Exploring the Potential of Light Use Efficiency Derived from Eddy Covariance and Reflectance Measurements for Spatial Simulations of Gross Primary Production

0522663 - ÚVGZ 2020 CZ eng A - Abstrakt
Raj, Rahul - Homolová, Lucie - Lukeš, Petr - Kováč, Daniel
Exploring the Potential of Light Use Efficiency Derived from Eddy Covariance and Reflectance Measurements for Spatial Simulations of Gross Primary Production.
11th EARSeL SIG Imaging Spectroscopy Workshop. Brno: Ústav výzkumu globální změny AV ČR, 2019 - (Homolová, L.). s. 82-83
[EARSel SIG IMAGING SPECTROSCOPY WORKSHOP BRNO /11./. 06.02.2019-08.02.2019, Brno]
Institucionální podpora: RVO:86652079
Klíčová slova: spruce forest * flux tower * modelling * gross primary productivity
Obor OECD: Remote sensing

Light use efficiency (LUE) model based on remote sensing provide a promising tool for monitoring spatial and temporal variations of CO2 uptake (gross primary production; GPP) by terrestrial vegetation. GPP is simulated by the LUE model as a product of light use efficiency term and absorbed photosynthetically active radiation (PAR). Absorbed PAR is calculated as a product of incident PAR and the fraction of incident PAR absorbed by the vegetation (fAPAR). The accuracy of GPP simulation by the LUE model, however, depends upon how well the LUE term is quantified. Most of the current studies rely on the constant value of the LUE term for a particular land cover type. However, the spatial heterogeneity in the LUE term within a land cover type due to the different species compositions was well recognized. Temporal change in the LUE term is also apparent due to change in the environmental factors such as air temperature, soil moisture, and vapor pressure deficit. In this study, we considered both the spatial and temporal distributions of the LUE term. At the spruce dominated forest site Bílý Kříž, Czech Republic, continuous half-hourly measurements of net ecosystem exchange (NEE) are being made at the flux tower using eddy covariance technique. In addition, a spectrometer is also installed at the top of the tower to collect time series of spectral reflectance of a small canopy sector at a 5-minute interval.
Trvalý link: http://hdl.handle.net/11104/0307117