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1.
Proc Natl Acad Sci U S A ; 105(51): 20350-5, 2008 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19075224

RESUMO

Drainage of peatlands and deforestation have led to large-scale fires in equatorial Asia, affecting regional air quality and global concentrations of greenhouse gases. Here we used several sources of satellite data with biogeochemical and atmospheric modeling to better understand and constrain fire emissions from Indonesia, Malaysia, and Papua New Guinea during 2000-2006. We found that average fire emissions from this region [128 +/- 51 (1sigma) Tg carbon (C) year(-1), T = 10(12)] were comparable to fossil fuel emissions. In Borneo, carbon emissions from fires were highly variable, fluxes during the moderate 2006 El Niño more than 30 times greater than those during the 2000 La Niña (and with a 2000-2006 mean of 74 +/- 33 Tg C yr(-1)). Higher rates of forest loss and larger areas of peatland becoming vulnerable to fire in drought years caused a strong nonlinear relation between drought and fire emissions in southern Borneo. Fire emissions from Sumatra showed a positive linear trend, increasing at a rate of 8 Tg C year(-2) (approximately doubling during 2000-2006). These results highlight the importance of including deforestation in future climate agreements. They also imply that land manager responses to expected shifts in tropical precipitation may critically determine the strength of climate-carbon cycle feedbacks during the 21st century.


Assuntos
Clima , Conservação dos Recursos Naturais , Incêndios , Ásia , Monóxido de Carbono/análise , Secas , Ecossistema , Comunicações Via Satélite , Sphagnopsida
2.
J Environ Manage ; 82(1): 95-110, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16677754

RESUMO

Semi-structured focus group interviews were employed to examine factors that affect the likelihood that resource managers in southern Africa will use information on vegetation fires provided by two satellite-derived products: an active fire product and a burned area product. The two products are updated regularly and aim to deliver the state-of-the-art in the global monitoring of fires from satellite remote-sensing. Both products are derived from data transmitted by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors carried onboard NASA's Aqua and Terra satellites. The active fire product can be accessed for free via the internet and on media by users working anywhere in the world; the burned area product will be accessible in a similar manner in 2006. The MODIS fire products provide systematic, near-global coverage and are freely available; as such, they give resource managers new opportunities to obtain or supplement information they need to manage vegetation fires effectively. However, the availability of these products does not mean that resource managers will use them, and many other factors are involved. To understand factors that affect whether southern African resource managers will use the two products, two focus groups were held with members of the Southern African Fire Network (SAFNet) in Malawi, Africa, August 2004. Analysis of the group discussions reveals a number of factors that influence whether they will use the products. The qualitative, in depth nature of the group discussions revealed 12 main factors that influence product use; not least the low international internet bandwidths for African countries outside of South Africa. Analysis of the group discussions also suggests how the uptake of MODIS fire products by resource managers in southern Africa might be enhanced by affecting specific changes to how MODIS products are packaged and delivered.


Assuntos
Monitoramento Ambiental/métodos , Incêndios , Sistemas de Informação Geográfica , Comunicações Via Satélite , África Austral , Desastres/prevenção & controle , Monitoramento Ambiental/economia , Grupos Focais , Entrevistas como Assunto
3.
Science ; 303(5660): 1000-3, 2004 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-14963327

RESUMO

The ecology of Bornean rainforests is driven by El Niño-induced droughts that trigger synchronous fruiting among trees and bursts of faunal reproduction that sustain vertebrate populations. However, many of these species- and carbon-rich ecosystems have been destroyed by logging and conversion, which increasingly threaten protected areas. Our satellite, Geographic Information System, and field-based analyses show that from 1985 to 2001, Kalimantan's protected lowland forests declined by more than 56% (>29,000 square kilometers). Even uninhabited frontier parks are logged to supply international markets. "Protected" forests have become increasingly isolated and deforested and their buffer zones degraded. Preserving the ecological integrity of Kalimantan's rainforests requires immediate transnational management.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Árvores , Animais , Bornéu , Agricultura Florestal , Indústrias , Densidade Demográfica , Fatores de Tempo , Árvores/crescimento & desenvolvimento , Clima Tropical , Vertebrados , Madeira
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