California Institute of Technology (CalTech), Pasadena, CA (United States); Edgewater Federal Solutions/OSTI
California Institute of Technology (CalTech), Pasadena, CA (United States); Univ. of California, Los Angeles, CA (United States)
California Institute of Technology (CalTech), Pasadena, CA (United States); USDA Forest Service, Rio Piedras (Puerto Rico); Embrapa Informática Agropecuária, Campinas (Brazil)
California Institute of Technology (CalTech), Pasadena, CA (United States)
Harvard Univ., Cambridge, MA (United States)
NASA Goddard Space Flight Center, Greenbelt, MD (United States)
Univ. de Lorraine, Nancy (France)
Univ. of California, Irvine, CA (United States); Woods Hole Research Center, MA (United States); Inst. de Pesquisa Ambiental da Amazônia (Brazil)
Inst. National de Recherche en Agriculture, Kourou (France)
Univ. des Antilles, Univ. de Guyane, Kourou (France)
Selective logging, fragmentation, and understory fires directly degrade forest structure and composition. However, studies addressing the effects of forest degradation on carbon, water, and energy cycles are scarce. Here, we integrate field observations and high-resolution remote sensing from airborne lidar to provide realistic initial conditions to the Ecosystem Demography Model (ED-2.2) and investigate how disturbances from forest degradation affect gross primary production (GPP), evapotranspiration (ET), and sensible heat flux (H). We used forest structural information retrieved from airborne lidar samples (13,500 ha) and calibrated with 817 inventory plots (0.25 ha) across precipitation and degradation gradients in the eastern Amazon as initial conditions to ED-2.2 model. Our results show that the magnitude and seasonality of fluxes were modulated by changes in forest structure caused by degradation. During the dry season and under typical conditions, severely degraded forests (biomass loss ≥66%) experienced water stress with declines in ET (up to 34%) and GPP (up to 35%) and increases of H (up to 43%) and daily mean ground temperatures (up to 6.5°C) relative to intact forests. In contrast, the relative impact of forest degradation on energy, water, and carbon cycles markedly diminishes under extreme, multiyear droughts, as a consequence of severe stress experienced by intact forests. Our results highlight that the water and energy cycles in the Amazon are driven by not only climate and deforestation but also the past disturbance and changes of forest structure from degradation, suggesting a much broader influence of human land use activities on the tropical ecosystems.
Longo, Marcos, et al. "Impacts of Degradation on Water, Energy, and Carbon Cycling of the Amazon Tropical Forests." Journal of Geophysical Research. Biogeosciences, vol. 125, no. 8, Jun. 2020. https://doi.org/10.1029/2020jg005677
Longo, Marcos, Saatchi, Sassan, Keller, Michael, et al., "Impacts of Degradation on Water, Energy, and Carbon Cycling of the Amazon Tropical Forests," Journal of Geophysical Research. Biogeosciences 125, no. 8 (2020), https://doi.org/10.1029/2020jg005677
@article{osti_1816839,
author = {Longo, Marcos and Saatchi, Sassan and Keller, Michael and Bowman, Kevin and Ferraz, António and Moorcroft, Paul R. and Morton, Douglas C. and Bonal, Damien and Brando, Paulo and Burban, Benoît and others},
title = {Impacts of Degradation on Water, Energy, and Carbon Cycling of the Amazon Tropical Forests},
annote = {Selective logging, fragmentation, and understory fires directly degrade forest structure and composition. However, studies addressing the effects of forest degradation on carbon, water, and energy cycles are scarce. Here, we integrate field observations and high-resolution remote sensing from airborne lidar to provide realistic initial conditions to the Ecosystem Demography Model (ED-2.2) and investigate how disturbances from forest degradation affect gross primary production (GPP), evapotranspiration (ET), and sensible heat flux (H). We used forest structural information retrieved from airborne lidar samples (13,500 ha) and calibrated with 817 inventory plots (0.25 ha) across precipitation and degradation gradients in the eastern Amazon as initial conditions to ED-2.2 model. Our results show that the magnitude and seasonality of fluxes were modulated by changes in forest structure caused by degradation. During the dry season and under typical conditions, severely degraded forests (biomass loss ≥66%) experienced water stress with declines in ET (up to 34%) and GPP (up to 35%) and increases of H (up to 43%) and daily mean ground temperatures (up to 6.5°C) relative to intact forests. In contrast, the relative impact of forest degradation on energy, water, and carbon cycles markedly diminishes under extreme, multiyear droughts, as a consequence of severe stress experienced by intact forests. Our results highlight that the water and energy cycles in the Amazon are driven by not only climate and deforestation but also the past disturbance and changes of forest structure from degradation, suggesting a much broader influence of human land use activities on the tropical ecosystems.},
doi = {10.1029/2020jg005677},
url = {https://www.osti.gov/biblio/1816839},
journal = {Journal of Geophysical Research. Biogeosciences},
issn = {ISSN 2169-8953},
number = {8},
volume = {125},
place = {United States},
publisher = {American Geophysical Union},
year = {2020},
month = {06}}
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); NGEE-TRPC (Next-Generation Ecosystem
Experiments – Tropics)https://doi.org/10.15486/ngt/1255260