Microbial Ecology of a Brackish Water Environment

A knowledge, which is as accurate as possible of microbial ecology is indispensible for ecosystem research and environmental protection. This is particularly true for coastal waters, whereby brackish water areas occupy a special position. After several years of preliminary studies on the composition and distribution of the micro flora -algae, fungi, and bacteria -a comprehensive investigation on the primary production, bacterial development and microbial uptake and decom­ position of substances in the Kie1 Bight was carried out, during which ten scientists from the Institut fUr Meereskunde ofKiel University participated. Here forthe first time numerous hydrographical, chemical and microbiological parameters could be measured on the same water samples. The aim of this joint project was to gain an insight into the manifold functions of the microorganisms in the uptake and degradation of organic substances and in the connections between pollution, production, and remineralization. The results ofthe investigations led not only to new knowledge of the role ofthe microorganisms in the brackish water ecosystem, but also to a revision of earlier conceptions, especially on the influence of wastes on the micro flora and its role in the self-purification of coastal waters. Such a time-limited investigation, however, cannot clarify all the questions on the complex relationships between the microorganisms and their biotope. Therefore, the present volume should also be understood as a stimulus for new and further-reaching research on the microbial ecology of coastal waters. Thereby the most important methods are described, as well as the practical experience obtained.

Contenu

1. Introduction.- References.- 2. The Kiel Bight as Research Area.- References.- 3. Hydrographic Conditions.- 3.1 The Baltic Sea as an Estuary.- 3.2 General Hydrographical Features of the Baltic.- 3.3 The Kiel Bight.- 3.4 The Kiel Fjord.- 3.5 Study Period 1974/75.- References.- 4. Oxygen and Some Inorganic Nutrients.- 4.1 Material and Methods.- 4.2 Oxygen.- 4.3 Inorganic Nutrients.- 4.3.1 Ammonia.- 4.3.2 Nitrite.- 4.3.3 Nitrate.- 4.3.4 Orthophosphate.- 4.4 The Annual Cycle of Nutrients.- References.- 5. Seston and Its Main Components.- 5.1 Seston.- 5.2 Chlorophyll a.- 5.3 Particulate Carbon and Nitrogen.- 5.4 Protein.- 5.5 Carbohydrates.- 5.6 Lipids.- 5.7 Adenosine Triphosphate (ATP).- 5.8 Organic and Inorganic Matter.- 5.9 Fraction of Plankton and Detritus in Organic Matter.- 5.10 Percentual Composition of Seston.- References.- 6. Determination of Organic Substances and Respiration Potential.- 6.1 Description and Application of the Chemical Oxygen Demand (COD) Method.- 6.2 Description and Application of the Biochemical Oxygen Demand (BOD) Method.- 6.3 Description and Application of Dehydrogenase Activity (DHA) Determination as a Measure for Potential Respiration.- References.- 7. Primary Production.- 7.1 Material and Methods.- 7.2 Primary Production in the Kiel Fjord and Different Areas of the Kiel Bight.- References.- 8. Plankton Populations.- 8.1 Plankton Populations of the Kiel Bight.- 8.2 Phytoplankton Populations During the Study Period 1974/75 81 References.- 9. Fungi.- 9.1 Lower Fungi (Mastigomycotina).- 9.2 Yeasts.- 9.3 Lignicolous Fungi (Ascomycotina, Deuteromycotina).- References.- 10. Estimation of Bacterial Number and Biomass by Epifluorescence Microscopy and Scanning Electron Microscopy.- 10.1 Staining Technique for the Epifluorescence Microscopic Count.- 10.2 Preparation of Specimens for Scanning Electron Microscopy.- 10.3 Preliminary Examinations.- 10.4 Examination of the Kiel Fjord and Kiel Bight 1974/75.- 10.4.1 Regional and Seasonal Distribution of Bacteria.- 10.4.2 Estimation of Bacterial Cell Sizes and Biomass.- 10.4.3 Bacteria Attached to Detritus.- References.- 11. Regional and Seasonal Distribution of Saprophytic and Coliform Bacteria.- 11.1 Material and Methods.- 11.2 Distribution of Marine, Brackish Water and Fresh Water Bacteria in the Water.- 11.3 Distribution of Marine, Brackish Water and Fresh Water Bacteria in the Sediments.- References.- 12. Distribution of Special Physiological Bacteria Groups.- 12.1 Material and Methods.- 12.2 Results and Discussion.- References.- 13. Numerical Taxonomy and Character Analysis of Saprophytic Bacteria Isolated from the Kiel Fjord and the Kiel Bight.- 13.1 Material and Methods.- 13.1.1 Isolation of the Bacteria Strains.- 13.1.2 Morphological, Physiological and Biochemical Tests.- 13.1.3 Numerical Taxonomy.- 13.1.4 Classifying by Key Diagnostics.- 13.2 Results.- 13.2.1 Numerical Taxonomy of the HMOs.- 13.2.2 Comparison of the Median Strains and Ungrouped Strains by Numerical Taxonomy.- 13.2.3 Classifying of Bacterial Strains by Using Determination Schemes.- 13.2.4 Analysis of the Frequency of Characters.- 13.3 Discussion.- References.- 14. Analysis of Actively Metabolizing Bacterial Populations with the Autoradiographic Method.- 14.1 Material and Methods.- 14.1.1 Micro-Autoradiographic Method for the Determination of Active Bacteria Cells.- 14.1.2 Description of a Macro-Autoradiographic Method to Determine Physiological Groups of Active Bacteria Colonies.- 14.2 Results.- 14.2.1 Annual Cycle of the Actively Metabolizing Heterotrophic Bacteria in the Kiel Fjord and the Kiel Bight.- 14.2.2 Distribution of Some Physiological Bacteria Groups in Different Brackish Water Biotopes.- 14.3 Discussion on the Role of Actively Metabolizing Bacteria in Brackish Water Areas.- References.- 15. Heterotrophic Activity.- 15.1 Material and Methods.- 15.1.1 Determination of Vmax, Tt, and (Kt + Sn).- 15.1.2 Determination of the Turnover Time of an Amino Acid Mixture.- 15.2 Horizontal and Vertical Distribution of the Heterotrophic Activity.- 15.2.1 Spatial Distribution of the Maximum Uptake Velocity.- 15.2.2 Spatial Distribution of the Sum of Transport "Constant" and Natural Substrate Concentration (Kt + Sn).- 15.2.3 Spatial Distribution of the Turnover Time.- 15.3 Seasonal Distribution of Heterotrophic Activity.- 15.3.1 Seasonal Distribution of Maximum Uptake Velocity.- 15.3.2 Seasonal Distribution of the Turnover Time.- 15.3.3 Seasonal Distribution of the Sum of Transport "Constant" and Natural Substrate Concentration (Kt + Sn).- References.- 16. Bacterial Growth Rates and Biomass Production.- 16.1 Material and Methods.- 16.1.1 Sampling Procedure and Processing the Samples.- 16.1.2 Assay Analysis.- 16.2 Growth Activity and Biomass Production.- 16.3 Generation Time and Influence of Temperature on Growth Activity.- 16.4 Influence of Quality of Water on Growth Activity.- 16.5 Discussion.- References.- 17. Nitrification.- 17.1 Material and Methods.- 17.2 Potential Activity for Nitrite Oxidation in the Kiel Fjord and the Kiel Bight.- 17.3 Discussion of the Results.- References.- 18. Desulfurication and Sulfur Oxidation.- References.- 19. Comparative Analysis of Data Measured in the Brackish Water of the Kiel Fjord and the Kiel Bight.- 19.1 Methods Applied for the Comparative Analysis of the Results.- 19.1.1 Two-State Correlation Analysis.- 19.1.2 Series Comparison.- 19.1.3 Time-Series Analysis.- 19.1.4 Arrangement of the Parameters Measured.- 19.1.5 Representation of the Results.- 19.2 Results.- 19.3 Discussion.- References.- 20. Conclusion.- References.