title: Carbon emissions from agricultural expansion and intensification in the Chaco.
abstract: Carbon emissions from land-use changes in tropical dry forest systems are poorly understood, although they are likely globally significant. The South American Chaco has recently emerged as a hot spot of agricultural expansion and intensification, as cattle ranching and soybean cultivation expand into forests, and as soybean cultivation replaces grazing lands. Still, our knowledge of the rates and spatial patterns of these land-use changes and how they affected carbon emissions remains partial. We used the Landsat satellite image archive to reconstruct land-use change over the past 30 years and applied a carbon bookkeeping model to quantify how these changes affected carbon budgets. Between 1985 and 2013, more than 142 000 km2of the Chaco's forests, equaling 20% of all forest, was replaced by croplands (38.9%) or grazing lands (61.1%). Of those grazing lands that existed in 1985, about 40% were subsequently converted to cropland. These land-use changes resulted in substantial carbon emissions, totaling 824 Tg C between 1985 and 2013, and 46.2 Tg C for 2013 alone. The majority of these emissions came from forest-to-grazing-land conversions (68%), but post-deforestation land-use change triggered an additional 52.6 Tg C. Although tropical dry forests are less carbon-dense than moist tropical forests, carbon emissions from land-use change in the Chaco were similar in magnitude to those from other major tropical deforestation frontiers. Our study thus highlights the urgent need for an improved monitoring of the often overlooked tropical dry forests and savannas, and more broadly speaking the value of the Landsat image archive for quantifying carbon fluxes from land change.
authors: Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: Matthias
authors: 0000-0003-2375-3622
authors: M
authors: Baumann
authors: CONICET, Instituto de Ecología Regional, Universidad Nacional de Tucumán, CC: 34, CP 4107, Yerba Buena, Tucumán, Argentina.|Integrative Research Institute on Transformations of Human-Environment Systems (IRI THESys), Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: Ignacio
authors: I
authors: Gasparri
authors: Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: María
authors: M
authors: Piquer-Rodríguez
authors: Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Recursos Biológicos (IRB-CNIA), De los Reseros y Las Cabañas S/N HB1712WAA Hurlingham, Buenos Aires, Argentina.
authors: Gregorio
authors: G
authors: Gavier Pizarro
authors: Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: Patrick
authors: P
authors: Griffiths
authors: Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.|Integrative Research Institute on Transformations of Human-Environment Systems (IRI THESys), Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: Patrick
authors: P
authors: Hostert
authors: Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.|Integrative Research Institute on Transformations of Human-Environment Systems (IRI THESys), Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
authors: Tobias
authors: T
authors: Kuemmerle
mesh_terms: D000383:Agriculture; D000818:Animals; D001938:Brazil; D002244:Carbon; D002417:Cattle; D003247:Conservation of Natural Resources; D065928:Forests; D014329:Tropical Climate
chemical_list: D002244:Carbon
keywords: Landsat image archive; carbon bookkeeping model; deforestation frontiers; land-use change; post-deforestation dynamics; savannas; tropical dry forests