Variations in photosynthesis still cause substantial uncertainties in predicting photosynthetic CO2 uptake rates and monitoring plant stress. Changes in actual photosynthesis that are not related to greenness of vegetation are difficult to measure by reflectance based optical remote sensing techniques. Several activities are underway to evaluate the sun-induced fluorescence signal on the ground and on a coarse spatial scale using space-borne imaging spectrometers. Intermediate-scale observations using airborne-based imaging spectroscopy, which are critical to bridge the existing gap between small-scale field studies and global observations, are still insufficient. Here we present the first validated maps of sun-induced fluorescence in that critical, intermediate spatial resolution, employing the novel airborne imaging spectrometer HyPlant. HyPlant has an unprecedented spectral resolution, which allows for the first time quantifying sun-induced fluorescence fluxes in physical units according to the Fraunhofer Line Depth Principle that exploits solar and atmospheric absorption bands. Maps of sun-induced fluorescence show a large spatial variability between different vegetation types, which complement classical remote sensing approaches. Different crop types largely differ in emitting fluorescence that additionally changes within the seasonal cycle and thus may be related to the seasonal activation and deactivation of the photosynthetic machinery. We argue that sun-induced fluorescence emission is related to two processes: (i) the total absorbed radiation by photosynthetically active chlorophyll and (ii) the functional status of actual photosynthesis and vegetation stress. Abstract Variations in photosynthesis still cause substantial uncertainties in predicting photosynthetic CO 2 uptake rates and monitoring plant stress. Changes in actual photosynthesis that are not related to greenness of vegetation are difficult to measure by reflectance based optical remote sensing techniques. Several activities are underway to evaluate the sun-induced fluorescence signal on the ground and on a coarse spatial scale using space-borne imaging spectrometers. Intermediate-scale observations using airborne-based imaging spectroscopy, which are critical to bridge the existing gap between small-scale field studies and global observations, are still insufficient. Here we present the first validated maps of sun-induced fluorescence in that critical, intermediate spatial resolution, employing the novel airborne imaging spectrometer HyPlant. HyPlant has an unprecedented spectral resolution, which allows for the first time quantifying sun-induced fluorescence fluxes in physical units according to the Fraunhofer Line Depth Principle that exploits solar and atmospheric absorption bands. Maps of sun-induced fluorescence show a large spatial variability between different vegetation types, which complement classical remote sensing approaches. Different crop types largely differ in emitting fluorescence that additionally changes within the seaso...

Hyperspectral imaging sensors are promising tools for monitoring crop plants or vegetation in different environments. Information on physiology, architecture or biochemistry of plants can be assessed non-invasively and on different scales. For instance, hyperspectral sensors are implemented for stress detection in plant phenotyping processes or in precision agriculture. Up to date, a variety of non-imaging and imaging hyperspectral sensors is available. The measuring process and the handling of most of these sensors is rather complex. Thus, during the last years the demand for sensors with easy user operability arose. The present study introduces the novel hyperspectral camera Specim IQ from Specim (Oulu, Finland). The Specim IQ is a handheld push broom system with integrated operating system and controls. Basic data handling and data analysis processes, such as pre-processing and classification routines are implemented within the camera software. This study provides an introduction into the measurement pipeline of the Specim IQ as well as a radiometric performance comparison with a well-established hyperspectral imager. Case studies for the detection of powdery mildew on barley at the canopy scale and the spectral characterization of Arabidopsis thaliana mutants grown under stressed and non-stressed conditions are presented.

[1] We present a new methodology to acquire, interpret, and store stratigraphic and structural information from paleoseismic exposures. For this study we employed portable hyperspectral cameras to acquire field-based visible near-infrared (VNIR) and short-wave infrared (SWIR) high spatial/spectral resolution images. We first analyzed 400 small sediments cores using a hand-held, single-pixel spectrometer (VNIR-SWIR) to determine the feasibility of the method and to assess its potential problems. We then acquired high-spatial resolution (submillimeter) spectral data of a large sample (60 Â 60 cm) and four cores (7.5 Â 60 cm) of faulted sediments from a paleoseismic excavation using portable push broom AISA hyperspectral scanner. These data, which contain 244 (VNIR) and 245 (SWIR) narrow contiguous spectral bands between 400 and 1000 and 960 to 2403 nm, respectively, were processed to obtain the reflectance spectra at each pixel. In this study we are focusing on the analysis of the short-wave infrared data sets (SWIR). The SWIR data were transformed into relative reflectance and geometrically corrected and processed with well-known imaging processing algorithms. Selected spectra were then used to create false color composite images that best display the faulted stratigraphy. We compared the hyperspectral images to those recorded by a digital camera as well as directly to the field sample and show that the reflectance properties of the materials in the SWIR region cannot only enhance the visualization of the sedimentary layers and other features that are not obvious to the human eye but can also make visible many detailed features that were not visible in the digital photography. This new data collection and interpretation methodology, herein termed field imaging spectroscopy, makes available, for the first time, a tool to quantitatively analyze paleoseismic and stratigraphic information. In addition, hyperspectral data sets in the visible short-wave infrared spectral range provide a better alternative for data storage. The reflectance spectra at each pixel of the images provide unbiased compositional information that can be processed in a variety of ways to assist with the interpretation of stratigraphy and structure at a site.Citation: Ragona, D., B. Minster, T. Rockwell, and J. Jussila (2006), Field imaging spectroscopy: A new methodology to assist the description, interpretation, and archiving of paleoseismological information from faulted exposures,

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A new compact Specim IQ hyperspectral camera working in the 400-1000 nm range has been launched on the market. Its use in the investigation of different artworks and under diverse environmental conditions will be presented.