Boine, Judith
OPTICAL PROPERTIES OF OPEN CAST LIGNITE MINING LAKES IN CENTRAL GERMANY
Judith BOINE, Cornelia GLABER
Martin Luther University Halle Wittenberg, Germany
Institute of Geography
boine@geographie.uni-halle.de
glaesser@geographie.uni-halle.de
KEY WORDS: Dynamic processes, Ecosystems, Hyperspectral, Monitoring.
ABSTRACT
The aim of the study is the characterisation of the optical properties of mining lakes. These optical properties will be
used to the classification of remote sensing data and the spatial and temporal monitoring of these lakes.
Absorption properties of yellow substance and tripton were measured in the laboratory. The backscattering properties of
tripton were retrieved by the measured reflectance spectra and known backscattering spectra of water and
phytoplankton. The absorption measurements and the averaged backscattering properties were used to simulate the
measured reflectance spectra of mining lakes.
It will be shown that the optical properties of mining lakes are very different to natural inland water. Furthermore
variations exist between the different types of mining lakes too. At the basis of the different absorption and
backscattering properties of tripton mining lakes were classified in four groups in dependency of the pH value and the
inorganic content of the suspended matter. The modelled reflectance spectra are quite similar to the modelled
reflectance spectra.
KURZFASSUNG
Ziel dieser Untersuchungen ist die Charakterisierung der optischen Eigenschaften von Tagebaurestseen, welche für die
Klassifizierung von Fernerkundungsdaten und ein Monitoring dieser Seen Anwendung finden sollen.
Das Methodenspektrum umfasst die Bestimmung der Absorptionseigenschaften von Gelbstoff und Tripton im Labor,
sowie Messungen des Reflexionsgrades im Feld. Mit Hilfe der gemessenen Reflexionsspektren und den bekannten
Rückstreuspektren von Wasser und Phytoplankton wurden die Rückstreueigenschaften des Triptons berechnet. Aus den
Absorptionsspektren und den gemittelten Rückstreuspektren erfolgte die Modellierung der Reflexionsspektren für
verschiede Seen.
Es kann gezeigt werden, dass die optischen Eigenschaften der Tagebaurestseen sich einerseits signifikant von denen
natürlicher Binnengewásser unterscheiden, es aber auch zwischen den Tagebaurestseen Unterschiede gibt. Auf
Grundlage der unterschiedlichen Absorptions- und Rückstreueigenschaften von Tripton wurden die Tagebaurestseen in
Abhängigkeit vom pH-Wert und dem prozentualen Anteil von anorganischer Substanz in vier Gruppen untergeteilt. Die
modellierten Reflexionsspektren sind den gemessenen Reflexionsspektren sehr ähnlich.
1 INTRODUCTION
Remote sensing methods enable the estimation of water quality parameters in inland and coastal waters because the
optical properties of these waters are known. Remote sensing methods for mining lakes exist only few experiences and
optical properties of mining lakes are not available. Therefore the optical properties have to investigate for a successful
development of remote sensing methods.
The applications of remote sensing methods of mining lakes are necessary for the spatial and temporal monitoring of
hydrochemical and hydrobiological data and for a control of water quality. This is important since mining lakes
especially acid mine lakes are a world-wide existing problem, because of the acid mine drainage (AMD) system. The
oxidation of pyrite and marcasite, minerals that are commonly associated with lignite, and the ascending of ground
water or the flooding with surface water were founded the AMD system. The sediment chemistry and the kind of
flooding (ground or surface water) are important for the chemical and biological development of mining lakes and leads
to a high dynamic in there properties.
198 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.
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