1,659 results on '"Anderson LO"'
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2. Pamela Anderson lo sabe. Defensora de los derechos de los animales asegura que el sexo es mejor con veganos
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News, opinion and commentary - Abstract
By La Nación - Argentina Pamela Anderson y Brandon Lee en la Gala de amfAR en Cannes en el 2019 El veganismo era la otra gran revolución por venir (después [...]
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- 2021
3. Benedict Anderson: lo sguardo che ti spiazza
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d'Eramo, Marco, primary
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- 2016
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4. Quiere que Pamela Anderson lo despierte?
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- 2003
5. Deforestation falls but rise of wildfires continues degrading Brazilian Amazon forests.
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Mataveli G, Jones MW, Carmenta R, Sanchez A, Dutra DJ, Chaves M, de Oliveira G, Anderson LO, and Aragão LEOC
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- Brazil, Conservation of Natural Resources, Forests, Wildfires, Fires
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- 2024
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6. Overlooking vegetation loss outside forests imperils the Brazilian Cerrado and other non-forest biomes.
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da Conceição Bispo P, Picoli MCA, Marimon BS, Marimon Junior BH, Peres CA, Menor IO, Silva DE, de Figueiredo Machado F, Alencar AAC, de Almeida CA, Anderson LO, Aragão LEOC, Breunig FM, Bustamante M, Dalagnol R, Diniz-Filho JAF, Ferreira LG, Ferreira ME, Fisch G, Galvão LS, Giarolla A, Gomes AR, de Marco Junior P, Kuck TN, Lehmann CER, Lemes MR, Liesenberg V, Loyola R, Macedo MN, de Souza Mendes F, do Couto de Miranda S, Morton DC, Moura YM, Oldekop JA, Ramos-Neto MB, Rosan TM, Saatchi S, Sano EE, Segura-Garcia C, Shimbo JZ, Silva TSF, Trevisan DP, Zimbres B, Wiederkehr NC, and Silva-Junior CHL
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- Brazil, Forests, Ecosystem
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- 2024
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7. There's no smoke without fire!
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Anderson LO, Silva S, and Melo AWF
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- 2023
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8. Potential aboveground biomass increase in Brazilian Atlantic Forest fragments with climate change.
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Ferreira IJM, Campanharo WA, Fonseca MG, Escada MIS, Nascimento MT, Villela DM, Brancalion P, Magnago LFS, Anderson LO, Nagy L, and Aragão LEOC
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- Biomass, Brazil, Climate Change, Forests, Carbon, Tropical Climate, Ecosystem, Trees
- Abstract
Fragmented tropical forest landscapes preserve much of the remaining biodiversity and carbon stocks. Climate change is expected to intensify droughts and increase fire hazard and fire intensities, thereby causing habitat deterioration, and losses of biodiversity and carbon stock losses. Understanding the trajectories that these landscapes may follow under increased climate pressure is imperative for establishing strategies for conservation of biodiversity and ecosystem services. Here, we used a quantitative predictive modelling approach to project the spatial distribution of the aboveground biomass density (AGB) by the end of the 21st century across the Brazilian Atlantic Forest (AF) domain. To develop the models, we used the maximum entropy method with projected climate data to 2100, based on the Intergovernmental Panel on Climate Change Representative Concentration Pathway (RCP) 4.5 from the fifth Assessment Report. Our AGB models had a satisfactory performance (area under the curve > 0.75 and p value < .05). The models projected a significant increase of 8.5% in the total carbon stock. Overall, the projections indicated that 76.9% of the AF domain would have suitable climatic conditions for increasing biomass by 2100 considering the RCP 4.5 scenario, in the absence of deforestation. Of the existing forest fragments, 34.7% are projected to increase their AGB, while 2.6% are projected to have their AGB reduced by 2100. The regions likely to lose most AGB-up to 40% compared to the baseline-are found between latitudes 13° and 20° south. Overall, although climate change effects on AGB vary latitudinally for the 2071-2100 period under the RCP 4.5 scenario, our model indicates that AGB stocks can potentially increase across a large fraction of the AF. The patterns found here are recommended to be taken into consideration during the planning of restoration efforts, as part of climate change mitigation strategies in the AF and elsewhere in Brazil., (© 2023 John Wiley & Sons Ltd.)
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- 2023
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9. Brazilian Amazon indigenous territories under deforestation pressure.
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Silva-Junior CHL, Silva FB, Arisi BM, Mataveli G, Pessôa ACM, Carvalho NS, Reis JBC, Silva Júnior AR, Motta NACS, E Silva PVM, Ribeiro FD, Siqueira-Gay J, Alencar A, Saatchi S, Aragão LEOC, Anderson LO, and Melo M
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- Brazil, Ecosystem, Climate, Conservation of Natural Resources, Forests
- Abstract
Studies showed that Brazilian Amazon indigenous territories (ITs) are efficient models for preserving forests by reducing deforestation, fires, and related carbon emissions. Considering the importance of ITs for conserving socio-environmental and cultural diversity and the recent climb in the Brazilian Amazon deforestation, we used official remote sensing datasets to analyze deforestation inside and outside indigenous territories within Brazil's Amazon biome during the 2013-2021 period. Deforestation has increased by 129% inside ITs since 2013, followed by an increase in illegal mining areas. In 2019-2021, deforestation was 195% higher and 30% farther from the borders towards the interior of indigenous territories than in previous years (2013-2018). Furthermore, about 59% of carbon dioxide (CO
2 ) emissions within ITs in 2013-2021 (96 million tons) occurred in the last three years of analyzed years, revealing the magnitude of increasing deforestation to climate impacts. Therefore, curbing deforestation in indigenous territories must be a priority for the Brazilian government to secure these peoples' land rights, ensure the forests' protection and regulate the global climate., (© 2023. The Author(s).)- Published
- 2023
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10. The drivers and impacts of Amazon forest degradation.
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Lapola DM, Pinho P, Barlow J, Aragão LEOC, Berenguer E, Carmenta R, Liddy HM, Seixas H, Silva CVJ, Silva-Junior CHL, Alencar AAC, Anderson LO, Armenteras D, Brovkin V, Calders K, Chambers J, Chini L, Costa MH, Faria BL, Fearnside PM, Ferreira J, Gatti L, Gutierrez-Velez VH, Han Z, Hibbard K, Koven C, Lawrence P, Pongratz J, Portela BTT, Rounsevell M, Ruane AC, Schaldach R, da Silva SS, von Randow C, and Walker WS
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- Biodiversity, Carbon Cycle, Brazil, Carbon, Conservation of Natural Resources, Rainforest
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Approximately 2.5 × 10
6 square kilometers of the Amazon forest are currently degraded by fire, edge effects, timber extraction, and/or extreme drought, representing 38% of all remaining forests in the region. Carbon emissions from this degradation total up to 0.2 petagrams of carbon per year (Pg C year-1 ), which is equivalent to, if not greater than, the emissions from Amazon deforestation (0.06 to 0.21 Pg C year-1 ). Amazon forest degradation can reduce dry-season evapotranspiration by up to 34% and cause as much biodiversity loss as deforestation in human-modified landscapes, generating uneven socioeconomic burdens, mainly to forest dwellers. Projections indicate that degradation will remain a dominant source of carbon emissions independent of deforestation rates. Policies to tackle degradation should be integrated with efforts to curb deforestation and complemented with innovative measures addressing the disturbances that degrade the Amazon forest.- Published
- 2023
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11. Record-breaking fires in the Brazilian Amazon associated with uncontrolled deforestation.
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Mataveli G, de Oliveira G, Silva-Junior CHL, Stark SC, Carvalho N, Anderson LO, Gatti LV, and Aragão LEOC
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- Brazil, Conservation of Natural Resources, Fires
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- 2022
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12. Time to improve disaster preparedness in Brazil.
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Barbosa MLF, Haddad I, and Anderson LO
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- Brazil, Time Factors, Disaster Planning, Disasters prevention & control
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- 2022
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13. Brazil's mangroves: Natural carbon storage.
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da S Bezerra D, de Lima Santos A, Bezerra JS, Amaral S, Kampel M, Anderson LO, Mochel FR, Silva Nunes JL, de Araujo NA, Barreto LN, do S S Pinheiro M, Celeri MJ, Silva FB, Viegas AM, Manes S, Rodrigues TCS, Viegas JC, Souza UDV, Santos ALS, and Silva-Junior CHL
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- Brazil, Carbon Sequestration, Conservation of Natural Resources, Wetlands
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- 2022
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14. The 2020 Brazilian Pantanal fires.
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Pletsch MAJS, Silva Junior CHL, Penha TV, Körting TS, Silva MES, Pereira G, Anderson LO, and Aragão LEOC
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- Brazil, Fires
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- 2021
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15. Burning in southwestern Brazilian Amazonia, 2016-2019.
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Silva SSD, Oliveira I, Morello TF, Anderson LO, Karlokoski A, Brando PM, Melo AWF, Costa JGD, Souza FSC, Silva ISD, Nascimento ES, Pereira MP, Almeida MRN, Alencar A, Aragão LEOEC, Brown IF, Graça PMLA, and Fearnside PM
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- Brazil, Conservation of Natural Resources, Forests, Trees, Fires, Wildfires
- Abstract
Fire is one of the most powerful modifiers of the Amazonian landscape and knowledge about its drivers is needed for planning control and suppression. A plethora of factors may play a role in the annual dynamics of fire frequency, spanning the biophysical, climatic, socioeconomic and institutional dimensions. To uncover the main forces currently at play, we investigated the area burned in both forested and deforested areas in the outstanding case of Brazil's state of Acre, in southwestern Amazonia. We mapped burn scars in already-deforested areas and intact forest based on satellite images from the Landsat series analyzed between 2016 and 2019. The mapped burnings in already-deforested areas totalled 550,251 ha. In addition, we mapped three forest fires totaling 34,084 ha. Fire and deforestation were highly correlated, and the latter occurred mainly in federal government lands, with protected areas showing unprecedented forest fire levels in 2019. These results indicate that Acre state is under increased fire risk even during average rainfall years. The record fires of 2019 may continue if Brazil's ongoing softening of environmental regulations and enforcement is maintained. Acre and other Amazonian states must act quickly to avoid an upsurge of social and economic losses in the coming years., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
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- 2021
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16. Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests
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Wagner, FH, Hérault, B, Bonal, D, Stahl, C, Anderson, LO, Baker, TR, Sebastian Becker, G, Beeckman, H, Boanerges Souza, D, Cesar Botosso, P, Bowman, DMJS, Bräuning, A, Brede, B, Irving Brown, F, Julio Camarero, J, Camargo, PB, Cardoso, FCG, Carvalho, FA, Castro, W, Koloski Chagas, R, Chave, J, Chidumayo, EN, Clark, DA, Regina Capellotto Costa, F, Couralet, C, Henrique Da Silva Mauricio, P, Dalitz, H, Resende De Castro, V, Milani, JEDF, Consuelo De Oliveira, E, De Souza Arruda, L, Devineau, JL, Drew, DM, Dünisch, O, Durigan, G, Elifuraha, E, Fedele, M, Ferreira Fedele, L, Figueiredo Filho, A, Finger, CAG, César Franco, A, Jnior, LF, Galvão, F, Gebrekirstos, A, Gliniars, R, Maurício Lima De Alencastro Graça, P, Griffiths, AD, Grogan, J, Guan, K, Homeier, J, Raquel Kanieski, M, Khoon Kho, L, Koenig, J, Valerio Kohler, S, Krepkowski, J, Lemos-Filho, JP, Lieberman, D, Eugene Lieberman, M, Sergio Lisi, C, Longhi Santos, T, Ayala, JLL, Eijji Maeda, E, Malhi, Y, Maria, VRB, Marques, MCM, Marques, R, Maza Chamba, H, Mbwambo, L, Liana Lisboa Melgaço, K, Angela Mendivelso, H, Murphy, BP, O'Brien, JJ, F Oberbauer, S, Okada, N, Plissier, R, Prior, LD, Alejandro Roig, F, Ross, M, Rodrigo Rossatto, D, Rossi, V, Rowland, L, Rutishauser, E, Santana, H, Schulze, M, Selhorst, D, Rodrigues Silva, W, Silveira, M, Spannl, S, Swaine, MD, Toledo, JJ, Miranda Toledo, M, Toledo, M, and Toma, T
- Abstract
The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and 35 litter productivity measurements), their associated canopy photosynthetic capacity (enhanced vegetation index, EVI) and climate, we ask how carbon assimilation and aboveground allocation are related to climate seasonality in tropical forests and how they interact in the seasonal carbon cycle. We found that canopy photosynthetic capacity seasonality responds positively to precipitation when rainfall is
- Published
- 2016
17. Disentangling the contribution of multiple land covers to fires-mediated carbon emissions in Amazonia during the 2010 drought
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Anderson, LO, Aragão, LEOC, Gloor, EU, Arai, E, Adami, M, Saatchi, SS, Malhi, Y, Shimabukuro, YE, Barlow, J, Berenguer, E, and Duarte, V
- Abstract
In less than 15 years, the Amazon region experienced three major droughts. Links between droughts and fires have been demonstrated for the 1997/1998, 2005, and 2010 droughts. In 2010, emissions of 510 ± 120 Tg C were associated to fire alone in Amazonia. Existing approaches have, however, not yet disentangled the proportional contribution of multiple land cover sources to this total. We develop a novel integration of multisensor and multitemporal satellite-derived data on land cover, active fires, and burned area and an empirical model of fire-induced biomass loss to quantify the extent of burned areas and resulting biomass loss for multiple land covers in Mato Grosso (MT) state, southern Amazonia—the 2010 drought most impacted region. We show that 10.77% (96,855 km2) of MT burned. We estimated a gross carbon emission of 56.21 ± 22.5 Tg C from direct combustion of biomass, with an additional 29.4 ± 10 Tg C committed to be emitted in the following years due to dead wood decay. It is estimated that old-growth forest fires in the whole Brazilian Legal Amazon (BLA) have contributed to 14.81 Tg of C (11.75 Tg C to 17.87 Tg C) emissions to the atmosphere during the 2010 fire season, with an affected area of 27,555 km2. Total C loss from the 2010 fires in MT state and old-growth forest fires in the BLA represent, respectively, 77% (47% to 107%) and 86% (68.2% to 103%) of Brazil's National Plan on Climate Change annual target for Amazonia C emission reductions from deforestation.
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- 2015
18. Large carbon sink potential of secondary forests in the Brazilian Amazon to mitigate climate change.
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Heinrich VHA, Dalagnol R, Cassol HLG, Rosan TM, de Almeida CT, Silva Junior CHL, Campanharo WA, House JI, Sitch S, Hales TC, Adami M, Anderson LO, and Aragão LEOC
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- Algorithms, Biomass, Brazil, Conservation of Natural Resources methods, Ecosystem, Fires, Forestry, Geography, Models, Theoretical, Satellite Imagery methods, Trees growth & development, Trees metabolism, Carbon metabolism, Carbon Sequestration, Climate Change, Forests, Tropical Climate
- Abstract
Tropical secondary forests sequester carbon up to 20 times faster than old-growth forests. This rate does not capture spatial regrowth patterns due to environmental and disturbance drivers. Here we quantify the influence of such drivers on the rate and spatial patterns of regrowth in the Brazilian Amazon using satellite data. Carbon sequestration rates of young secondary forests (<20 years) in the west are ~60% higher (3.0 ± 1.0 Mg C ha
-1 yr-1 ) compared to those in the east (1.3 ± 0.3 Mg C ha-1 yr-1 ). Disturbances reduce regrowth rates by 8-55%. The 2017 secondary forest carbon stock, of 294 Tg C, could be 8% higher by avoiding fires and repeated deforestation. Maintaining the 2017 secondary forest area has the potential to accumulate ~19.0 Tg C yr-1 until 2030, contributing ~5.5% to Brazil's 2030 net emissions reduction target. Implementing legal mechanisms to protect and expand secondary forests whilst supporting old-growth conservation is, therefore, key to realising their potential as a nature-based climate solution.- Published
- 2021
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19. Improving the spatial-temporal analysis of Amazonian fires.
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Berenguer E, Carvalho N, Anderson LO, Aragão LEOC, França F, and Barlow J
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- Climate, Forests, Spatio-Temporal Analysis, Fires, Trees
- Abstract
There is a growing interest in Amazonian fires, accompanied by a substantial increase in research in the subject. Here, we list five common misunderstandings about Amazonian climate, vegetation, fires and the deforestation process to help to support future research., (© 2020 John Wiley & Sons Ltd.)
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- 2021
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20. The Brazilian Amazon deforestation rate in 2020 is the greatest of the decade.
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Silva Junior CHL, Pessôa ACM, Carvalho NS, Reis JBC, Anderson LO, and Aragão LEOC
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- Brazil, Trees, Conservation of Natural Resources, Forests
- Published
- 2021
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21. Copper-free click chemistry for dynamic in vivo imaging
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Pamela V. Chang, Jeremy M. Baskin, Julian A. Codelli, Carolyn R. Bertozzi, Jennifer A. Prescher, Scott T. Laughlin, Isaac A. Miller, Anderson Lo, and Nicholas J. Agard
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Glycan ,Time Factors ,Hydrocarbons, Fluorinated ,Cell Survival ,Stereochemistry ,Population ,Chemistry, Organic ,Hydrocarbons, Cyclic ,CHO Cells ,Catalysis ,Jurkat Cells ,Cricetulus ,Imaging, Three-Dimensional ,Polysaccharides ,Cricetinae ,Animals ,Humans ,education ,Copper-free click chemistry ,chemistry.chemical_classification ,education.field_of_study ,Multidisciplinary ,biology ,Biomolecule ,Proteins ,Biological Transport ,Endocytosis ,Cycloaddition ,Kinetics ,Bioorthogonal chemical reporter ,chemistry ,Physical Sciences ,biology.protein ,Click chemistry ,Biophysics ,Bioorthogonal chemistry ,Copper - Abstract
Dynamic imaging of proteins in live cells is routinely performed by using genetically encoded reporters, an approach that cannot be extended to other classes of biomolecules such as glycans and lipids. Here, we report a Cu-free variant of click chemistry that can label these biomolecules rapidly and selectively in living systems, overcoming the intrinsic toxicity of the canonical Cu-catalyzed reaction. The critical reagent, a substituted cyclooctyne, possesses ring strain and electron-withdrawing fluorine substituents that together promote the [3 + 2] dipolar cycloaddition with azides installed metabolically into biomolecules. This Cu-free click reaction possesses comparable kinetics to the Cu-catalyzed reaction and proceeds within minutes on live cells with no apparent toxicity. With this technique, we studied the dynamics of glycan trafficking and identified a population of sialoglycoconjugates with unexpectedly rapid internalization kinetics.
- Published
- 2007
22. A Comparative Study of Bioorthogonal Reactions with Azides
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Carolyn R. Bertozzi, Jeremy M. Baskin, Jennifer A. Prescher, Anderson Lo, and Nicholas J. Agard
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chemistry.chemical_classification ,Chemistry ,Biomolecule ,Context (language use) ,General Medicine ,Biochemistry ,Combinatorial chemistry ,Cycloaddition ,Bioorthogonal chemical reporter ,chemistry.chemical_compound ,Reagent ,Molecular Medicine ,Organic chemistry ,Azide ,Bioorthogonal chemistry ,Copper-free click chemistry - Abstract
Detection of metabolites and post-translational modifications can be achieved using the azide as a bioorthogonal chemical reporter. Once introduced into target biomolecules, either metabolically or through chemical modification, the azide can be tagged with probes using one of three highly selective reactions: the Staudinger ligation, the Cu(I)-catalyzed azide-alkyne cycloaddition, or the strain-promoted [3 + 2] cycloaddition. Here, we compared these chemistries in the context of various biological applications, including labeling of biomolecules in complex lysates and on live cell surfaces. The Cu(I)-catalyzed reaction was found to be most efficient for detecting azides in protein samples but was not compatible with live cells due to the toxicity of the reagents. Both the Staudinger ligation and the strain-promoted [3 + 2] cycloaddition using optimized cyclooctynes were effective for tagging azides on live cells. The best reagent for this application was dependent upon the specific structure of the azide...
- Published
- 2006
23. Persistent collapse of biomass in Amazonian forest edges following deforestation leads to unaccounted carbon losses.
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Silva Junior CHL, Aragão LEOC, Anderson LO, Fonseca MG, Shimabukuro YE, Vancutsem C, Achard F, Beuchle R, Numata I, Silva CA, Maeda EE, Longo M, and Saatchi SS
- Subjects
- Biomass, Carbon Sequestration, Forests, Carbon, Conservation of Natural Resources methods
- Abstract
Deforestation is the primary driver of carbon losses in tropical forests, but it does not operate alone. Forest fragmentation, a resulting feature of the deforestation process, promotes indirect carbon losses induced by edge effect. This process is not implicitly considered by policies for reducing carbon emissions in the tropics. Here, we used a remote sensing approach to estimate carbon losses driven by edge effect in Amazonia over the 2001 to 2015 period. We found that carbon losses associated with edge effect (947 Tg C) corresponded to one-third of losses from deforestation (2592 Tg C). Despite a notable negative trend of 7 Tg C year
-1 in carbon losses from deforestation, the carbon losses from edge effect remained unchanged, with an average of 63 ± 8 Tg C year-1 Carbon losses caused by edge effect is thus an additional unquantified flux that can counteract carbon emissions avoided by reducing deforestation, compromising the Paris Agreement's bold targets., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)- Published
- 2020
- Full Text
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24. Author Correction: Benchmark maps of 33 years of secondary forest age for Brazil.
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Silva Junior CHL, Heinrich VHA, Freire ATG, Broggio IS, Rosan TM, Doblas J, Anderson LO, Rousseau GX, Shimabukuro YE, Silva CA, House JI, and Aragão LEOC
- Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Published
- 2020
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25. Benchmark maps of 33 years of secondary forest age for Brazil.
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Silva Junior CHL, Heinrich VHA, Freire ATG, Broggio IS, Rosan TM, Doblas J, Anderson LO, Rousseau GX, Shimabukuro YE, Silva CA, House JI, and Aragão LEOC
- Abstract
The restoration and reforestation of 12 million hectares of forests by 2030 are amongst the leading mitigation strategies for reducing carbon emissions within the Brazilian Nationally Determined Contribution targets assumed under the Paris Agreement. Understanding the dynamics of forest cover, which steeply decreased between 1985 and 2018 throughout Brazil, is essential for estimating the global carbon balance and quantifying the provision of ecosystem services. To know the long-term increment, extent, and age of secondary forests is crucial; however, these variables are yet poorly quantified. Here we developed a 30-m spatial resolution dataset of the annual increment, extent, and age of secondary forests for Brazil over the 1986-2018 period. Land-use and land-cover maps from MapBiomas Project (Collection 4.1) were used as input data for our algorithm, implemented in the Google Earth Engine platform. This dataset provides critical spatially explicit information for supporting carbon emissions reduction, biodiversity, and restoration policies, enabling environmental science applications, territorial planning, and subsidizing environmental law enforcement.
- Published
- 2020
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26. Smoke pollution's impacts in Amazonia.
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de Oliveira G, Chen JM, Stark SC, Berenguer E, Moutinho P, Artaxo P, Anderson LO, and Aragão LEOC
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- Brazil epidemiology, COVID-19, Humans, Pandemics, Air Pollution, Conservation of Natural Resources, Coronavirus Infections epidemiology, Forests, Pneumonia, Viral epidemiology, Smoke
- Published
- 2020
- Full Text
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27. Application of remote sensing to understanding fire regimes and biomass burning emissions of the tropical Andes
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Oliveras, I, Anderson, LO, and Malhi, Y
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modis ,variability ,carbon ,Plant Ecology and Nature Conservation ,Remote sensing ,Environmental change ,PE&RC ,mortality ,tree ,burned-area ,southern africa ,amazonian forest ,deforestation ,Plantenecologie en Natuurbeheer ,biodiversity - Abstract
In the tropical Andes, there have been very few systematic studies aimed at understanding the biomass burning dynamics in the area. This paper seeks to advance on our understanding of burning regimes in this region, with the first detailed and comprehensive assessment of fire occurrence and the derived gross biomass burning emissions of an area of the Peruvian tropical Andes. We selected an area of 2.8 million hectares at altitudes over 2000 m. We analyzed fire occurrence over a 12 year period with three types of satellite data. Fire dynamics showed a large intra-annual and interannual variability, with most fires occurring May-October (the period coinciding with the dry season). Total area burned decreased with increasing rainfall until a given rainfall threshold beyond which no relationship was found. The estimated fire return interval (FRI) for the area is 37 years for grasslands, which is within the range reported for grasslands, and 65 years for forests, which is remarkably shorter than other reported FRI in tropical moist forests. The greatest contribution (60-70%, depending on the data source) to biomass burning emissions came from burned montane cloud forests (4.5 million Mg CO2 over the study period), despite accounting for only 7.4-10% of the total burned area. Gross aboveground biomass emissions (7.55 ± 2.14 Tg CO2; 0.43 ± 0.04 Tg CO; 24,012 ± 2685 Mg CH4 for the study area) were larger than previously reported for the tropical Andes. Key Points Fire regimes show high intra-annual and interannual variability MODIS fire products underestimate fire dynamics in the study area Estimated biomass burning emissions are 5.4-9.7 Tg CO2 for the period 2000-2011 ©2014. American Geophysical Union. All Rights Reserved.
- Published
- 2014
28. Impact of Embolization and Bakri Balloon Tamponade on Rate of Surgical Intervention for Postpartum Uterine Atony [5R]
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Parul Yadav, Glenn Markenson, Anderson Lo, and Peter St. Marie
- Subjects
Bakri balloon ,Uterine atony ,medicine.medical_specialty ,business.industry ,Intervention (counseling) ,medicine.medical_treatment ,Obstetrics and Gynecology ,Medicine ,Tamponade ,Embolization ,business ,medicine.disease ,Surgery - Published
- 2016
29. Copper-free click chemistry in living animals
- Author
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Carolyn R. Bertozzi, Pamela V. Chang, Ellen M. Sletten, Jeremy M. Baskin, Jennifer A. Prescher, Anderson Lo, Isaac A. Miller, and Nicholas J. Agard
- Subjects
Azides ,Glycoconjugate ,Context (language use) ,In Vitro Techniques ,Models, Biological ,Cyclooctanes ,Jurkat Cells ,Mice ,In vivo ,Animals ,Humans ,Reactivity (chemistry) ,Copper-free click chemistry ,Serum Albumin ,chemistry.chemical_classification ,Multidisciplinary ,Biomolecule ,Cell Membrane ,Hexosamines ,chemistry ,Biochemistry ,Cyclization ,Molecular Probes ,Physical Sciences ,Click chemistry ,Indicators and Reagents ,Bioorthogonal chemistry ,Glycoconjugates ,Copper ,Spleen ,Protein Binding - Abstract
Chemical reactions that enable selective biomolecule labeling in living organisms offer a means to probe biological processes in vivo. Very few reactions possess the requisite bioorthogonality, and, among these, only the Staudinger ligation between azides and triarylphosphines has been employed for direct covalent modification of biomolecules with probes in the mouse, an important model organism for studies of human disease. Here we explore an alternative bioorthogonal reaction, the 1,3-dipolar cycloaddition of azides and cyclooctynes, also known as “Cu-free click chemistry,” for labeling biomolecules in live mice. Mice were administered peracetylated N -azidoacetylmannosamine (Ac 4 ManNAz) to metabolically label cell-surface sialic acids with azides. After subsequent injection with cyclooctyne reagents, glycoconjugate labeling was observed on isolated splenocytes and in a variety of tissues including the intestines, heart, and liver, with no apparent toxicity. The cyclooctynes tested displayed various labeling efficiencies that likely reflect the combined influence of intrinsic reactivity and bioavailability. These studies establish Cu-free click chemistry as a bioorthogonal reaction that can be executed in the physiologically relevant context of a mouse.
- Published
- 2010
30. Effects of climate and land-use change scenarios on fire probability during the 21st century in the Brazilian Amazon.
- Author
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Fonseca MG, Alves LM, Aguiar APD, Arai E, Anderson LO, Rosan TM, Shimabukuro YE, and de Aragão LEOEC
- Subjects
- Brazil, Probability, Seasons, Climate Change, Conservation of Natural Resources
- Abstract
The joint and relative effects of future land-use and climate change on fire occurrence in the Amazon, as well its seasonal variation, are still poorly understood, despite its recognized importance. Using the maximum entropy method (MaxEnt), we combined regional land-use projections and climatic data from the CMIP5 multimodel ensemble to investigate the monthly probability of fire occurrence in the mid (2041-2070) and late (2071-2100) 21st century in the Brazilian Amazon. We found striking spatial variation in the fire relative probability (FRP) change along the months, with October showing the highest overall change. Considering climate only, the area with FRP ≥ 0.3 (a threshold chosen based on the literature) in October increases 6.9% by 2071-2100 compared to the baseline period under the representative concentration pathway (RCP) 4.5 and 27.7% under the RCP 8.5. The best-case land-use scenario ("Sustainability") alone causes a 10.6% increase in the area with FRP ≥ 0.3, while the worse-case land-use scenario ("Fragmentation") causes a 73.2% increase. The optimistic climate-land-use projection (Sustainability and RCP 4.5) causes a 21.3% increase in the area with FRP ≥ 0.3 in October by 2071-2100 compared to the baseline period. In contrast, the most pessimistic climate-land-use projection (Fragmentation and RCP 8.5) causes a widespread increase in FRP (113.5% increase in the area with FRP ≥ 0.3), and prolongs the fire season, displacing its peak. Combining the Sustainability land-use and RCP 8.5 scenarios causes a 39.1% increase in the area with FRP ≥ 0.3. We conclude that avoiding the regress on land-use governance in the Brazilian Amazon (i.e., decrease in the extension and level of conservation of the protected areas, reduced environmental laws enforcement, extensive road paving, and increased deforestation) would substantially mitigate the effects of climate change on fire probability, even under the most pessimistic RCP 8.5 scenario., (© 2019 John Wiley & Sons Ltd.)
- Published
- 2019
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31. Drought-induced Amazonian wildfires instigate a decadal-scale disruption of forest carbon dynamics.
- Author
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Silva CVJ, Aragão LEOC, Barlow J, Espirito-Santo F, Young PJ, Anderson LO, Berenguer E, Brasil I, Foster Brown I, Castro B, Farias R, Ferreira J, França F, Graça PMLA, Kirsten L, Lopes AP, Salimon C, Scaranello MA, Seixas M, Souza FC, and Xaud HAM
- Subjects
- Biomass, Brazil, Seasons, Trees growth & development, Wood analysis, Carbon Cycle, Droughts, Forests, Wildfires
- Abstract
Drought-induced wildfires have increased in frequency and extent over the tropics. Yet, the long-term (greater than 10 years) responses of Amazonian lowland forests to fire disturbance are poorly known. To understand post-fire forest biomass dynamics, and to assess the time required for fire-affected forests to recover to pre-disturbance levels, we combined 16 single with 182 multiple forest census into a unique large-scale and long-term dataset across the Brazilian Amazonia. We quantified biomass, mortality and wood productivity of burned plots along a chronosequence of up to 31 years post-fire and compared to surrounding unburned plots measured simultaneously. Stem mortality and growth were assessed among functional groups. At the plot level, we found that fire-affected forests have biomass levels 24.8 ± 6.9% below the biomass value of unburned control plots after 31 years. This lower biomass state results from the elevated levels of biomass loss through mortality, which is not sufficiently compensated for by wood productivity (incremental growth + recruitment). At the stem level, we found major changes in mortality and growth rates up to 11 years post-fire. The post-fire stem mortality rates exceeded unburned control plots by 680% (i.e. greater than 40 cm diameter at breast height (DBH); 5-8 years since last fire) and 315% (i.e. greater than 0.7 g cm
-3 wood density; 0.75-4 years since last fire). Our findings indicate that wildfires in humid tropical forests can significantly reduce forest biomass for decades by enhancing mortality rates of all trees, including large and high wood density trees, which store the largest amount of biomass in old-growth forests. This assessment of stem dynamics, therefore, demonstrates that wildfires slow down or stall the post-fire recovery of Amazonian forests.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'., (© 2018 The Author(s).)- Published
- 2018
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32. Vulnerability of Amazonian forests to repeated droughts.
- Author
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Anderson LO, Ribeiro Neto G, Cunha AP, Fonseca MG, Mendes de Moura Y, Dalagnol R, Wagner FH, and de Aragão LEOEC
- Subjects
- Brazil, Climate Change, Photosynthesis, Satellite Imagery, Droughts, El Nino-Southern Oscillation, Forests, Trees physiology
- Abstract
Extreme droughts have been recurrent in the Amazon over the past decades, causing socio-economic and environmental impacts. Here, we investigate the vulnerability of Amazonian forests, both undisturbed and human-modified, to repeated droughts. We defined vulnerability as a measure of (i) exposure, which is the degree to which these ecosystems were exposed to droughts, and (ii) its sensitivity, measured as the degree to which the drought has affected remote sensing-derived forest greenness. The exposure was calculated by assessing the meteorological drought, using the standardized precipitation index (SPI) and the maximum cumulative water deficit (MCWD), which is related to vegetation water stress, from 1981 to 2016. The sensitivity was assessed based on the enhanced vegetation index anomalies (AEVI), derived from the newly available Moderate Resolution Imaging Spectroradiometer (MODIS)/Multi-Angle Implementation of Atmospheric Correction algorithm (MAIAC) product, from 2003 to 2016, which is indicative of forest's photosynthetic capacity. We estimated that 46% of the Brazilian Amazon biome was under severe to extreme drought in 2015/2016 as measured by the SPI, compared with 16% and 8% for the 2009/2010 and 2004/2005 droughts, respectively. The most recent drought (2015/2016) affected the largest area since the drought of 1981. Droughts tend to increase the variance of the photosynthetic capacity of Amazonian forests as based on the minimum and maximum AEVI analysis. However, the area showing a reduction in photosynthetic capacity prevails in the signal, reaching more than 400 000 km
2 of forests, four orders of magnitude larger than areas with AEVI enhancement. Moreover, the intensity of the negative AEVI steadily increased from 2005 to 2016. These results indicate that during the analysed period drought impacts were being exacerbated through time. Forests in the twenty-first century are becoming more vulnerable to droughts, with larger areas intensively and negatively responding to water shortage in the region.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'., (© 2018 The Author(s).)- Published
- 2018
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33. Metabolic labeling of glycans with azido sugars for visualization and glycoproteomics
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Scott T, Laughlin, Nicholas J, Agard, Jeremy M, Baskin, Isaac S, Carrico, Pamela V, Chang, Anjali S, Ganguli, Matthew J, Hangauer, Anderson, Lo, Jennifer A, Prescher, and Carolyn R, Bertozzi
- Subjects
Proteomics ,Azides ,Mice ,Molecular Structure ,Proteome ,Polysaccharides ,Molecular Sequence Data ,Carbohydrate Conformation ,Animals ,Indicators and Reagents ,Cells, Cultured ,Glycoproteins - Abstract
The staggering complexity of glycans renders their analysis extraordinarily difficult, particularly in living systems. A recently developed technology, termed metabolic oligosaccharide engineering, enables glycan labeling with probes for visualization in cells and living animals, and enrichment of specific glycoconjugate types for proteomic analysis. This technology involves metabolic labeling of glycans with a specifically reactive, abiotic functional group, the azide. Azido sugars are fed to cells and integrated by the glycan biosynthetic machinery into various glycoconjugates. The azido sugars are then covalently tagged, either ex vivo or in vivo, using one of two azide-specific chemistries: the Staudinger ligation, or the strain-promoted [3+2] cycloaddition. These reactions can be used to tag glycans with imaging probes or epitope tags, thus enabling the visualization or enrichment of glycoconjugates. Applications to noninvasive imaging and glycoproteomic analyses are discussed.
- Published
- 2006
34. Fraction images for monitoring intra-annual phenology of different vegetation physiognomies in Amazonia
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Anderson, LO, Aragão, LOC, Shimabukuro, YE, Almeida, S, Huete, A, Anderson, LO, Aragão, LOC, Shimabukuro, YE, Almeida, S, and Huete, A
- Abstract
In this study we investigate the potential of fraction images derived from a linear spectral mixture model to detect vegetation phenology in Amazonia, and evaluate their relationships with the Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indices. Time series ofMODIS 250-m data over three contrasting land cover types in the Amazon were used in conjunction with rainfall data, a land covermap and a forest inventory survey to support the interpretation of our findings. Each vegetation physiognomy was characterized by a particular intra-annual variability detected by a combination of the fraction images. Both vegetation and shade fractions were important to evaluate the seasonality of the open tropical forest (OTF). The association of these results with forest inventory data and the literature suggests that Enhanced Vegetation Index (EVI) and vegetation fraction images are sensitive to structural changes in the canopy of OTF. In cerrado grassland (CG) the phenology was better characterized by combined soil and vegetation fractions. Soybean (SB) areas were characterized by the highest ranges in the vegetation and soil fraction images. Vegetation fraction and vegetation indices for the OTF showed a significant positive relationship with EVI but not with Normalized Difference Vegetation Index (NDVI). Significant relationships for vegetation fraction and vegetation indices were also found for the CG and soybean areas. In contrast to vegetation index approaches to monitoring phenology, fraction images provide additional information that allows amore comprehensive exploration of the spectral and structural changes in vegetation formations. © 2011 Taylor & Francis.
- Published
- 2011
35. 21st Century drought-related fires counteract the decline of Amazon deforestation carbon emissions.
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Aragão LEOC, Anderson LO, Fonseca MG, Rosan TM, Vedovato LB, Wagner FH, Silva CVJ, Silva Junior CHL, Arai E, Aguiar AP, Barlow J, Berenguer E, Deeter MN, Domingues LG, Gatti L, Gloor M, Malhi Y, Marengo JA, Miller JB, Phillips OL, and Saatchi S
- Abstract
Tropical carbon emissions are largely derived from direct forest clearing processes. Yet, emissions from drought-induced forest fires are, usually, not included in national-level carbon emission inventories. Here we examine Brazilian Amazon drought impacts on fire incidence and associated forest fire carbon emissions over the period 2003-2015. We show that despite a 76% decline in deforestation rates over the past 13 years, fire incidence increased by 36% during the 2015 drought compared to the preceding 12 years. The 2015 drought had the largest ever ratio of active fire counts to deforestation, with active fires occurring over an area of 799,293 km
2 . Gross emissions from forest fires (989 ± 504 Tg CO2 year-1 ) alone are more than half as great as those from old-growth forest deforestation during drought years. We conclude that carbon emission inventories intended for accounting and developing policies need to take account of substantial forest fire emissions not associated to the deforestation process.- Published
- 2018
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36. Climatic and anthropogenic drivers of northern Amazon fires during the 2015-2016 El Niño event.
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Fonseca MG, Anderson LO, Arai E, Shimabukuro YE, Xaud HAM, Xaud MR, Madani N, Wagner FH, and Aragão LEOC
- Subjects
- Brazil, Droughts, Seasons, Time Factors, Climate Change, El Nino-Southern Oscillation, Forests, Wildfires
- Abstract
The strong El Niño Southern Oscillation (ENSO) event that occurred in 2015-2016 caused extreme drought in the northern Brazilian Amazon, especially in the state of Roraima, increasing fire occurrence. Here we map the extent of precipitation and fire anomalies and quantify the effects of climatic and anthropogenic drivers on fire occurrence during the 2015-2016 dry season (from December 2015 to March 2016) in the state of Roraima. To achieve these objectives we first estimated the spatial pattern of precipitation anomalies, based on long-term data from the TRMM (Tropical Rainfall Measuring Mission), and the fire anomaly, based on MODIS (Moderate Resolution Imaging Spectroradiometer) active fire detections during the referred period. Then, we integrated climatic and anthropogenic drivers in a Maximum Entropy (MaxEnt) model to quantify fire probability, assessing (1) the model accuracy during the 2015-2016 and the 2016-2017 dry seasons; (2) the relative importance of each predictor variable on the model predictive performance; and (3) the response curves, showing how each environmental variable affects the fire probability. Approximately 59% (132,900 km
2 ) of the study area was exposed to precipitation anomalies ≤-1 standard deviation (SD) in January and ~48% (~106,800 km2 ) in March. About 38% (86,200 km2 ) of the study area experienced fire anomalies ≥1 SD in at least one month between December 2015 and March 2016. The distance to roads and the direct ENSO effect on fire occurrence were the two most influential variables on model predictive performance. Despite the improvement of governmental actions of fire prevention and firefighting in Roraima since the last intense ENSO event (1997-1998), we show that fire still gets out of control in the state during extreme drought events. Our results indicate that if no prevention actions are undertaken, future road network expansion and a climate-induced increase in water stress will amplify fire occurrence in the northern Amazon, even in its humid dense forests. As an additional outcome of our analysis, we conclude that the model and the data we used may help to guide on-the-ground fire-prevention actions and firefighting planning and therefore minimize fire-related ecosystems degradation, economic losses and carbon emissions in Roraima., (© 2017 by the Ecological Society of America.)- Published
- 2017
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37. Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.
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Devisscher T, Anderson LO, Aragão LE, Galván L, and Malhi Y
- Subjects
- Bolivia, Calibration, Ecosystem, Models, Theoretical, Risk, Climate, Droughts, Fires
- Abstract
Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can inform fire and land management decisions in the Chiquitania and other tropical forest landscapes to better anticipate and manage large wildfires in the future., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2016
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38. Toward an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity.
- Author
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Bustamante MM, Roitman I, Aide TM, Alencar A, Anderson LO, Aragão L, Asner GP, Barlow J, Berenguer E, Chambers J, Costa MH, Fanin T, Ferreira LG, Ferreira J, Keller M, Magnusson WE, Morales-Barquero L, Morton D, Ometto JP, Palace M, Peres CA, Silvério D, Trumbore S, and Vieira IC
- Subjects
- Climate Change, Conservation of Natural Resources, Ecosystem, Forestry methods, Models, Theoretical, Tropical Climate, Biodiversity, Carbon, Carbon Cycle, Forests
- Abstract
Tropical forests harbor a significant portion of global biodiversity and are a critical component of the climate system. Reducing deforestation and forest degradation contributes to global climate-change mitigation efforts, yet emissions and removals from forest dynamics are still poorly quantified. We reviewed the main challenges to estimate changes in carbon stocks and biodiversity due to degradation and recovery of tropical forests, focusing on three main areas: (1) the combination of field surveys and remote sensing; (2) evaluation of biodiversity and carbon values under a unified strategy; and (3) research efforts needed to understand and quantify forest degradation and recovery. The improvement of models and estimates of changes of forest carbon can foster process-oriented monitoring of forest dynamics, including different variables and using spatially explicit algorithms that account for regional and local differences, such as variation in climate, soil, nutrient content, topography, biodiversity, disturbance history, recovery pathways, and socioeconomic factors. Generating the data for these models requires affordable large-scale remote-sensing tools associated with a robust network of field plots that can generate spatially explicit information on a range of variables through time. By combining ecosystem models, multiscale remote sensing, and networks of field plots, we will be able to evaluate forest degradation and recovery and their interactions with biodiversity and carbon cycling. Improving monitoring strategies will allow a better understanding of the role of forest dynamics in climate-change mitigation, adaptation, and carbon cycle feedbacks, thereby reducing uncertainties in models of the key processes in the carbon cycle, including their impacts on biodiversity, which are fundamental to support forest governance policies, such as Reducing Emissions from Deforestation and Forest Degradation., (© 2015 John Wiley & Sons Ltd.)
- Published
- 2016
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39. Disentangling the contribution of multiple land covers to fire-mediated carbon emissions in Amazonia during the 2010 drought.
- Author
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Anderson LO, Aragão LE, Gloor M, Arai E, Adami M, Saatchi SS, Malhi Y, Shimabukuro YE, Barlow J, Berenguer E, and Duarte V
- Abstract
In less than 15 years, the Amazon region experienced three major droughts. Links between droughts and fires have been demonstrated for the 1997/1998, 2005, and 2010 droughts. In 2010, emissions of 510 ± 120 Tg C were associated to fire alone in Amazonia. Existing approaches have, however, not yet disentangled the proportional contribution of multiple land cover sources to this total. We develop a novel integration of multisensor and multitemporal satellite-derived data on land cover, active fires, and burned area and an empirical model of fire-induced biomass loss to quantify the extent of burned areas and resulting biomass loss for multiple land covers in Mato Grosso (MT) state, southern Amazonia-the 2010 drought most impacted region. We show that 10.77% (96,855 km
2 ) of MT burned. We estimated a gross carbon emission of 56.21 ± 22.5 Tg C from direct combustion of biomass, with an additional 29.4 ± 10 Tg C committed to be emitted in the following years due to dead wood decay. It is estimated that old-growth forest fires in the whole Brazilian Legal Amazon (BLA) have contributed to 14.81 Tg of C (11.75 Tg C to 17.87 Tg C) emissions to the atmosphere during the 2010 fire season, with an affected area of 27,555 km2 . Total C loss from the 2010 fires in MT state and old-growth forest fires in the BLA represent, respectively, 77% (47% to 107%) and 86% (68.2% to 103%) of Brazil's National Plan on Climate Change annual target for Amazonia C emission reductions from deforestation.- Published
- 2015
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40. Environmental change and the carbon balance of Amazonian forests.
- Author
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Aragão LE, Poulter B, Barlow JB, Anderson LO, Malhi Y, Saatchi S, Phillips OL, and Gloor E
- Subjects
- Conservation of Natural Resources, Environmental Monitoring, Environmental Policy, Carbon Cycle, Climate Change, Forests, Plants metabolism
- Abstract
Extreme climatic events and land-use change are known to influence strongly the current carbon cycle of Amazonia, and have the potential to cause significant global climate impacts. This review intends to evaluate the effects of both climate and anthropogenic perturbations on the carbon balance of the Brazilian Amazon and to understand how they interact with each other. By analysing the outputs of the Intergovernmental Panel for Climate Change (IPCC) Assessment Report 4 (AR4) model ensemble, we demonstrate that Amazonian temperatures and water stress are both likely to increase over the 21st Century. Curbing deforestation in the Brazilian Amazon by 62% in 2010 relative to the 1990s mean decreased the Brazilian Amazon's deforestation contribution to global land use carbon emissions from 17% in the 1990s and early 2000s to 9% by 2010. Carbon sources in Amazonia are likely to be dominated by climatic impacts allied with forest fires (48.3% relative contribution) during extreme droughts. The current net carbon sink (net biome productivity, NBP) of +0.16 (ranging from +0.11 to +0.21) Pg C year(-1) in the Brazilian Amazon, equivalent to 13.3% of global carbon emissions from land-use change for 2008, can be negated or reversed during drought years [NBP = -0.06 (-0.31 to +0.01) Pg C year(-1) ]. Therefore, reducing forest fires, in addition to reducing deforestation, would be an important measure for minimizing future emissions. Conversely, doubling the current area of secondary forests and avoiding additional removal of primary forests would help the Amazonian gross forest sink to offset approximately 42% of global land-use change emissions. We conclude that a few strategic environmental policy measures are likely to strengthen the Amazonian net carbon sink with global implications. Moreover, these actions could increase the resilience of the net carbon sink to future increases in drought frequency., (© 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.)
- Published
- 2014
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41. Bayesian spatio-temporal modeling of the Brazilian fire spots between 2011 and 2022.
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Pimentel, Jonatha Sousa, Bulhões, Rodrigo S, and Rodrigues, Paulo Canas
- Subjects
ATMOSPHERIC temperature ,WIND speed ,HUMAN behavior ,WILDFIRE risk ,QUALITY of life ,NATURAL disasters ,WILDFIRES - Abstract
Wildfires are among the most common natural disasters in many world regions and actively impact life quality. These events have become frequent due to climate change, other local policies, and human behavior. Fire spots are areas where the temperature is significantly higher than in the surrounding areas and are often used to identify wildfires. This study considers the historical data with the geographical locations of all the "fire spots" detected by the reference satellites covering the Brazilian territory between January 2011 and December 2022, comprising more than 2.2 million fire spots. This data was modeled with a spatio-temporal generalized linear mixed model for areal unit data, whose inferences about its parameters are made in a Bayesian framework and use meteorological variables (precipitation, air temperature, humidity, and wind speed) and a human variable (land-use transition and occupation) as covariates. The meteorological variables humidity and air temperature showed the most significant impact on the number of fire spots for each of the six Brazilian biomes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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42. Increasing frequency and intensity of the most extreme wildfires on Earth.
- Author
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Cunningham, Calum X., Williamson, Grant J., and Bowman, David M. J. S.
- Published
- 2024
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43. Assessing four decades of fire behavior dynamics in the Cerrado biome (1985 to 2022).
- Author
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da Silva Arruda, Vera Laísa, Alencar, Ane Auxiliadora Costa, de Carvalho Júnior, Osmar Abílio, de Figueiredo Ribeiro, Fernanda, de Arruda, Filipe Viegas, Conciani, Dhemerson Estevão, da Silva, Wallace Vieira, and Shimbo, Julia Zanin
- Abstract
Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
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44. Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements.
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Gatti LV, Gloor M, Miller JB, Doughty CE, Malhi Y, Domingues LG, Basso LS, Martinewski A, Correia CS, Borges VF, Freitas S, Braz R, Anderson LO, Rocha H, Grace J, Phillips OL, and Lloyd J
- Subjects
- Biomass, Biota, Brazil, Carbon Dioxide analysis, Carbon Monoxide analysis, Fires statistics & numerical data, Fresh Water analysis, Photosynthesis, Rain, Seasons, Trees metabolism, Tropical Climate, Atmosphere chemistry, Carbon Cycle, Droughts statistics & numerical data
- Abstract
Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought.
- Published
- 2014
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45. Persistent effects of a severe drought on Amazonian forest canopy.
- Author
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Saatchi S, Asefi-Najafabady S, Malhi Y, Aragão LE, Anderson LO, Myneni RB, and Nemani R
- Subjects
- Brazil, Fires, Geographic Mapping, Microwaves, Radar, Time Factors, Tropical Climate, Droughts, Trees growth & development
- Abstract
Recent Amazonian droughts have drawn attention to the vulnerability of tropical forests to climate perturbations. Satellite and in situ observations have shown an increase in fire occurrence during drought years and tree mortality following severe droughts, but to date there has been no assessment of long-term impacts of these droughts across landscapes in Amazonia. Here, we use satellite microwave observations of rainfall and canopy backscatter to show that more than 70 million hectares of forest in western Amazonia experienced a strong water deficit during the dry season of 2005 and a closely corresponding decline in canopy structure and moisture. Remarkably, and despite the gradual recovery in total rainfall in subsequent years, the decrease in canopy backscatter persisted until the next major drought, in 2010. The decline in backscatter is attributed to changes in structure and water content associated with the forest upper canopy. The persistence of low backscatter supports the slow recovery (>4 y) of forest canopy structure after the severe drought in 2005. The result suggests that the occurrence of droughts in Amazonia at 5-10 y frequency may lead to persistent alteration of the forest canopy.
- Published
- 2013
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46. Flood hazard analysis and risk assessment using remote sensing, GIS, and AHP techniques: a case study of the Gidabo Watershed, main Ethiopian Rift, Ethiopia.
- Author
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Diriba, Dechasa, Takele, Tariku, Karuppannan, Shankar, and Husein, Musa
- Published
- 2024
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47. Remote sensing detection of droughts in Amazonian forest canopies.
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Anderson LO, Malhi Y, Aragão LE, Ladle R, Arai E, Barbier N, and Phillips O
- Subjects
- Brazil, Rain, Seasons, Sunlight, Time Factors, Water, Droughts, Plant Leaves physiology, Satellite Communications, Trees physiology
- Abstract
*Remote sensing data are a key tool to assess large forested areas, where limitations such as accessibility and lack of field measurements are prevalent. Here, we have analysed datasets from moderate resolution imaging spectroradiometer (MODIS) satellite measurements and field data to assess the impacts of the 2005 drought in Amazonia. *We combined vegetation indices (VI) and climatological variables to evaluate the spatiotemporal patterns associated with the 2005 drought, and explore the relationships between remotely-sensed indices and forest inventory data on tree mortality. *There were differences in results based on c4 and c5 MODIS products. C5 VI showed no spatial relationship with rainfall or aerosol optical depth; however, distinct regions responded significantly to the increased radiation in 2005. The increase in the Enhanced VI (EVI) during 2005 showed a significant positive relationship (P < 0.07) with the increase of tree mortality. By contrast, the normalized difference water index (NDWI) exhibited a significant negative relationship (P < 0.09) with tree mortality. *Previous studies have suggested that the increase in EVI during the 2005 drought was associated with a positive response of forest photosynthesis to changes in the radiation income. We discuss the evidence that this increase could be related to structural changes in the canopy.
- Published
- 2010
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48. Regional ecosystem structure and function: ecological insights from remote sensing of tropical forests.
- Author
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Chambers JQ, Asner GP, Morton DC, Anderson LO, Saatchi SS, Espírito-Santo FD, Palace M, and Souza C Jr
- Subjects
- Humans, South America, Ecology methods, Ecosystem, Trees physiology, Tropical Climate
- Abstract
Ecological studies in tropical forests have long been plagued by difficulties associated with sampling the crowns of large canopy trees and large inaccessible regions, such as the Amazon basin. Recent advances in remote sensing have overcome some of these obstacles, enabling progress towards tackling difficult ecological problems. Breakthroughs have helped transform the dialog between ecology and remote sensing, generating new regional perspectives on key environmental gradients and species assemblages with ecologically relevant measures such as canopy nutrient and moisture content, crown area, leaf-level drought responses, woody tissue and surface litter abundance, phenological patterns, and land-cover transitions. Issues that we address here include forest response to altered precipitation regimes, regional disturbance and land-use patterns, invasive species and landscape carbon balance.
- Published
- 2007
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49. Is there a relationship between forest fires and deforestation in the Brazilian Amazon?
- Author
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Furtado Lima, Cássio, Pereira Torres, Fillipe Tamiozzo, Minette, Luciano José, Araujo Lima, Fernanda, Andrade Lima, Roldão Carlos, Keisuke Sato, Michel, Araújo Silva, Arthur, Leão Said Schettini, Bruno, Costa Ferreira, Francisco de Assis, and Lima Machado, Mateus Xavier
- Subjects
FOREST fires ,DEFORESTATION ,FOREST fire prevention & control ,WILDFIRE prevention ,FOREST dynamics ,FOREST reserves ,CITIES & towns - Abstract
The Brazilian Legal Amazon is an extensive territory in which different factors influence the dynamics of forest fires. Currently, the Brazilian government has two tools in the public domain and free of charge, PRODES and BDQueimadas, to monitor and make decisions to combat deforestation and forest fires. This work aimed to evaluate and correlate the forest fire alerts and deforestation in the Amazon Forest in the state of Pará. The analyses were based on carrying out a diagnosis of forest fires and deforestation; the behavior of forest fires and deforestation over the last twenty years; the statistical relationship between deforestation and forest fires and their spatialization. This work identified that Pará is the state in the Legal Amazon with the highest occurrence of forest fires and deforestation. Deforestation in the four-year period Jan/2003-Dec/2006 showed a higher rate compared to the four-year periods Jan/2011-Dec/2018. A high correlation was found between forest fire alerts and increases in deforestation. There is a spatial relationship between cities with greater increases in deforestation and high numbers of fire alerts. In relation to the occurrence of forest fires and deforestation, the south of the state was the most critical region and the north had lower rates. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Variability of Middle East springtime dust events between 2011 and 2022.
- Author
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Broomandi, Parya, Galán-Madruga, David, Satyanaga, Alfrendo, Hamidi, Mehdi, Ledari, Dorna Gholamzade, Fathian, Aram, Sarvestan, Rasoul, Janatian, Nasime, Jahanbakhshi, Ali, Bagheri, Mehdi, Karaca, Ferhat, Al-Dousari, Ali, and Kim, Jong Ryeol
- Abstract
The Middle East frontal sand and dust storms (SDS) occur in non-summer seasons, and represent an important phenomenon of this region's climate. Among the mentioned type, spring SDS are the most common. Trend analysis was used in the current study to investigate the spatial-temporal variability of springtime dust events in the Middle East using synoptic station observation from 2011 to 2022. The plausible changes in some controlling factors of dust activity at selected important dust sources in the Middle East were also studied during this time period. Our results showed a statistically significant spike in springtime dust events across the Middle East, particularly in May 2022. To evaluate the relative importance of controlling factors, the applied feature of importance analysis using random forest (RF) showed the higher relative importance of topsoil layer wetness, surface soil temperature, and surface wind speed in dust activity over the Middle East between 2011 and 2022. Long-term trend analysis of topsoil moisture and temperature, using the Mann-Kendall trend test, showed a decrease in soil moisture and an increase in soil temperature in some selected important dust sources in the Middle East. Moreover, our predictions using ARIMA models showed a high tendency to dust activities in selected major dust origins (domain 2 and domain 5) with a statistically significant increase (p-value < 0.05) between 2023 and 2029. Observed spatial and temporal changes within SDS hotspots can act as the first step to build up for the first time an SDS precise intensity scale, as well as establishing an SDS early warning system in future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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