Hochwasser 2002

In August 2002, highly contaminated areas in the region of Bitterfeld, e.g. the floodplain of the creek Spittelwasser, as well as the adjacent regions of Jeßnitz and Raguhn, were submerged by the river Mulde. An input of mobilized contaminated sediments in residential areas was the matter of concern. The objective of the present study was to estimate the pollutants load on the basis of chemical and biological data and identify the sources of pollutants. Deposited sludge and flood water samples were assessed on the basis of biological and chemical analyses and in comparison with administrative reference values. The pollution of the investigated sites was rather heterogeneous. At several sites, tolerance limits of the German Klärschlammverordnung or the Bundesbodenschutzverordnung were clearly exceeded, e.g. for Pb, As and HCH. Organic extracts exhibited significant effects in several biotests. This may be relevant with respect to direct particle uptake via ingestion or respiration. Pollution patterns for heavy metals as well as for organic pollutants differed significantly from the pattern found in the Spittelwasser flood plain before the inundation, which is in contrast to the initial hypothesis of a possible transport of contaminated Spittelwasser sediments into residential areas. Interestingly, a correlation of chemical load and the overall biological effect could be shown. From the viewpoint of the precautionary principle, the identification of the compounds exerting toxic effects and of the respective pollutant sources would be desirable.     

Protective skin structures in shell-less marine gastropods

Skin and stomach epithelia of the four suborders of nudibranch gastropods (Mollusca, Opisthobranchia) are characterized by large intracellular ovoid disks, here called spindles. These spindles are an evolutionary novelty in the nudibranchs; in shell-less sacoglossan species they are missing. We here examined whether the distribution and occurrence of the spindles is consistent with the assumption of a protective role against discharging nematocysts of co-habiting and prey Cnidaria. Spindles were abundant in epidermal cells of regions exposed to nematocysts, such as the cerata, the lips, the edges of lamellate rhinophores, the surfaces of non-retractile gill-like organs, as well as in the stomach epithelium of eolid and dendronotacean species which feed on Cnidaria. While cells packed with spindles almost exclusively formed the epidermis of eolid and arminacean species, they were less numerous in the skin of dendronotacean and dorid species, where glandular cells predominated. The preponderance of either glandular or spindle cells suggests a dual complementary defense strategy, on the one side the production of mucus coats and aversive glandular secretions, on the other structural defensive devices that are cushion-like entities filled with inert grains.     

Toxizität von Aluminium

The concentration of solubilized aluminium in soils and waters increases due to environmental influences. To obtain information on the types of Al species occuring under these conditions, aluminium chloride solutions were prepared in a wide range of concentrations (10^?1–10^?5 mol·l^?1 Al) and basicity (OH/Al=0,5–2,5), respectively, and then structurally characterized using the ferron method. For the freshly prepared solutions, a decrease in the portion of monomeric Al species is observed, with an increasing OH/Al-ratio; the formation of polymeric cations decreases to lower OH/Al-ratios with diminishing concentration. The portion of tridecameric cations (Al₁₃) decreases with diminishing concentration, but so called transition polymers occur in these solutions. The transition polymers are instable under ageing; by inreasing the ageing time, a disproportion of these cations into monomeric and polymeric species can be observed. At extremly low Al concentrations (10^?5 mol·l^?1 Al), a condensation of the transition polymers into polymeric species occurs, after only a short ageing. The influence of admixtures of Mg²⁺-and Ca²⁺-ions, respectively, on the specification of the Al cations are only observed after longer ageing times; in this case, the formation of polymeric Al species is forced. The polymeric Al species therefore, seem to be especially preferred alongside the monomeric ones under biologically relevant concentrations.     

Fernmeßverfahren

The combination of remote sensing methods like Doppler lidar and FTIR allows remote determination of mass fluxes of gases. Doppler lidar measures the three-dimensional wind vector in the vicinity of diffuse sources, or the velocity of air in a chimney plume if an industrial complex is monitored. FTIR is a multicomponent remote sensing method for gas concentrations. The Fourier transformation of an interferogram of a Michelson interferometer within a FTIR system converts the recorded intensity (function of optical path length) to a spectral signal (function of wavenumber). Both information, velocity and concentration, give the mass fluxes of the tracer (gas). A first test was performed at Munich-Nord power station with FTIR and cw-Doppler lidar. Fluxes of CO₂, CO, NO, and HCl were determined. The results are in good agreement with the fluxes measured byin situ instruments of the power station. The method can be used to control industrial complexes from an outside observation site.     

Mineralölkohlenwasserstoffe im Boden bei der Sanierung von Altlasten

Various analyses and evaluative procedures are used to provide evidence of success using remediation procedures. Because of the lack of standardized procedures for soil assessment, general practice has unfortunately propagated the use of DIN standards for determining the level of similar parameters in water as well as for other heterogeneous matrices (e.g. in soil). A precise auditing of quality, however, has not been possible with this method, this procedure has even put the success of such a remediation into question. This article describes the problems of determining mineral hydrocarbon concentrations on soil as well as portraying the remediation of oil damages which has occurred on a site of a former waste oil redestillation facility [1, 2]. This procedure has been proved in practice and serves as a model because an adequately defined, standardized method (DIN standard) is lacking.     

Einsatz der Hasse-Diagrammtechnik zur vergleichenden Datenanalyse von Biomarkerantworten und ökotoxikologischen Tests

Ecotoxicological investigations focus on biological systems and their response to chemically induced stress. Experimental techniques are much more developed than deterministic dynamic modelling. In this methodological contribution a technique is presented, based on lattice theory. This technique, also calledHasse diagram technique, allows data analysis with respect to comparative evaluation. Hasse diagrams are used

? to suggest a possible measure of microbial diversity,

? to analyze dependencies between phospholipid fatty acids and simple geochemical parameters on an ordinal scale and

? to visualise complex results of interactions of humic substances with xenobiotics.