Premium
A large‐scale field assessment of carbon stocks in human‐modified tropical forests
Author(s) -
Berenguer Erika,
Ferreira Joice,
Gardner Toby Alan,
Aragão Luiz Eduardo Oliveira Cruz,
De Camargo Plínio Barbosa,
Cerri Carlos Eduardo,
Durigan Mariana,
Oliveira Raimundo Cosme De,
Vieira Ima Célia Guimarães,
Barlow Jos
Publication year - 2014
Publication title -
global change biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.146
H-Index - 255
eISSN - 1365-2486
pISSN - 1354-1013
DOI - 10.1111/gcb.12627
Subject(s) - environmental science , greenhouse gas , deforestation (computer science) , understory , logging , agroforestry , rainforest , carbon sequestration , climate change , tropics , secondary forest , carbon stock , tropical and subtropical dry broadleaf forests , ecology , forestry , geography , carbon dioxide , canopy , biology , programming language , computer science
Tropical rainforests store enormous amounts of carbon, the protection of which represents a vital component of efforts to mitigate global climate change. Currently, tropical forest conservation, science, policies, and climate mitigation actions focus predominantly on reducing carbon emissions from deforestation alone. However, every year vast areas of the humid tropics are disturbed by selective logging, understory fires, and habitat fragmentation. There is an urgent need to understand the effect of such disturbances on carbon stocks, and how stocks in disturbed forests compare to those found in undisturbed primary forests as well as in regenerating secondary forests. Here, we present the results of the largest field study to date on the impacts of human disturbances on above and belowground carbon stocks in tropical forests. Live vegetation, the largest carbon pool, was extremely sensitive to disturbance: forests that experienced both selective logging and understory fires stored, on average, 40% less aboveground carbon than undisturbed forests and were structurally similar to secondary forests. Edge effects also played an important role in explaining variability in aboveground carbon stocks of disturbed forests. Results indicate a potential rapid recovery of the dead wood and litter carbon pools, while soil stocks (0–30 cm) appeared to be resistant to the effects of logging and fire. Carbon loss and subsequent emissions due to human disturbances remain largely unaccounted for in greenhouse gas inventories, but by comparing our estimates of depleted carbon stocks in disturbed forests with Brazilian government assessments of the total forest area annually disturbed in the Amazon, we show that these emissions could represent up to 40% of the carbon loss from deforestation in the region. We conclude that conservation programs aiming to ensure the long‐term permanence of forest carbon stocks, such as REDD +, will remain limited in their success unless they effectively avoid degradation as well as deforestation.