22 research outputs found
Globe-LFMC, a global plant water status database for vegetation ecophysiology and wildfire applications
Globe-LFMC is an extensive global database of live fuel moisture content (LFMC) measured from 1,383 sampling sites in 11 countries: Argentina, Australia, China, France, Italy, Senegal, Spain, South Africa, Tunisia, United Kingdom and the United States of America. The database contains 161,717 individual records based on in situ destructive samples used to measure LFMC, representing the amount of water in plant leaves per unit of dry matter. The primary goal of the database is to calibrate and validate remote sensing algorithms used to predict LFMC. However, this database is also relevant for the calibration and validation of dynamic global vegetation models, eco-physiological models of plant water stress as well as understanding the physiological drivers of spatiotemporal variation in LFMC at local, regional and global scales. Globe-LFMC should be useful for studying LFMC trends in response to environmental change and LFMC influence on wildfire occurrence, wildfire behavior, and overall vegetation health
Numerical simulation of tsunamis generated by caldera collapse during the 7.3 ka Kikai eruption, Kyushu, Japan
SAILHFlood: A radiative transfer model for flooded vegetation
In this manuscript we present a radiative transfer model for submerged vegetation called SAILHFlood. It simulates reflectance for a partial submerged canopy from vegetation variables, water level, measurement geometry and soil reflectance. It is a version of the proven SAILH model in which, two vegetation layers are included instead of one: the emerged vegetation layer and the submerged vegetation layer, for which the water attenuation is considered. The model validation was performed with a experiment in laboratory conditions varying leaf area index, water level and illumination and observation angles. A least square linear fit of simulated data used to reproduce measured data shows a satisfactory root mean square error (RMSE) of 0.0355, and a spectral angle of 0.2591 radians. The model could be applied to the diversity of vegetation found in flooded situations, both to understand spectral behavior of these environments under different scenarios and to estimate vegetation variables from model inversion.Fil: Beget, M. E.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Bettachini, Víctor. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Di Bella, Carlos Marcelo. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Baret, F.. Institut National de la Recherche Agronomique; Franci
Monoterpene emissions from three Nothofagus species in Patagonia, Argentina
Isoprenoid emissions have key roles in plant biology and plant interactions with the environment. Global emission inventories of isoprenoid emissions still lack information from a large number species, especially from South American vegetation other than the rainforest ecosystem. A study was conducted to identify the basal emission of isoprenoid under field conditions from three Nothofagus species. The three Nothofagus species were characterized as strong monoterpene emitters while the emission of isoprene was undetectable. The two deciduous species, N. pumilio and N. antarctica, had similar photosynthetic parameters, but monoterpene emission rate and, consequently, the fraction of photosynthetic carbon re-emitted in the atmosphere as monoterpenes, were more than three-fold higher in N. pumilio than in N. Antarctica. The evergreen species N. dombeyi showed intermediate values of both monoterpene emission rate and fraction of photosynthetic carbon re-emitted. The monoterpene emission spectrum was very similar among the three Nothofagus species screened, but clearly different from the spectrum reported in other monoterpene-emitting species of the Fagaceae family. The importance of these findings for atmospheric chemistry and phylogenic evolution are discussed
Relating Biophysical Parameters of Coastal Marshes to Hyperspectral Reflectance Data in the Bahia Blanca Estuary, Argentina
Salt marshes occupying the tidal fringe of estuaries and protected coasts provide valuable ecosystem services, and remote sensing is a powerful tool for their large scale monitoring. However, in order to apply remote sensing techniques to evaluate the ecological state of salt marshes, a deeper understanding is needed on the interactions between field biophysical parameters and the electromagnetic signal. The main objective of this work is to analyze and quantify the influence of different biophysical parameters characterizing stands of Spartina alterniflora marshes in the Bahia Blanca estuary, Argentina on their spectral response. Spectral reflectance at high resolution was measured in S. alterniflora canopies under natural conditions, manipulating standing biomass by means of successive harvestings. Reflectance data were acquired using a FieldSpec® sprectroradiometer (Analytical Spectral Devices, Inc.) in visible, near-infrared and shortwave infrared bands. Spectral indices including the Normalized Difference Vegetation Index (NDVI), were calculated for each biomass situation, leaf area index (LAI), percentage canopy cover (PCC), water content and soil properties were measured. LAI, PCC and biomass were positively correlated between them. As a general trend, as biomass decreased, absorption in red wavelengths increased and reflectance in near infrared decreased. Several indices explained the variability in LAI, biomass and PCC. For example, NDVIRouse had a positive regression with PCC (R2 = 0.80, N = 75) and LAI (R2 = 0.67, N = 75). Results indicate that LAI, biomass and PCC of Spartina alterniflora could be accurately determined from spectral data. Fil: Gonzalez Trilla, Gabriela Liliana. Universidad Nacional de San Martin. Instituto de Investigación e Ingenieria Ambiental. Laboratorio de Ecologia, Teledeteccion y Ecoinformática; ArgentinaFil: Pratolongo, Paula Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Beget, M. E.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigaciones de Recursos Naturales. Instituto de Clima y Agua; ArgentinaFil: Kandus, P.. Universidad Nacional de San Martin. Instituto de Investigación e Ingenieria Ambiental. Laboratorio de Ecologia, Teledeteccion y Ecoinformática; ArgentinaFil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Di Bella, Carlos Marcelo. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigaciones de Recursos Naturales. Instituto de Clima y Agua; Argentin
Globe-LFMC, a global plant water status database for vegetation ecophysiology and wildfire applications [Data Paper]
Globe-LFMC is an extensive global database of live fuel moisture content (LFMC) measured from 1,383 sampling sites in 11 countries: Argentina, Australia, China, France, Italy, Senegal, Spain, South Africa, Tunisia, United Kingdom and the United States of America. The database contains 161,717 individual records based on in situ destructive samples used to measure LFMC, representing the amount of water in plant leaves per unit of dry matter. The primary goal of the database is to calibrate and validate remote sensing algorithms used to predict LFMC. However, this database is also relevant for the calibration and validation of dynamic global vegetation models, eco-physiological models of plant water stress as well as understanding the physiological drivers of spatiotemporal variation in LFMC at local, regional and global scales. Globe-LFMC should be useful for studying LFMC trends in response to environmental change and LFMC influence on wildfire occurrence, wildfire behavior, and overall vegetation health