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The method of cluster analysis as a means for the structuring, classification and interpretation of multivariate data is represented in a survey of hierarchical and non-hierarchical procedures. The non-hierarchical potential method CLUPOT is described in a BASIC program and applied to the example of the daily variations of the heavy-metal concentrations in wastewater.  相似文献   

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Community Structures of Different Groundwater Habitats Investigated Using Methods of Molecular Biology The degradation of pollutants in groundwater and aquifers depends on microbiological and hydrogeochemical processes. To understand the transport and fate of anthropogenic compounds during bank filtration and artificial recharge of groundwater it is necessary to gain more information about the structure of microbial populations in these systems. The population structure of aerobic, anaerobic groundwater habitats and of water samples during artificial groundwater recharge was examined by 16S rDNA based analysis. Water and sediment samples were collected from a groundwater catchment area with artificial groundwater recharge near the river Ruhr in NW-Germany. 16S rRNA genes of mixed bacterial DNA from different samples were amplified by PCR (polymerase chain reaction) with eubacterial primer sequences. To reveal eubacterial population structure amplified PCR-products were separated by DGGE (denaturing gradient gel electrophoresis) on the basis of melting domain structure and nucleotide composition. DGGE patterns of groundwater enrichment cultures and groundwater samples were compared to demonstrate differences between the use of cultivation dependent and molecularbiological approaches. The DGGE pattern of groundwater is very complex and differs significantly from DGGE patterns of groundwater enrichment cultures characterized by a small number of distinct bands. This shows the small quantity of culturable microorganisms in groundwater eco-systems. Aerobic and anaerobic groundwater and sediment samples differ markedly in their DGGE profiles. Different hydrogeochemical zones of this groundwater catchment area are mirrowed by distinct DGGE patterns indicating changes in microbial community structure.Analysis of bacterial population structure in the course of artificial groundwater recharge shows identical DGGE patterns comparing surface water samples to samples taken be-fore gravel prefiltration and before sand filtration. In contrast the DGGE pattern of artificial recharged groundwater differs markedly, indicating significant changes in microbial population during underground passage.  相似文献   

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Zusammenfassung Eine statistische Analyse der geophysikalischen Potentialfelder, die durch Intensität und Frequenz der regionalen Anomalien bestimmt werden, liefert interessante Ergebnisse über die Struktur der Erdkruste. Im einzelnen können die Tiefe von horizontalen Diskontinuitäten, die Lage von vertikalen tektonischen Störungen, tektonische Vorzugsrichtungen als mittlere Richtungen der Anomalientrends und die mittlere Tiefe derCurie-Isotherme bestimmt werden. Die Grundlage der statistischen Untersuchungen stellt die Korrelationsanalyse dar. Die verschiedenen Methoden werden im einzelnen beschrieben.
Summary A statistical analysis of the geophysical potential fields, which are characterized by intensity and frequency ofthe regional anomalies, shows interesting results on the structure of the crust. Especially there may be determined the depth of horizontal discontinuities, tectonicmean directions as mean directions of anomaly trends and the mean depth of theCurie-point. The basis of the statistical investigations is the correlation-analysis. The several treatments are described in detail.


Mitteilung aus dem Geomagnetischen Institut der DAW, Potsdam, Nr. 264.  相似文献   

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