@InProceedings{CsillikKLFPGOSS:2023:HiAbCa,
               author = "Csillik, Ovidiu and Keller, Michael and Longo, Marcos and Ferraz, 
                         Antonio and Pinag{\'e}, Ekena Rangel and G{\"o}rgens, Eric 
                         Bastos and Ometto, Jean Pierre Henry Balbaud and Silgueiro, 
                         Vinicius and Sattchi, Sassan S.",
          affiliation = "{California Institute of Technology} and {California Institute of 
                         Technology} and {Lawrence Berkeley National Laboratory} and 
                         {California Institute of Technology} and {Oregon State University} 
                         and {Universidade Federal dos Vales do Jequitinhonha e Mucuri} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Centro de Vida (ICV)} and {California Institute of Technology}",
                title = "High-resolution aboveground carbon changes in the Brazilian Amazon 
                         using repeated airborne lidar",
            booktitle = "Proceedings...",
                 year = "2023",
         organization = "AGU FAll Meeting",
            publisher = "AGU",
             abstract = "The Brazilian Amazon is a hotspot of deforestation and forest 
                         degradation caused by logging, fire, and deforestation-associated 
                         fragmentation and edge effects. While the extent of deforestation 
                         and associated carbon losses are relatively well known, the 
                         quantification of the carbon losses caused by degradation and the 
                         carbon gained by recovery of degraded forest ranges widely and is 
                         difficult to quantify accurately regionally. We analyzed forest 
                         changes and associated carbon gains and losses by using repeated 
                         randomized airborne lidar surveys for 2016 and 2017-2018 over 99 
                         different transects, totaling 48,279 ha of forest throughout the 
                         Brazilian Arc of Deforestation. We directly measured changes in 
                         canopy height between the two airborne lidar campaigns, and 
                         gridded the surveyed area into 50 x 50 m cells to estimate 
                         aboveground carbon using a previously calibrated model based on 
                         the top of canopy height. We classified every 0.25 ha cell into 
                         one of the seven forest transition classes: deforestation, forest 
                         fires, logging, windthrows, other disturbances, forest growth, and 
                         no change. We found that disturbances directly attributed to human 
                         activity impacted 4.2% of the survey area while windthrows and 
                         other disturbances affected 2.7% and 14.7% respectively. By 
                         extrapolating the lidar-based statistics to the study area 
                         (544,300 km2), we found that 24.1, 24.2, and 14.5 Tg C y-1 were 
                         lost through deforestation, fires, and logging, respectively. The 
                         losses due to large windthrows (21.5 Tg C y-1) and other 
                         disturbances (50.3 Tg C y-1) were partially counterbalanced by 
                         forest growth (44.1 Tg C y-1). Our high-resolution estimates 
                         demonstrated a greater loss of carbon through forest degradation 
                         than through deforestation and a net loss of carbon of 90.5 ± 20.8 
                         Tg C y-1 for the study region attributable to both anthropogenic 
                         and natural processes. Our regional detailed quantification of 
                         carbon changes highlights that degradation is a major driver of 
                         the carbon budget of the Amazon tropical forest.",
  conference-location = "San Francisco, CA",
      conference-year = "11-15 Dec. 2023",
             language = "en",
        urlaccessdate = "21 maio 2024"
}