Document Detail


Changes in Size of Deforested Patches in the Brazilian Amazon.
MedLine Citation:
PMID:  22827325     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
  Different deforestation agents, such as small farmers and large agricultural businesses, create different spatial patterns of deforestation. We analyzed the proportion of deforestation associated with different-sized clearings in the Brazilian Amazon from 2002 through 2009. We used annual deforestation maps to determine total area deforested and the size distribution of deforested patches per year. The size distribution of deforested areas changed over time in a consistent, directional manner. Large clearings (>1000 ha) comprised progressively smaller amounts of total annual deforestation. The number of smaller clearings (6.25-50.00 ha) remained unchanged over time. Small clearings accounted for 73% of all deforestation in 2009, up from 30% in 2002, whereas the proportion of deforestation attributable to large clearings decreased from 13% to 3% between 2002 and 2009. Large clearings were concentrated in Mato Grosso, but also occurred in eastern Pará and in Rondônia. In 2002 large clearings accounted for 17%, 15%, and 10% of all deforestation in Mato Grosso, Pará, and Rondônia, respectively. Even in these states, where there is a highly developed agricultural business dominated by soybean production and cattle ranching, the proportional contribution of large clearings to total deforestation declined. By 2009 large clearings accounted for 2.5%, 3.5%, and 1% of all deforestation in Mato Grosso, Pará, and Rondônia, respectively. These changes in deforestation patch size are coincident with the implementation of new conservation policies by the Brazilian government, which suggests that these policies are not effectively reducing the number of small clearings in primary forest, whether these are caused by large landholders or smallholders, but have been more effective at reducing the frequency of larger clearings.
Authors:
Isabel M D Rosa; Carlos Souza; Robert M Ewers
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Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2012-7-24
Journal Detail:
Title:  Conservation biology : the journal of the Society for Conservation Biology     Volume:  -     ISSN:  1523-1739     ISO Abbreviation:  -     Publication Date:  2012 Jul 
Date Detail:
Created Date:  2012-7-25     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9882301     Medline TA:  Conserv Biol     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
©2012 Society for Conservation Biology.
Affiliation:
Imperial College of London, Silwood Park Campus, Buckhurst Road, Ascot SL5 7PY, United Kingdom Imazon - Amazon Institute of People and the Environment, Rua Domingos Marreiros, 2020, Fátima, CEP: 66.060-160, Belém, Pará, Brazil.
Vernacular Title:
Cambios en el Tamaño de Parches Deforestados en la Amazonía Brasileña.
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