Next Article in Journal
Modeling Surface Energy Fluxes over a Dehesa (Oak Savanna) Ecosystem Using a Thermal Based Two Source Energy Balance Model (TSEB) II—Integration of Remote Sensing Medium and Low Spatial Resolution Satellite Images
Previous Article in Journal
Estimating Vegetation Water Content and Soil Surface Roughness Using Physical Models of L-Band Radar Scattering for Soil Moisture Retrieval
Open AccessArticle

A MODIS Photochemical Reflectance Index (PRI) as an Estimator of Isoprene Emissions in a Temperate Deciduous Forest

1
Consejo Superior de Investigaciones Científicas (CSIC), Global Ecology Unit CREAF-CSIC-UAB, 08193 Bellaterra, Catalonia, Spain
2
CREAF, 08193 Cerdanyola del Vallès, Catalonia, Spain
3
Department of Earth System Science, University of California, Irvine, CA 92697, USA
4
Department of Environmental Science and Studies, DePaul University, Chicago, IL 60614, USA
5
Institute of Atmospheric and Cryospheric Sciences, University of Innsbruck, A-6020 Innsbruck, Austria
6
School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0988, USA
7
Department of Forestry, University of Missouri, Columbia, MO 65211, USA
8
Oak Ridge National Lab., Oak Ridge, TN 37830, USA
9
Center of Excellence PLECO, Biology Department, University of Antwerp, BE-2610 Wilrijk, Belgium
*
Author to whom correspondence should be addressed.
Remote Sens. 2018, 10(4), 557; https://doi.org/10.3390/rs10040557
Received: 24 January 2018 / Revised: 15 March 2018 / Accepted: 30 March 2018 / Published: 4 April 2018
(This article belongs to the Section Biogeosciences Remote Sensing)
The quantification of isoprene and monoterpene emissions at the ecosystem level with available models and field measurements is not entirely satisfactory. Remote-sensing techniques can extend the spatial and temporal assessment of isoprenoid fluxes. Detecting the exchange of biogenic volatile organic compounds (BVOCs) using these techniques is, however, a very challenging goal. Recent evidence suggests that a simple remotely sensed index, the photochemical reflectance index (PRI), which is indicative of light-use efficiency, relative pigment levels and excess reducing power, is a good indirect estimator of foliar isoprenoid emissions. We tested the ability of PRI to assess isoprenoid fluxes in a temperate deciduous forest in central USA throughout the entire growing season and under moderate and extreme drought conditions. We compared PRI time series calculated with MODIS bands to isoprene emissions measured with eddy covariance. MODIS PRI was correlated with isoprene emissions for most of the season, until emissions peaked. MODIS PRI was also able to detect the timing of the annual peak of emissions, even when it was advanced in response to drought conditions. PRI is thus a promising index to estimate isoprene emissions when it is complemented by information on potential emission. It may also be used to further improve models of isoprene emission under drought and other stress conditions. Direct estimation of isoprene emission by PRI is, however, limited, because PRI estimates LUE, and the relationship between LUE and isoprene emissions can be modified by severe stress conditions. View Full-Text
Keywords: drought; GPP; isoprene; LUE; MEGAN; MODIS; PRI; photorespiration; reducing power; substrate availability drought; GPP; isoprene; LUE; MEGAN; MODIS; PRI; photorespiration; reducing power; substrate availability
Show Figures

Graphical abstract

MDPI and ACS Style

Filella, I.; Zhang, C.; Seco, R.; Potosnak, M.; Guenther, A.; Karl, T.; Gamon, J.; Pallardy, S.; Gu, L.; Kim, S.; Balzarolo, M.; Fernandez-Martinez, M.; Penuelas, J. A MODIS Photochemical Reflectance Index (PRI) as an Estimator of Isoprene Emissions in a Temperate Deciduous Forest. Remote Sens. 2018, 10, 557.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map

1
Back to TopTop