Soil and vegetation carbon stocks after land-use changes in a seasonally dry tropical forest

• Published in: Geoderma Vol. 390; p. 114943
• Main Authors: Menezes, Rômulo Simões Cezar, Sales, Aldo Torres, Primo, Dário Costa, Albuquerque, Eliza Rosário Gomes Marinho de, Jesus, Kennedy Nascimento de, Pareyn, Frans Germain Corneel, Santana, Mônica da Silva, Santos, Uemeson José dos, Martins, Júlio César Rodrigues, Althoff, Tiago Diniz, Nascimento, Diego Marcelino do, Gouveia, Rafael Feitosa, Fernandes, Milton Marques, Loureiro, Diego Campana, Araújo Filho, José Coelho de, Giongo, Vanderlise, Duda, Gustavo Pereira, Alves, Bruno José Rodrigues, Ivo, Walane Maria Pereira de Mello, Andrade, Eunice Maia de, Pinto, Alexandre de Siqueira, Sampaio, Everardo Valadares de Sá Barretto
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-05-2021
• Subjects: Arid regions; Caatinga; Deforestation; Ecosystem C stocks; NE Brazil; Deforestation; Ecosystem C stocks; NE Brazil; Arid regions; Caatinga
• ISSN: 0016-7061; 1872-6259
• DOI: 10.1016/j.geoderma.2021.114943

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•Dense forest ecosystems store, on average, nearly 125 Mg ha−1 of C.•Changes to pastures and crop fields led to losses of up to 50% of ecosystem C stocks.•Open forest ecosystems store nearly 30% less C than dense forests.•C stocks between soil classes did not differ, with few exceptions.
The lack of robust scientific data still hinders estimates of soil and plant carbon (C) losses due to land-use changes in most dry tropical ecosystems. The present study investigated the effects of land-use and cover changes on total ecosystem C stocks in NE Brazil, aiming to quantify C losses after the removal of the native forest, known as Caatinga. The sampling design included the four main land-use/cover types (Dense Caatinga, Open Caatinga, Pastures and Crop fields) and the seven main soil classes (Arenosols, Acrisols, Regosols, Ferrasols, Luvisols, Planosols, and Leptosols), a combination that represents over 90% of the region. This design resulted in 192 sampling points (48 in each land-use), distributed proportionally to the area of occurrence of each soil class. In each sampling point, we determined C stocks in soil organic matter (SOM) and roots (to a depth of 1 m or rock layer), aboveground vegetation biomass (trees and herbs, separately), deadwood, and surface litter. Areas covered by Dense Caatinga store, on average, nearly 125 Mg ha−1 of C. Most of this C is stored in the soil organic matter (72.1%), followed by aboveground biomass (15.9%), belowground biomass (7.3%), deadwood (2.9%), litter (1.3%), and herbaceous biomass (0.5%). The substitution of Dense Caatinga to plant pastures and crop fields caused losses of >50% of ecosystem C stocks, reaching almost 65 Mg ha−1 of C, with nearly equal losses from the SOM and vegetation biomass compartments. Open Caatinga store nearly 30% less C than Dense Caatinga. Contrary to what was expected, the overall differences in C stocks between soil classes were not significant, with a few exceptions. We expect that the findings of this study will contribute to a more robust inventory of GHG emissions/removals due to land-use changes in NE Brazil and other dry tropical regions of the globe.