INCITAP   20787
INSTITUTO DE CIENCIAS DE LA TIERRA Y AMBIENTALES DE LA PAMPA
Unidad Ejecutora - UE
artículos
Título:
Reassessing the role of grazing lands in carbon-balance estimations: Meta-analysis and review
Autor/es:
TABOADA, M.A.; RICARD, M.F.; RICARD, M.F.; VIGLIZZO, E.F.; VÁZQUEZ-AMÁBILE, G.; VIGLIZZO, E.F.; VÁZQUEZ-AMÁBILE, G.; TABOADA, M.A.
Revista:
THE SCIENCE OF TOTAL ENVIRONMENT
Editorial:
Elsevier B.V.
Referencias:
Año: 2019 vol. 661 p. 531 - 542
ISSN:
0048-9697
Resumen:
Assuming a steady state between carbon (C) gains and losses, greenhouse gases (GHG) inventories that follow a widely used simplified procedure (IPCC Tier 1) tend to underestimate the capacity of soils in grazing-land to sequester C. In this study we compared the C balance reported by (i) national inventories that followed the simplified method (Tier 1) of IPCC (1996/2006), with (ii) an alternative estimation derived from the meta-analysis of science-based, peer-reviewed data. We used the global databases (i) EDGAR 4.2 to get data on GHG emissions due to land conversion and livestock/crop production, and (ii) HYDE 3.1 to obtain historical series on land-use/land cover (LULC). In terms of sequestration, our study was focused on C storage as soil organic carbon (SOC) in rural lands of four countries (Argentina, Brazil, Paraguay and Uruguay) within the so-called MERCOSUR region. Supported by a large body of scientific evidence, we hypothesized that C gains and losses in grazing lands are not in balance and that C gains tend to be higher than C losses at low livestock densities. We applied a two-way procedure to test our hypothesis: i) a theoretical one based on the annual conversion of belowground biomass into SOC; and ii) an empirical one supported by peer-reviewed data on SOC sequestration. Average figures from both methods were combined with LULC data to reassess the net C balance in the study countries. Our results show that grazing lands generate C surpluses that could not only offset rural emissions, but could also partially or totally offset the emissions of non-rural sectors. The potential of grazing lands to sequester and store soil C should be reconsidered in order to improve assessments in future GHG inventory reports.