0000000001330681
AUTHOR
Patrick Hostert
A Comparison of Advanced Regression Algorithms for Quantifying Urban Land Cover
Quantitative methods for mapping sub-pixel land cover fractions are gaining increasing attention, particularly with regard to upcoming hyperspectral satellite missions. We evaluated five advanced regression algorithms combined with synthetically mixed training data for quantifying urban land cover from HyMap data at 3.6 and 9 m spatial resolution. Methods included support vector regression (SVR), kernel ridge regression (KRR), artificial neural networks (NN), random forest regression (RFR) and partial least squares regression (PLSR). Our experiments demonstrate that both kernel methods SVR and KRR yield high accuracies for mapping complex urban surface types, i.e., rooftops, pavements, gras…
CEFLES2: The remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the oxygen absorption bands
The CEFLES2 campaign during the Carbo Europe Regional Experiment Strategy was designed to provide simultaneous airborne measurements of solar induced fluorescence and CO<sub>2</sub> fluxes. It was combined with extensive ground-based quantification of leaf- and canopy-level processes in support of ESA's Candidate Earth Explorer Mission of the "Fluorescence Explorer" (FLEX). The aim of this campaign was to test if fluorescence signal detected from an airborne platform can be used to improve estimates of plant mediated exchange on the mesoscale. Canopy fluorescence was quantified from four airborne platforms using a combination of novel sensors: (i) the prototype ai…
Remote sensing of sun-induced fluorescence to improve modeling of diurnal courses of gross primary production (GPP)
Terrestrial gross primary production (GPP) is an important parameter to explore and quantify carbon fixation by plant ecosystems at various scales. Remote sensing (RS) offers a unique possibility to investigate GPP in a spatially explicit fashion; however, budgeting of terrestrial carbon cycles based on this approach still remains uncertain. To improve calculations, spatio-temporal variability of GPP must be investigated in more detail on local and regional scales. The overarching goal of this study is to enhance our knowledge on how environmentally induced changes of photosynthetic light-use efficiency (LUE) are linked with optical RS parameters. Diurnal courses of sun-induced fluorescence…
Mapping Cerrado woody plant traits with spaceborne hyperspectral data
The Cerrado (Brazilian savannah), is the most diverse of all of the world's savannahs. While holding a high diversity and endemism of species, this biome is mostly unprotected and understudied. Also, recent studies have given focus on the importance of species traits, and on the need to incorporate them into biodiversity monitoring and conservation. In this paper, we used woody plant inventory data, plant trait data, and spaceborne hyperspectral (Hyperion) data to map woody plant traits in two study sites in the Cerrado. To this aim, we applied a Sparse Generalized Dissimilarity Modelling (SGDM) approach for modelling the species turnover on each site. Matrix calculations were applied to as…