Monitoring of Landfill Leachate Dispersion Using Reflectance Spectroscopy and Ground-Penetrating Radar

Abstract

The utility of ground-penetrating radar and reflectance spectroscopy in the monitoring of landfill sites has been investigated. Strong correlations between red edge inflection position and chlorophyll and heavy metal concentrations have been demonstrated from grassland species affected by leachate contamination of the soil adjacent to the landfill test site. This study demonstrated that reflectance spectroscopy can identify vegetation affected by leachate-contaminated soil at a range of spatial resolutions. To identify the vegetation affected by leachate contamination, the spectroradiometer must have contiguous bands at sufficient spectral resolution over the critical wave range that measures chlorophyll absorption and the red edge (between 650 and 750 nm). The utility of ground-penetrating radar data to identify leachate escaping from breakout points in the contaminant wall has also been demonstrated. An integrated approach using these techniques, combined with field and borehole sampling and contaminant migration modeling, offers a possible cost-effective monitoring approach for landfill sites.

Monitoring plant response to phenanthrene using the red edge of canopy hyperspectral reflectance

“…Environmental pollution affects plant physiology and growth such as biomass (Rosso et al, 2005;Splajt et al, 2003;Zhu et al, 2013) and chlorophyll content (Mishra et al, 2012;Newete et al, 2014). These parameters are closely related to the change in the canopy reflectance spectra (Rosso et al, 2005;Splajt et al, 2003;Zhu et al, 2013).…”

“…These parameters are closely related to the change in the canopy reflectance spectra (Rosso et al, 2005;Splajt et al, 2003;Zhu et al, 2013). Therefore, remote sensing can characterize vegetation stress by recording the spectral signals of plants growing in the polluted environment Zhu et al, 2013).…”

“…Therefore, remote sensing can characterize vegetation stress by recording the spectral signals of plants growing in the polluted environment Zhu et al, 2013). Under metal and air pollution, the strong correlation is observed between the spectral changes and leaf chlorophyll concentrations (Newete et al, 2014;Splajt et al, 2003). However, many factors control the variation of leaf and canopy reflectance.…”

“…When monitoring vegetation pollution, early studies investigating red edge identified the wavelength corresponding to the maximum first derivative of reflectance. This wavelength is defined as the Red Edge Position (REP) or Red Edge Inflection Point (REIP) (Splajt et al, 2003;Ustin et al, 2009). However, the Red Edge Slope (RES) and Area (REA), defined as the maximum of the first derivative and the area under the derivative curve in the region of red edge remains less well studied, because the calculation of these two parameters requires information of high spectral resolution.…”

“…The shift of the red edge position is associated with heavy metal pollution in soils Splajt et al, 2003) and air pollution (Manzo et al, 2013). However, organic pollutants in soils have been rarely studied using the red edge.…”