35
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Size and frequency of natural forest disturbances and the Amazon forest carbon balance

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Forest inventory studies in the Amazon indicate a large terrestrial carbon sink. However, field plots may fail to represent forest mortality processes at landscape-scales of tropical forests. Here we characterize the frequency distribution of disturbance events in natural forests from 0.01 ha to 2,651 ha size throughout Amazonia using a novel combination of forest inventory, airborne lidar and satellite remote sensing data. We find that small-scale mortality events are responsible for aboveground biomass losses of ~1.7 Pg C y −1 over the entire Amazon region. We also find that intermediate-scale disturbances account for losses of ~0.2 Pg C y −1, and that the largest-scale disturbances as a result of blow-downs only account for losses of ~0.004 Pg C y −1. Simulation of growth and mortality indicates that even when all carbon losses from intermediate and large-scale disturbances are considered, these are outweighed by the net biomass accumulation by tree growth, supporting the inference of an Amazon carbon sink.

          Abstract

          The world’s tropical forests represent a terrestrial carbon sink, yet its size is uncertain. Espírito-Santo et al. characterize full Amazon disturbances combining forest inventories and remote sensing data, and use statistical modelling to quantify the Amazon aboveground forest carbon balance.

          Related collections

          Most cited references 29

          • Record: found
          • Abstract: not found
          • Book: not found

          Spatial Statistics

           Brian Ripley (1981)
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems.

            Knowledge of carbon exchange between the atmosphere, land and the oceans is important, given that the terrestrial and marine environments are currently absorbing about half of the carbon dioxide that is emitted by fossil-fuel combustion. This carbon uptake is therefore limiting the extent of atmospheric and climatic change, but its long-term nature remains uncertain. Here we provide an overview of the current state of knowledge of global and regional patterns of carbon exchange by terrestrial ecosystems. Atmospheric carbon dioxide and oxygen data confirm that the terrestrial biosphere was largely neutral with respect to net carbon exchange during the 1980s, but became a net carbon sink in the 1990s. This recent sink can be largely attributed to northern extratropical areas, and is roughly split between North America and Eurasia. Tropical land areas, however, were approximately in balance with respect to carbon exchange, implying a carbon sink that offset emissions due to tropical deforestation. The evolution of the terrestrial carbon sink is largely the result of changes in land use over time, such as regrowth on abandoned agricultural land and fire prevention, in addition to responses to environmental changes, such as longer growing seasons, and fertilization by carbon dioxide and nitrogen. Nevertheless, there remain considerable uncertainties as to the magnitude of the sink in different regions and the contribution of different processes.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Increasing carbon storage in intact African tropical forests.

              The response of terrestrial vegetation to a globally changing environment is central to predictions of future levels of atmospheric carbon dioxide. The role of tropical forests is critical because they are carbon-dense and highly productive. Inventory plots across Amazonia show that old-growth forests have increased in carbon storage over recent decades, but the response of one-third of the world's tropical forests in Africa is largely unknown owing to an absence of spatially extensive observation networks. Here we report data from a ten-country network of long-term monitoring plots in African tropical forests. We find that across 79 plots (163 ha) above-ground carbon storage in live trees increased by 0.63 Mg C ha(-1) yr(-1) between 1968 and 2007 (95% confidence interval (CI), 0.22-0.94; mean interval, 1987-96). Extrapolation to unmeasured forest components (live roots, small trees, necromass) and scaling to the continent implies a total increase in carbon storage in African tropical forest trees of 0.34 Pg C yr(-1) (CI, 0.15-0.43). These reported changes in carbon storage are similar to those reported for Amazonian forests per unit area, providing evidence that increasing carbon storage in old-growth forests is a pan-tropical phenomenon. Indeed, combining all standardized inventory data from this study and from tropical America and Asia together yields a comparable figure of 0.49 Mg C ha(-1) yr(-1) (n = 156; 562 ha; CI, 0.29-0.66; mean interval, 1987-97). This indicates a carbon sink of 1.3 Pg C yr(-1) (CI, 0.8-1.6) across all tropical forests during recent decades. Taxon-specific analyses of African inventory and other data suggest that widespread changes in resource availability, such as increasing atmospheric carbon dioxide concentrations, may be the cause of the increase in carbon stocks, as some theory and models predict.
                Bookmark

                Author and article information

                Journal
                Nat Commun
                Nat Commun
                Nature Communications
                Nature Pub. Group
                2041-1723
                18 March 2014
                : 5
                Affiliations
                [1 ]NASA Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California 91109, USA
                [2 ]Institute for the Study of Earth, Oceans and Space, University of New Hampshire , Durham, New Hampshire 03824, USA
                [3 ]School of Geography, University of Leeds , Leeds LS2 9JT, UK
                [4 ]USDA Forest Service, International Institute of Tropical Forestry , San Juan 00926-1119, Puerto Rico
                [5 ]EMBRAPA Monitoramento por Satélite , Campinas, Sao Paulo CEP 13070-115, Brazil
                [6 ]Environmental Change Institute, School of Geography and the Environment, University of Oxford , Oxford OX1 3QY, UK
                [7 ]National Institute for Research in Amazonia (INPA), CP 478 , Manaus, Amazonas 69011-970, Brazil
                [8 ]EMBRAPA Amazônia Oriental (CPATU) , Santarém, Pará CEP 68035-110 C.P. 261, Brazil
                [9 ]Belterra, Pará CEP 68143-000, Brazil
                [10 ]Centre for Tropical Environmental and Sustainability Science (TESS), School of Earth and Environmental Sciences, James Cook University , Cairns, Queensland 4878, Australia
                [11 ]National Institute for Space Research (INPE) , São José dos Campos, Sao Paulo CEP 12227-010, Brazil
                [12 ]Jardin Botanico de Missouri , Oxapampa 19231, Pasco, Peru
                [13 ]Department of Global Ecology, Carnegie Institution for Science , Stanford, California 94305, USA
                [14 ]School of Geography, University of Nottingham, University Park , Nottingham NG7 2RD, UK
                [15 ]Present address: College of Life and Environmental Sciences, University of Exeter, Rennes Drive, Exeter EX4 4RJ, UK
                Author notes
                Article
                ncomms4434
                10.1038/ncomms4434
                4273466
                24643258
                4d60a25b-5dbb-43d9-892a-2ef28601bc03
                Copyright © 2014, Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.

                This work is licensed under a Creative Commons Attribution 3.0 Unported License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/3.0/

                Categories
                Article

                Uncategorized

                Comments

                Comment on this article