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Marques EQ, Silvério DV, Galvão LS, Aragão LEOC, Uribe MR, Macedo MN, Rattis L, Alencar AAC, Brando PM. Assessing the effectiveness of vegetation indices in detecting forest disturbances in the southeast Amazon. Sci Rep 2024; 14:27287. [PMID: 39516263 PMCID: PMC11549415 DOI: 10.1038/s41598-024-77924-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Accepted: 10/28/2024] [Indexed: 11/16/2024] Open
Abstract
Amazon forests are becoming increasingly vulnerable to disturbances such as droughts, fires, windstorms, logging, and forest fragmentation, all of which lead to forest degradation. Nevertheless, quantifying the extent and severity of disturbances and their cumulative impact on forest degradation remains a significant challenge. In this study, we combined multispectral data from Landsat sensors with hyperspectral data from the Earth Observing-One (Hyperion/EO-1) sensor to evaluate the efficacy of multiple vegetation indices in detecting forest responses to disturbances in an experimentally burned forest in southeastern Amazonia. Our experimental area was adjacent to an agricultural field and consisted of three 50-ha treatments - an unburned Control, a plot burned every three years, and a plot burned annually from 2004 to 2010. All plots were monitored to assess vegetation recovery after fire disturbance. These areas were also affected by three drought events (2007, 2010, and 2016) over the study period. We evaluated a total of 18 Vegetation Indices (VI), one unique to Landsat, 12 unique to Hyperion/EO-1, and five commons to both satellites (i.e., 6 total from Landsat and 17 from Hyperion). We used linear models (LM) to evaluate how changes in ground observations of forest structure (biomass, leaf area index [LAI], and litter production) associated with fire were captured by the two VIs most sensitive to forest degradation. Our results indicate that the Plant Senescence Reflectance Index (PSRI) derived from Hyperion/EO-1 was the most sensitive to vegetation changes associated with forest fires, increasing by 94% in burned vs. unburned forests. Of the Landsat-derived VIs, we found that the Green-Red Normalized Difference (GRND) were the most sensitive to forest degradation by fire, showing a marked decline (87%) in the burned plots compared with the unburned Control. However, compared to PSRI, the GRND was a better predictor of changes associated with fire, both in the forest interior or forest edge, for the three ground variables: biomass stocks (r2 = 0.5-0.8), LAI (r2 = 0.8-0.9), and litter production (r2 = 0.4-0.7). This study demonstrate that VIs can detect forest responses to fire and other disturbances over time, highlighting the relative strengths of each VI. In doing so, it shows how the integration of multispectral and hyperspectral data can be useful for monitoring tropical forest degradation and recovery. Moreover, it provides valuable insights into the limitations of existing approaches, which can inform the design of next-generation sensors for global forest monitoring.
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Mataveli G, Jones MW, Carmenta R, Sanchez A, Dutra DJ, Chaves M, de Oliveira G, Anderson LO, Aragão LEOC. Deforestation falls but rise of wildfires continues degrading Brazilian Amazon forests. GLOBAL CHANGE BIOLOGY 2024; 30:e17202. [PMID: 38362838 DOI: 10.1111/gcb.17202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 01/31/2024] [Indexed: 02/17/2024]
Abstract
In 2023, Brazil achieved positive environmental strides in the Amazon, with a 22% reduction in deforestation rates and a 16% decline in total fire counts compared with 2022, attributed to renewed environmental policy implementation. However, despite progress, deforestation remains above the target, and forest wildfires in old‐growth Amazonian forests surged by 152% in 2023 versus 2022, threatening biodiversity and carbon stocks. The rise in fires poses challenges for traditional farmers, impacts urban areas' air quality, and necessitates urgent measures like enhanced firefighting capabilities and long‐term strategies for fire‐free production chains to protect the Amazonian standing forests—a global socio‐environmental asset.
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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, Silva-Junior CHL. Overlooking vegetation loss outside forests imperils the Brazilian Cerrado and other non-forest biomes. Nat Ecol Evol 2024; 8:12-13. [PMID: 37932387 DOI: 10.1038/s41559-023-02256-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
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Heinrich V, House J, Gibbs DA, Harris N, Herold M, Grassi G, Cantinho R, Rosan TM, Zimbres B, Shimbo JZ, Melo J, Hales T, Sitch S, Aragão LEOC. Mind the gap: reconciling tropical forest carbon flux estimates from earth observation and national reporting requires transparency. CARBON BALANCE AND MANAGEMENT 2023; 18:22. [PMID: 37982938 PMCID: PMC10662451 DOI: 10.1186/s13021-023-00240-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 10/18/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND The application of different approaches calculating the anthropogenic carbon net flux from land, leads to estimates that vary considerably. One reason for these variations is the extent to which approaches consider forest land to be "managed" by humans, and thus contributing to the net anthropogenic flux. Global Earth Observation (EO) datasets characterising spatio-temporal changes in land cover and carbon stocks provide an independent and consistent approach to estimate forest carbon fluxes. These can be compared against results reported in National Greenhouse Gas Inventories (NGHGIs) to support accurate and timely measuring, reporting and verification (MRV). Using Brazil as a primary case study, with additional analysis in Indonesia and Malaysia, we compare a Global EO-based dataset of forest carbon fluxes to results reported in NGHGIs. RESULTS Between 2001 and 2020, the EO-derived estimates of all forest-related emissions and removals indicate that Brazil was a net sink of carbon (- 0.2 GtCO2yr-1), while Brazil's NGHGI reported a net carbon source (+ 0.8 GtCO2yr-1). After adjusting the EO estimate to use the Brazilian NGHGI definition of managed forest and other assumptions used in the inventory's methodology, the EO net flux became a source of + 0.6 GtCO2yr-1, comparable to the NGHGI. Remaining discrepancies are due largely to differing carbon removal factors and forest types applied in the two datasets. In Indonesia, the EO and NGHGI net flux estimates were similar (+ 0.6 GtCO2 yr-1), but in Malaysia, they differed in both magnitude and sign (NGHGI: -0.2 GtCO2 yr-1; Global EO: + 0.2 GtCO2 yr-1). Spatially explicit datasets on forest types were not publicly available for analysis from either NGHGI, limiting the possibility of detailed adjustments. CONCLUSIONS By adjusting the EO dataset to improve comparability with carbon fluxes estimated for managed forests in the Brazilian NGHGI, initially diverging estimates were largely reconciled and remaining differences can be explained. Despite limited spatial data available for Indonesia and Malaysia, our comparison indicated specific aspects where differing approaches may explain divergence, including uncertainties and inaccuracies. Our study highlights the importance of enhanced transparency, as set out by the Paris Agreement, to enable alignment between different approaches for independent measuring and verification.
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Peripato V, Levis C, Moreira GA, Gamerman D, Ter Steege H, Pitman NCA, de Souza JG, Iriarte J, Robinson M, Junqueira AB, Trindade TB, de Almeida FO, Moraes CDP, Lombardo U, Tamanaha EK, Maezumi SY, Ometto JPHB, Braga JRG, Campanharo WA, Cassol HLG, Leal PR, de Assis MLR, da Silva AM, Phillips OL, Costa FRC, Flores BM, Hoffman B, Henkel TW, Umaña MN, Magnusson WE, Valderrama Sandoval EH, Barlow J, Milliken W, Lopes MA, Simon MF, van Andel TR, Laurance SGW, Laurance WF, Torres-Lezama A, Assis RL, Molino JF, Mestre M, Hamblin M, Coelho LDS, Lima Filho DDA, Wittmann F, Salomão RP, Amaral IL, Guevara JE, de Almeida Matos FD, Castilho CV, Carim MDJV, Cárdenas López D, Sabatier D, Irume MV, Martins MP, Guimarães JRDS, Bánki OS, Piedade MTF, Ramos JF, Luize BG, Novo EMMDL, Núñez Vargas P, Silva TSF, Venticinque EM, Manzatto AG, Reis NFC, Terborgh J, Casula KR, Demarchi LO, Honorio Coronado EN, Monteagudo Mendoza A, Montero JC, Schöngart J, Feldpausch TR, Quaresma AC, Aymard C GA, Baraloto C, Castaño Arboleda N, Engel J, Petronelli P, Zartman CE, Killeen TJ, Marimon BS, Marimon-Junior BH, Schietti J, Sousa TR, Vasquez R, Rincón LM, Berenguer E, Ferreira J, Mostacedo B, do Amaral DD, Castellanos H, de Medeiros MB, Andrade A, Camargo JL, Farias EDS, Magalhães JLL, Mendonça Nascimento HE, de Queiroz HL, Brienen R, Cardenas Revilla JD, Stevenson PR, Araujo-Murakami A, Barçante Ladvocat Cintra B, Feitosa YO, Barbosa FR, Carpanedo RDS, Duivenvoorden JF, de Noronha JDC, Rodrigues DDJ, Mogollón HF, Ferreira LV, Householder JE, Lozada JR, Comiskey JA, Draper FC, de Toledo JJ, Damasco G, Dávila N, García-Villacorta R, Lopes A, Cornejo Valverde F, Alonso A, Dallmeier F, Gomes VHF, Jimenez EM, Neill D, Peñuela Mora MC, de Aguiar DPP, Arroyo L, Antunes Carvalho F, Coelho de Souza F, Feeley KJ, Gribel R, Pansonato MP, Ríos Paredes M, Brasil da Silva I, Ferreira MJ, Fine PVA, Fonty É, Guedes MC, Licona JC, Pennington T, Peres CA, Villa Zegarra BE, Parada GA, Pardo Molina G, Vos VA, Cerón C, Maas P, Silveira M, Stropp J, Thomas R, Baker TR, Daly D, Huamantupa-Chuquimaco I, Vieira ICG, Weiss Albuquerque B, Fuentes A, Klitgaard B, Marcelo-Peña JL, Silman MR, Tello JS, Vriesendorp C, Chave J, Di Fiore A, Hilário RR, Phillips JF, Rivas-Torres G, von Hildebrand P, Pereira LDO, Barbosa EM, de Matos Bonates LC, Doza HPD, Zárate Gómez R, Gallardo Gonzales GP, Gonzales T, Malhi Y, de Andrade Miranda IP, Mozombite Pinto LF, Prieto A, Rudas A, Ruschel AR, Silva N, Vela CIA, Zent EL, Zent S, Cano A, Carrero Márquez YA, Correa DF, Costa JBP, Galbraith D, Holmgren M, Kalamandeen M, Lobo G, Nascimento MT, Oliveira AA, Ramirez-Angulo H, Rocha M, Scudeller VV, Sierra R, Tirado M, van der Heijden G, Vilanova Torre E, Ahuite Reategui MA, Baider C, Balslev H, Cárdenas S, Casas LF, Farfan-Rios W, Ferreira C, Linares-Palomino R, Mendoza C, Mesones I, Urrego Giraldo LE, Villarroel D, Zagt R, Alexiades MN, de Oliveira EA, Garcia-Cabrera K, Hernandez L, Palacios Cuenca W, Pansini S, Pauletto D, Ramirez Arevalo F, Sampaio AF, Valenzuela Gamarra L, Aragão LEOC. More than 10,000 pre-Columbian earthworks are still hidden throughout Amazonia. Science 2023; 382:103-109. [PMID: 37797008 DOI: 10.1126/science.ade2541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 08/31/2023] [Indexed: 10/07/2023]
Abstract
Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest. We also identified 53 domesticated tree species significantly associated with earthwork occurrence probability, likely suggesting past management practices. Closed-canopy forests across Amazonia are likely to contain thousands of undiscovered archaeological sites around which pre-Columbian societies actively modified forests, a discovery that opens opportunities for better understanding the magnitude of ancient human influence on Amazonia and its current state.
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Gatti LV, Cunha CL, Marani L, Cassol HLG, Messias CG, Arai E, Denning AS, Soler LS, Almeida C, Setzer A, Domingues LG, Basso LS, Miller JB, Gloor M, Correia CSC, Tejada G, Neves RAL, Rajao R, Nunes F, Filho BSS, Schmitt J, Nobre C, Corrêa SM, Sanches AH, Aragão LEOC, Anderson L, Von Randow C, Crispim SP, Silva FM, Machado GBM. Increased Amazon carbon emissions mainly from decline in law enforcement. Nature 2023; 621:318-323. [PMID: 37612502 DOI: 10.1038/s41586-023-06390-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 06/30/2023] [Indexed: 08/25/2023]
Abstract
The Amazon forest carbon sink is declining, mainly as a result of land-use and climate change1-4. Here we investigate how changes in law enforcement of environmental protection policies may have affected the Amazonian carbon balance between 2010 and 2018 compared with 2019 and 2020, based on atmospheric CO2 vertical profiles5,6, deforestation7 and fire data8, as well as infraction notices related to illegal deforestation9. We estimate that Amazonia carbon emissions increased from a mean of 0.24 ± 0.08 PgC year-1 in 2010-2018 to 0.44 ± 0.10 PgC year-1 in 2019 and 0.52 ± 0.10 PgC year-1 in 2020 (± uncertainty). The observed increases in deforestation were 82% and 77% (94% accuracy) and burned area were 14% and 42% in 2019 and 2020 compared with the 2010-2018 mean, respectively. We find that the numbers of notifications of infractions against flora decreased by 30% and 54% and fines paid by 74% and 89% in 2019 and 2020, respectively. Carbon losses during 2019-2020 were comparable with those of the record warm El Niño (2015-2016) without an extreme drought event. Statistical tests show that the observed differences between the 2010-2018 mean and 2019-2020 are unlikely to have arisen by chance. The changes in the carbon budget of Amazonia during 2019-2020 were mainly because of western Amazonia becoming a carbon source. Our results indicate that a decline in law enforcement led to increases in deforestation, biomass burning and forest degradation, which increased carbon emissions and enhanced drying and warming of the Amazon forests.
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Ferreira IJM, Campanharo WA, Fonseca MG, Escada MIS, Nascimento MT, Villela DM, Brancalion P, Magnago LFS, Anderson LO, Nagy L, Aragão LEOC. Potential aboveground biomass increase in Brazilian Atlantic Forest fragments with climate change. GLOBAL CHANGE BIOLOGY 2023; 29:3098-3113. [PMID: 36883779 DOI: 10.1111/gcb.16670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 02/03/2023] [Indexed: 05/03/2023]
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.
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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, Melo M. Brazilian Amazon indigenous territories under deforestation pressure. Sci Rep 2023; 13:5851. [PMID: 37037850 PMCID: PMC10085996 DOI: 10.1038/s41598-023-32746-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 03/31/2023] [Indexed: 04/12/2023] Open
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 (CO2) 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.
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Heinrich VHA, Vancutsem C, Dalagnol R, Rosan TM, Fawcett D, Silva-Junior CHL, Cassol HLG, Achard F, Jucker T, Silva CA, House J, Sitch S, Hales TC, Aragão LEOC. The carbon sink of secondary and degraded humid tropical forests. Nature 2023; 615:436-442. [PMID: 36922608 DOI: 10.1038/s41586-022-05679-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 12/16/2022] [Indexed: 03/17/2023]
Abstract
The globally important carbon sink of intact, old-growth tropical humid forests is declining because of climate change, deforestation and degradation from fire and logging1-3. Recovering tropical secondary and degraded forests now cover about 10% of the tropical forest area4, but how much carbon they accumulate remains uncertain. Here we quantify the aboveground carbon (AGC) sink of recovering forests across three main continuous tropical humid regions: the Amazon, Borneo and Central Africa5,6. On the basis of satellite data products4,7, our analysis encompasses the heterogeneous spatial and temporal patterns of growth in degraded and secondary forests, influenced by key environmental and anthropogenic drivers. In the first 20 years of recovery, regrowth rates in Borneo were up to 45% and 58% higher than in Central Africa and the Amazon, respectively. This is due to variables such as temperature, water deficit and disturbance regimes. We find that regrowing degraded and secondary forests accumulated 107 Tg C year-1 (90-130 Tg C year-1) between 1984 and 2018, counterbalancing 26% (21-34%) of carbon emissions from humid tropical forest loss during the same period. Protecting old-growth forests is therefore a priority. Furthermore, we estimate that conserving recovering degraded and secondary forests can have a feasible future carbon sink potential of 53 Tg C year-1 (44-62 Tg C year-1) across the main tropical regions studied.
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Fawcett D, Sitch S, Ciais P, Wigneron JP, Silva‐Junior CHL, Heinrich V, Vancutsem C, Achard F, Bastos A, Yang H, Li X, Albergel C, Friedlingstein P, Aragão LEOC. Declining Amazon biomass due to deforestation and subsequent degradation losses exceeding gains. GLOBAL CHANGE BIOLOGY 2023; 29:1106-1118. [PMID: 36415966 PMCID: PMC10100003 DOI: 10.1111/gcb.16513] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
In the Amazon, deforestation and climate change lead to increased vulnerability to forest degradation, threatening its existing carbon stocks and its capacity as a carbon sink. We use satellite L-Band Vegetation Optical Depth (L-VOD) data that provide an integrated (top-down) estimate of biomass carbon to track changes over 2011-2019. Because the spatial resolution of L-VOD is coarse (0.25°), it allows limited attribution of the observed changes. We therefore combined high-resolution annual maps of forest cover and disturbances with biomass maps to model carbon losses (bottom-up) from deforestation and degradation, and gains from regrowing secondary forests. We show an increase of deforestation and associated degradation losses since 2012 which greatly outweigh secondary forest gains. Degradation accounted for 40% of gross losses. After an increase in 2011, old-growth forests show a net loss of above-ground carbon between 2012 and 2019. The sum of component carbon fluxes in our model is consistent with the total biomass change from L-VOD of 1.3 Pg C over 2012-2019. Across nine Amazon countries, we found that while Brazil contains the majority of biomass stocks (64%), its losses from disturbances were disproportionately high (79% of gross losses). Our multi-source analysis provides a pessimistic assessment of the Amazon carbon balance and highlights the urgent need to stop the recent rise of deforestation and degradation, particularly in the Brazilian Amazon.
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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, Walker WS. The drivers and impacts of Amazon forest degradation. Science 2023; 379:eabp8622. [PMID: 36701452 DOI: 10.1126/science.abp8622] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Approximately 2.5 × 106 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.
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Mataveli G, de Oliveira G, Silva-Junior CHL, Stark SC, Carvalho N, Anderson LO, Gatti LV, Aragão LEOC. Record-breaking fires in the Brazilian Amazon associated with uncontrolled deforestation. Nat Ecol Evol 2022; 6:1792-1793. [PMID: 36396971 DOI: 10.1038/s41559-022-01945-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Bastos A, Ciais P, Sitch S, Aragão LEOC, Chevallier F, Fawcett D, Rosan TM, Saunois M, Günther D, Perugini L, Robert C, Deng Z, Pongratz J, Ganzenmüller R, Fuchs R, Winkler K, Zaehle S, Albergel C. On the use of Earth Observation to support estimates of national greenhouse gas emissions and sinks for the Global stocktake process: lessons learned from ESA-CCI RECCAP2. CARBON BALANCE AND MANAGEMENT 2022; 17:15. [PMID: 36183029 PMCID: PMC9526973 DOI: 10.1186/s13021-022-00214-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 09/04/2022] [Indexed: 06/16/2023]
Abstract
The Global Stocktake (GST), implemented by the Paris Agreement, requires rapid developments in the capabilities to quantify annual greenhouse gas (GHG) emissions and removals consistently from the global to the national scale and improvements to national GHG inventories. In particular, new capabilities are needed for accurate attribution of sources and sinks and their trends to natural and anthropogenic processes. On the one hand, this is still a major challenge as national GHG inventories follow globally harmonized methodologies based on the guidelines established by the Intergovernmental Panel on Climate Change, but these can be implemented differently for individual countries. Moreover, in many countries the capability to systematically produce detailed and annually updated GHG inventories is still lacking. On the other hand, spatially-explicit datasets quantifying sources and sinks of carbon dioxide, methane and nitrous oxide emissions from Earth Observations (EO) are still limited by many sources of uncertainty. While national GHG inventories follow diverse methodologies depending on the availability of activity data in the different countries, the proposed comparison with EO-based estimates can help improve our understanding of the comparability of the estimates published by the different countries. Indeed, EO networks and satellite platforms have seen a massive expansion in the past decade, now covering a wide range of essential climate variables and offering high potential to improve the quantification of global and regional GHG budgets and advance process understanding. Yet, there is no EO data that quantifies greenhouse gas fluxes directly, rather there are observations of variables or proxies that can be transformed into fluxes using models. Here, we report results and lessons from the ESA-CCI RECCAP2 project, whose goal was to engage with National Inventory Agencies to improve understanding about the methods used by each community to estimate sources and sinks of GHGs and to evaluate the potential for satellite and in-situ EO to improve national GHG estimates. Based on this dialogue and recent studies, we discuss the potential of EO approaches to provide estimates of GHG budgets that can be compared with those of national GHG inventories. We outline a roadmap for implementation of an EO carbon-monitoring program that can contribute to the Paris Agreement.
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Cunha HFV, Andersen KM, Lugli LF, Santana FD, Aleixo IF, Moraes AM, Garcia S, Di Ponzio R, Mendoza EO, Brum B, Rosa JS, Cordeiro AL, Portela BTT, Ribeiro G, Coelho SD, de Souza ST, Silva LS, Antonieto F, Pires M, Salomão AC, Miron AC, de Assis RL, Domingues TF, Aragão LEOC, Meir P, Camargo JL, Manzi AO, Nagy L, Mercado LM, Hartley IP, Quesada CA. Direct evidence for phosphorus limitation on Amazon forest productivity. Nature 2022; 608:558-562. [PMID: 35948632 DOI: 10.1038/s41586-022-05085-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 07/07/2022] [Indexed: 11/09/2022]
Abstract
The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.
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Mataveli G, de Oliveira G, Chaves MED, Dalagnol R, Wagner FH, Ipia AHS, Silva‐Junior CHL, Aragão LEOC. Science‐based planning can support law enforcement actions to curb deforestation in the Brazilian Amazon. Conserv Lett 2022. [DOI: 10.1111/conl.12908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Berenguer E, Lennox GD, Ferreira J, Malhi Y, Aragão LEOC, Barreto JR, Del Bon Espírito-Santo F, Figueiredo AES, França F, Gardner TA, Joly CA, Palmeira AF, Quesada CA, Rossi LC, de Seixas MMM, Smith CC, Withey K, Barlow J. Tracking the impacts of El Niño drought and fire in human-modified Amazonian forests. Proc Natl Acad Sci U S A 2021; 118:e2019377118. [PMID: 34282005 PMCID: PMC8325159 DOI: 10.1073/pnas.2019377118] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
With humanity facing an unprecedented climate crisis, the conservation of tropical forests has never been so important - their vast terrestrial carbon stocks can be turned into emissions by climatic and human disturbances. However, the duration of these effects is poorly understood, and it is unclear whether impacts are amplified in forests with a history of previous human disturbance. Here, we focus on the Amazonian epicenter of the 2015-16 El Niño, a region that encompasses 1.2% of the Brazilian Amazon. We quantify, at high temporal resolution, the impacts of an extreme El Niño (EN) drought and extensive forest fires on plant mortality and carbon loss in undisturbed and human-modified forests. Mortality remained higher than pre-El Niño levels for 36 mo in EN-drought-affected forests and for 30 mo in EN-fire-affected forests. In EN-fire-affected forests, human disturbance significantly increased plant mortality. Our investigation of the ecological and physiological predictors of tree mortality showed that trees with lower wood density, bark thickness and leaf nitrogen content, as well as those that experienced greater fire intensity, were more vulnerable. Across the region, the 2015-16 El Niño led to the death of an estimated 2.5 ± 0.3 billion stems, resulting in emissions of 495 ± 94 Tg CO2 Three years after the El Niño, plant growth and recruitment had offset only 37% of emissions. Our results show that limiting forest disturbance will not only help maintain carbon stocks, but will also maximize the resistance of Amazonian forests if fires do occur.
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Pletsch MAJS, Silva Junior CHL, Penha TV, Körting TS, Silva MES, Pereira G, Anderson LO, Aragão LEOC. The 2020 Brazilian Pantanal fires. AN ACAD BRAS CIENC 2021; 93:e20210077. [PMID: 34161516 DOI: 10.1590/0001-3765202120210077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 02/02/2021] [Indexed: 11/21/2022] Open
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Draper FC, Costa FRC, Arellano G, Phillips OL, Duque A, Macía MJ, Ter Steege H, Asner GP, Berenguer E, Schietti J, Socolar JB, de Souza FC, Dexter KG, Jørgensen PM, Tello JS, Magnusson WE, Baker TR, Castilho CV, Monteagudo-Mendoza A, Fine PVA, Ruokolainen K, Coronado ENH, Aymard G, Dávila N, Sáenz MS, Paredes MAR, Engel J, Fortunel C, Paine CET, Goret JY, Dourdain A, Petronelli P, Allie E, Andino JEG, Brienen RJW, Pérez LC, Manzatto ÂG, Zambrana NYP, Molino JF, Sabatier D, Chave J, Fauset S, Villacorta RG, Réjou-Méchain M, Berry PE, Melgaço K, Feldpausch TR, Sandoval EV, Martinez RV, Mesones I, Junqueira AB, Roucoux KH, de Toledo JJ, Andrade AC, Camargo JL, Del Aguila Pasquel J, Santana FD, Laurance WF, Laurance SG, Lovejoy TE, Comiskey JA, Galbraith DR, Kalamandeen M, Aguilar GEN, Arenas JV, Guerra CAA, Flores M, Llampazo GF, Montenegro LAT, Gomez RZ, Pansonato MP, Moscoso VC, Vleminckx J, Barrantes OJV, Duivenvoorden JF, de Sousa SA, Arroyo L, Perdiz RO, Cravo JS, Marimon BS, Junior BHM, Carvalho FA, Damasco G, Disney M, Vital MS, Diaz PRS, Vicentini A, Nascimento H, Higuchi N, Van Andel T, Malhi Y, Ribeiro SC, Terborgh JW, Thomas RS, Dallmeier F, Prieto A, Hilário RR, Salomão RP, Silva RDC, Casas LF, Vieira ICG, Araujo-Murakami A, Arevalo FR, Ramírez-Angulo H, Torre EV, Peñuela MC, Killeen TJ, Pardo G, Jimenez-Rojas E, Castro W, Cabrera DG, Pipoly J, de Sousa TR, Silvera M, Vos V, Neill D, Vargas PN, Vela DM, Aragão LEOC, Umetsu RK, Sierra R, Wang O, Young KR, Prestes NCCS, Massi KG, Huaymacari JR, Gutierrez GAP, Aldana AM, Alexiades MN, Baccaro F, Céron C, Muelbert AE, Rios JMG, Lima AS, Lloyd JL, Pitman NCA, Gamarra LV, Oroche CJC, Fuentes AF, Palacios W, Patiño S, Torres-Lezama A, Baraloto C. Amazon tree dominance across forest strata. Nat Ecol Evol 2021; 5:757-767. [PMID: 33795854 DOI: 10.1038/s41559-021-01418-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 02/18/2021] [Indexed: 02/01/2023]
Abstract
The forests of Amazonia are among the most biodiverse plant communities on Earth. Given the immediate threats posed by climate and land-use change, an improved understanding of how this extraordinary biodiversity is spatially organized is urgently required to develop effective conservation strategies. Most Amazonian tree species are extremely rare but a few are common across the region. Indeed, just 227 'hyperdominant' species account for >50% of all individuals >10 cm diameter at 1.3 m in height. Yet, the degree to which the phenomenon of hyperdominance is sensitive to tree size, the extent to which the composition of dominant species changes with size class and how evolutionary history constrains tree hyperdominance, all remain unknown. Here, we use a large floristic dataset to show that, while hyperdominance is a universal phenomenon across forest strata, different species dominate the forest understory, midstory and canopy. We further find that, although species belonging to a range of phylogenetically dispersed lineages have become hyperdominant in small size classes, hyperdominants in large size classes are restricted to a few lineages. Our results demonstrate that it is essential to consider all forest strata to understand regional patterns of dominance and composition in Amazonia. More generally, through the lens of 654 hyperdominant species, we outline a tractable pathway for understanding the functioning of half of Amazonian forests across vertical strata and geographical locations.
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Pontes-Lopes A, Silva CVJ, Barlow J, Rincón LM, Campanharo WA, Nunes CA, de Almeida CT, Silva Júnior CHL, Cassol HLG, Dalagnol R, Stark SC, Graça PMLA, Aragão LEOC. Drought-driven wildfire impacts on structure and dynamics in a wet Central Amazonian forest. Proc Biol Sci 2021; 288:20210094. [PMID: 34004131 PMCID: PMC8131120 DOI: 10.1098/rspb.2021.0094] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/23/2021] [Indexed: 11/12/2022] Open
Abstract
While the climate and human-induced forest degradation is increasing in the Amazon, fire impacts on forest dynamics remain understudied in the wetter regions of the basin, which are susceptible to large wildfires only during extreme droughts. To address this gap, we installed burned and unburned plots immediately after a wildfire in the northern Purus-Madeira (Central Amazon) during the 2015 El-Niño. We measured all individuals with diameter of 10 cm or more at breast height and conducted recensuses to track the demographic drivers of biomass change over 3 years. We also assessed how stem-level growth and mortality were influenced by fire intensity (proxied by char height) and tree morphological traits (size and wood density). Overall, the burned forest lost 27.3% of stem density and 12.8% of biomass, concentrated in small and medium trees. Mortality drove these losses in the first 2 years and recruitment decreased in the third year. The fire increased growth in lower wood density and larger sized trees, while char height had transitory strong effects increasing tree mortality. Our findings suggest that fire impacts are weaker in the wetter Amazon. Here, trees of greater sizes and higher wood densities may confer a margin of fire resistance; however, this may not extend to higher intensity fires arising from climate change.
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Lugli LF, Rosa JS, Andersen KM, Di Ponzio R, Almeida RV, Pires M, Cordeiro AL, Cunha HFV, Martins NP, Assis RL, Moraes ACM, Souza ST, Aragão LEOC, Camargo JL, Fuchslueger L, Schaap KJ, Valverde-Barrantes OJ, Meir P, Quesada CA, Mercado LM, Hartley IP. Rapid responses of root traits and productivity to phosphorus and cation additions in a tropical lowland forest in Amazonia. THE NEW PHYTOLOGIST 2021; 230:116-128. [PMID: 33341935 DOI: 10.1111/nph.17154] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Soil nutrient availability can strongly affect root traits. In tropical forests, phosphorus (P) is often considered the main limiting nutrient for plants. However, support for the P paradigm is limited, and N and cations might also control tropical forests functioning. We used a large-scale experiment to determine how the factorial addition of nitrogen (N), P and cations affected root productivity and traits related to nutrient acquisition strategies (morphological traits, phosphatase activity, arbuscular mycorrhizal colonisation and nutrient contents) in a primary rainforest growing on low-fertility soils in Central Amazonia after 1 yr of fertilisation. Multiple root traits and productivity were affected. Phosphorus additions increased annual root productivity and root diameter, but decreased root phosphatase activity. Cation additions increased root productivity at certain times of year, also increasing root diameter and mycorrhizal colonisation. P and cation additions increased their element concentrations in root tissues. No responses were detected with N addition. Here we showed that rock-derived nutrients determined root functioning in low-fertility Amazonian soils, demonstrating not only the hypothesised importance of P, but also highlighting the role of cations. The changes in fine root traits and productivity indicated that even slow-growing tropical rainforests can respond rapidly to changes in resource availability.
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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, Aragão LEOC. Large carbon sink potential of secondary forests in the Brazilian Amazon to mitigate climate change. Nat Commun 2021; 12:1785. [PMID: 33741981 PMCID: PMC7979697 DOI: 10.1038/s41467-021-22050-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 02/19/2021] [Indexed: 01/31/2023] Open
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.
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Vancutsem C, Achard F, Pekel JF, Vieilledent G, Carboni S, Simonetti D, Gallego J, Aragão LEOC, Nasi R. Long-term (1990-2019) monitoring of forest cover changes in the humid tropics. SCIENCE ADVANCES 2021; 7:7/10/eabe1603. [PMID: 33674308 PMCID: PMC7935368 DOI: 10.1126/sciadv.abe1603] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 01/21/2021] [Indexed: 05/22/2023]
Abstract
Accurate characterization of tropical moist forest changes is needed to support conservation policies and to quantify their contribution to global carbon fluxes more effectively. We document, at pantropical scale, the extent and changes (degradation, deforestation, and recovery) of these forests over the past three decades. We estimate that 17% of tropical moist forests have disappeared since 1990 with a remaining area of 1071 million hectares in 2019, from which 10% are degraded. Our study underlines the importance of the degradation process in these ecosystems, in particular, as a precursor of deforestation, and in the recent increase in tropical moist forest disturbances (natural and anthropogenic degradation or deforestation). Without a reduction of the present disturbance rates, undisturbed forests will disappear entirely in large tropical humid regions by 2050. Our study suggests that reinforcing actions are needed to prevent the initial degradation that leads to forest clearance in 45% of the cases.
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Ziccardi LG, dos Reis M, Graça PMLDA, Gonçalves NB, Pontes‐Lopes A, Aragão LEOC, de Oliveira RP, Clark L, Fearnside PM. Forest fires facilitate growth of herbaceous bamboos in central Amazonia. Biotropica 2021. [DOI: 10.1111/btp.12915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Berenguer E, Carvalho N, Anderson LO, Aragão LEOC, França F, Barlow J. Improving the spatial-temporal analysis of Amazonian fires. GLOBAL CHANGE BIOLOGY 2021; 27:469-471. [PMID: 33124173 DOI: 10.1111/gcb.15425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 10/23/2020] [Indexed: 06/11/2023]
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.
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Dalagnol R, Wagner FH, Galvão LS, Streher AS, Phillips OL, Gloor E, Pugh TAM, Ometto JPHB, Aragão LEOC. Large-scale variations in the dynamics of Amazon forest canopy gaps from airborne lidar data and opportunities for tree mortality estimates. Sci Rep 2021; 11:1388. [PMID: 33446809 PMCID: PMC7809196 DOI: 10.1038/s41598-020-80809-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/28/2020] [Indexed: 01/27/2023] Open
Abstract
We report large-scale estimates of Amazonian gap dynamics using a novel approach with large datasets of airborne light detection and ranging (lidar), including five multi-temporal and 610 single-date lidar datasets. Specifically, we (1) compared the fixed height and relative height methods for gap delineation and established a relationship between static and dynamic gaps (newly created gaps); (2) explored potential environmental/climate drivers explaining gap occurrence using generalized linear models; and (3) cross-related our findings to mortality estimates from 181 field plots. Our findings suggest that static gaps are significantly correlated to dynamic gaps and can inform about structural changes in the forest canopy. Moreover, the relative height outperformed the fixed height method for gap delineation. Well-defined and consistent spatial patterns of dynamic gaps were found over the Amazon, while also revealing the dynamics of areas never sampled in the field. The predominant pattern indicates 20-35% higher gap dynamics at the west and southeast than at the central-east and north. These estimates were notably consistent with field mortality patterns, but they showed 60% lower magnitude likely due to the predominant detection of the broken/uprooted mode of death. While topographic predictors did not explain gap occurrence, the water deficit, soil fertility, forest flooding and degradation were key drivers of gap variability at the regional scale. These findings highlight the importance of lidar in providing opportunities for large-scale gap dynamics and tree mortality monitoring over the Amazon.
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