@Article{SousaHilWarMouLya:2017:PrReSe,
author = "Sousa, Celio Helder Resende de and Hilker, Thomas and Waring,
Richard and Moura, Yhasmin Mendes de and Lyapustin, Alexei",
affiliation = "{Oregon State University} and {Oregon State University} and
{Oregon State University} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {NASA Goddard Space Flight Center}",
title = "Progress in remote sensing of photosynthetic activity over the
amazon basin",
journal = "Remote Sensing",
year = "2017",
volume = "9",
number = "1",
pages = "48",
keywords = "Amazon, Drought, Eddy-flux, GPP, Light use efficiency, MAIAC,
MODIS, Photosynthesis, Sun-induced fluorescence, Tropical
forest.",
abstract = "Although quantifying the massive exchange of carbon that takes
place over the Amazon Basin remains a challenge, progress is being
made as the remote sensing community moves from using traditional,
reflectance-based vegetation indices, such as the Normalized
Difference Vegetation Index (NDVI), to the more functional
Photochemical Reflectance Index (PRI). This new index, together
with satellite-derived estimates of canopy light interception and
Sun-Induced Fluorescence (SIF), provide improved estimates of
Gross Primary Production (GPP). This paper traces the development
of these new approaches, compares the results of their analyses
from multiple years of data acquired across the Amazon Basin and
suggests further improvements in instrument design, data
acquisition and processing. We demonstrated that our estimates of
PRI are in generally good agreement with eddy-flux tower
measurements of photosynthetic light use efficiency (\ε) at
four sites in the Amazon Basin: r2 values ranged from 0.37 to 0.51
for northern flux sites and to 0.78 for southern flux sites. This
is a significant advance over previous approaches seeking to
establish a link between global-scale photosynthetic activity and
remotely-sensed data. When combined with measurements of
Sun-Induced Fluorescence (SIF), PRI provides realistic estimates
of seasonal variation in photosynthesis over the Amazon that
relate well to the wet and dry seasons. We anticipate that our
findings will steer the development of improved approaches to
estimate photosynthetic activity over the tropics.",
doi = "10.3390/rs9010048",
url = "http://dx.doi.org/10.3390/rs9010048",
issn = "2072-4292",
language = "en",
targetfile = "sousa_progress.pdf",
urlaccessdate = "01 maio 2024"
}