A Gis-Supported Multivariate Statistical Analysis of Relationships Among Stream Water Chemistry, Geology and Land Use in Baden-Württemberg, Germany

The present study was carried out to analyse and identify relationships among stream water chemistry, land use, and geology in Baden-Württemberg, a federal state in the south-west of Germany. The investigation is based on data from 88 monitoring stations, which cover almost the whole area of Baden-Württemberg. The database on water chemistry includes 21 parameters such as major cations, anions, heavy metals, dissolved organic carbon, pH, acid neutralization capacity, and conductivity. The study area is classified into 16 different land use categories and 12 types of geological formations. Using multivariate statistical methods (factor analysis), the relationships among different parameters were revealed by identifying ten uncorrelated factors. The data analysis indicates a complex interaction among stream water chemistry, lithologic composition of the geological formations, and land use type, with an intricate fingerprintings of the different parameters. The most important factors in terms of the represented variance are the main mineralization of the stream water (due to interaction with the geological underground) and anthropogenic nutrients introduced by different agricultural activities. Based on the results of factor analysis (factor score), the stream water chemistry is regionalized using a Geographic Information System (ArcView).