Tools and Methods
In situ Monitoring Tools
Ground based measurements on the different test sites include measurements to describe the natural background conditions as well as materials and their composition disseminated by water or wind directly or on diffuse pathways. To describe the local situation, parameters related to vegetation stands to soil properties (pH values, mineral content, etc.) and to weathering processes (spatial mosaic of primary and secondary mineral compositions) have to be measured or analysed in the field and/or in laboratory.
Field spectroradiometric measurements and Spectral Library: Based on the ground measurements libraries of the spectral signatures corresponding to different surface materials have to be set up to archive the measurements properly. This requires not only a correct documentation of the measurements, but also archiving ancillary data (measurement device used, information about calibration, etc.) have to be recorded. The development of well defined metadata concept is essential. DLR already operates a spectra library where all relevant data from flight campaigns and projects are archived. The concept developed so far can easily be enhanced to take the needs and requirements of the different test sites under investigations into account. Spectral library are essential for processing optical imagery and in particular hyperspectral images. At the end of the project, the spectral library will become part of the overall documentation of WP 2 and WP 3.
Based on an innovative method developed by Chudnovsky et al (2007) to assess quantitatively very small amounts of dust (from 0. 018-0.45 mg/cm2) using reflectance measurements, this concept will be applied to demonstration sites. This method will be applied first to the indoor environment that is closed to the mines. At the second stage this approach will be further developed to cover the outdoors environment and track after possible contamination direction and processes. The information will be projected on the high spatial and spectral resolution EO data for finding possible correlation with other spatial information. In this stage a dust spectral model will be developed in order to implement it on both the reflectance image and on a point reflectance domain measured at each building. GIS based methods to interpolate the point measurements into map will allow a precise recognition of small amount of dust in high spatial resolution domain over short time. This information will be also examined under temporal basis.
Chemical Model and 3D Characterization of the contaminated soils: Chemical and spectral information from many samples at selected sites will be used to generate quantitative spectral models to predict contamination. This information will be validated in the field (WP2) and if it will pass the uncertainty threshold, it will be applied to the High Spectral Resolution (HSR) reflectance/emmitance data. The models will be also used to describe the soil contaminated profile using Tel-Aviv University new assembly SpectraTool (3S-HED assembly) (Ben-Dor et al, 2008). This electrooptic sensor can be penetrated into very small drilling hole (“soil catheterization”) that the traditional needs to open boreholes. This information will be overlain on the surface mineral map generated previously from the HSR sensor enabling a 3D understanding of the contamination. The models and the SpectraTool will be delivered at the end of the project with a written manual on how to use them in the future using similar technology.