Spectrometric analyses in comparison to the physiological condition of heavy metal stressed floodplain vegetation in a standardised experiment

Abstract

Floodplain ecosystems are affected by flood dynamics, nutrient supply as well as anthropogenic activities.Heavy metal pollution poses a serious environmental challenge. Pollution transfer from the soil to vegetation isstill present at the central location of Elbe River, Germany. The goal of this study was to assess and separatethe current heavy metal contamination of the floodplain ecosystem, using spectrometric field and laboratorymeasurements. A standardized pot experiment with floodplain vegetation in differently contaminated soils pro-vided the basis for the measurements. The dominant plant types of the floodplains are:Urtica dioica,PhalarisarundinaceaandAlopecurus pratensis, these were also chemically analysed. Various vegetation indices andmethods were used to estimate the red edge position, to normalise the spectral curve of the vegetation and toinvestigate the potential of different methods for separating plant stress in floodplain vegetation. The main taskwas to compare spectral bands during phenological phases to find a method to detect heavy metal stress inplants. A multi-level algorithm for the curve parameterisation was developed. Chemo-analytical and ecophys-iological parameters of plants were considered in the results and correlated with spectral data. The results ofthis study show the influence of heavy metals on the spectral characteristics of the focal plants. The developedmethod (depth CR1730) showed significant relationship between the plants and the contamination.