao. This study was aimed to quantify carbon stocks in soils under agroforestry systems of cacao management. In this paper we report that total storage of soil organic carbon in these soils was higher than in many of the non agroforestry soils of the region. Cacao growers could use such information in improving soil quality factors and designing optimum fertilizer management practices thereby reducing the cost of fertilizer inputs and increasing the sustainability and yield potentials of cacao grown under the agroforestry system of management.
Technical Abstract: Information concerning the classification of soils and their properties under cacao agroforestry systems of the Atlantic rain forest biome region in the Southeast of Bahia Brazil is largely unknown. Soil and climatic conditions in this region are favorable for high soil carbon storage. This study is aimed to classify soils under cocoa agroforestry and further, to quantify carbon stocks in these soil profiles. Soil classification was performed, and the amount of C stored was estimated, based on the thickness of the soil horizons, their bulk density and total organic carbon stored. In the sites studied under cacao, four general classes of soils were identified: Ultisols, Oxisols, Alfisols and Inceptisols. Carbon stock in these soil profiles showed wide variation, ranging from 719.24 Mg ha-1 to 2089.93 Mg ha-1. Carbon stocks in soil surface and subsurface layers in different agroforestry systems with cacao (cacao-cabruca, cacao x rubber tree and cacao x erythrina) were comparable; however, total storage of organic C in these soils was higher than expected, compared to values reported for the International Soil Reference and Information Centre (ISRIC), based on the FAO-UNESCO database, and were also higher than estimated regional soil data.