TY - JOUR

T1 - Gap formation and carbon cycling in the Brazilian Amazon

T2 - measurement using high-resolution optical remote sensing and studies in large forest plots

AU - Espirito-Santo, Fernando D. B.

AU - Keller, Michael M.

AU - Linder, Ernst

AU - Oliveira Junior, Raimundo C.

AU - Pereira, Cleuton

AU - Oliveira, Cleber G.

PY - 2014

Y1 - 2014

N2 - Background: The dynamics of gaps plays a role in the regimes of tree mortality, production of coarse woody debris (CWD) and the variability of light in the forest understory.Aims: To quantify the area affected by, and the carbon fluxes associated with, natural gap-phase disturbances in a tropical lowland evergreen rain forest by use of ground measurements and high-resolution satellite images.Methods: We surveyed two large forest inventory plots of 114 and 53 ha of the Tapajos National Forest (TNF) in the Brazilian Amazon during 2008 and 2009, respectively. We mapped all gaps and collected data on light availability, CWD stocks and tree mortality in the field. Gap location, canopy openness (CO) and leaf area index (LAI) estimated in the field were compared with two IKONOS-2 high-resolution satellite images acquired at approximately the time of the field measurements.Results: In the two large plots (167 ha total area) we found 96 gaps. The gaps represented 1.42% of the total area and gapsConclusions: We present the first statistics of CWD production based on gap size in the tropical forest literature. Tree mortality and CWD flux and the forest floor light environment were closely related to gap area. However, less than 30% of the annual tree mortality and CWD flux was associated with gaps, and gaps were difficult to detect using remote sensing methods because of the high proportion of shadow in the images. These results highlight the need for permanent plots in long-term carbon studies.

AB - Background: The dynamics of gaps plays a role in the regimes of tree mortality, production of coarse woody debris (CWD) and the variability of light in the forest understory.Aims: To quantify the area affected by, and the carbon fluxes associated with, natural gap-phase disturbances in a tropical lowland evergreen rain forest by use of ground measurements and high-resolution satellite images.Methods: We surveyed two large forest inventory plots of 114 and 53 ha of the Tapajos National Forest (TNF) in the Brazilian Amazon during 2008 and 2009, respectively. We mapped all gaps and collected data on light availability, CWD stocks and tree mortality in the field. Gap location, canopy openness (CO) and leaf area index (LAI) estimated in the field were compared with two IKONOS-2 high-resolution satellite images acquired at approximately the time of the field measurements.Results: In the two large plots (167 ha total area) we found 96 gaps. The gaps represented 1.42% of the total area and gapsConclusions: We present the first statistics of CWD production based on gap size in the tropical forest literature. Tree mortality and CWD flux and the forest floor light environment were closely related to gap area. However, less than 30% of the annual tree mortality and CWD flux was associated with gaps, and gaps were difficult to detect using remote sensing methods because of the high proportion of shadow in the images. These results highlight the need for permanent plots in long-term carbon studies.

KW - Amazon

KW - canopy opening

KW - coarse wood debris gaps

KW - leaf area index natural disturbances

KW - remote sensing

KW - tropical forest

KW - IKONOS

KW - TROPICAL RAIN-FOREST

KW - IKONOS SATELLITE-OBSERVATIONS

KW - COARSE WOODY DEBRIS

KW - CANOPY GAPS

KW - VEGETATION DYNAMICS

KW - NEOTROPICAL FOREST

KW - LARGE BLOWDOWNS

KW - LOGGED FORESTS

KW - UNITED-STATES

KW - TREEFALL GAPS

U2 - 10.1080/17550874.2013.795629

DO - 10.1080/17550874.2013.795629

M3 - Journal article

VL - 7

SP - 305

EP - 318

JO - Plant Ecology and Diversity

JF - Plant Ecology and Diversity

SN - 1755-0874

IS - 1-2

ER -