Untersuchungen zur Aufnahme von HCB und Pyren durch den KompostwurmEisenia fetida und ausgewählte Regenwurmwildarten

The main issues of the studies described were the validation of a test design for the assessment of the bioaccumulation potential of environmental pollutants and the applicability ofEisenia fetida as a model-organism and artificial soil (OECD) as a standard test substrate. The test organisms used wereE. fetida of our own breeding stock andAllolobophora caliginosa, Allolobophora chlorotica, Allolobophora longa and Lumbricus rubellus sampled from a field site. Test soils used were the artificial soil (OECD) and a BBA field soil. Soils were each contaminated with 10 mg HCB and Pyrene per soil dry-weight. Within the test period of 4 weeks, samples were taken weekly for residue analysis in the worms and soils. Bioaccumulation factors (AF) calculated forE. fetida and the free-living species were in the range of 10–17 (HCB) and 0.9–1.7 (Pyrene) depending on the soil used. By re-calculation of the concentrations in soil to concentrations in soil water, the resulting bioconcentration factors are compared with published BCF values determined from QSAR’s of other worm species and fresh water fish. It could be concluded that the existing earthworm tests (OECD 1984, ISO 1998) represent an appropriate design for testing the bioconcentration potential of chemicals in soil.     

Economists' opinions on environmental policy instruments: Analysis of a survey

Incentive instruments (effluent charges) are theoretically expected to be preferred to direct regulations (individual emission ceilings) by university-employed, theoretically inclined politically right-wing, professional economists living in a market-oriented country, ceteris paribus. Public sector employed, politically left-wing, professional economists living in a country with a long tradition of government involvement prefer the regulatory approach, ceteris paribus. These theoretical hypotheses tend to be supported by a bivariate probit analysis based on a survey of more than 1400 economists in five countries.     

Temperature and salinity adaptation in the purple shore crab Hemigrapsus nudus: An in vitro metabolic flux study with excised gills

The effects of temperature and salinity acclimation on intermediary metabolism in excised gill homogenates from Hemigrapsus nudus were examined. In general, a decrease in salinity was followed by an increase in the oxidation of the substrates glucose-1-¹⁴C, acetate-1-¹⁴C and glycine-¹⁴C to ¹⁴CO₂. Also, there was an increase in amino acid incorporation into the protein fraction. Both of these metabolic parameters were differentially temperature-sensitive. An enzymic model which may explain the increase in respiration rate observed in several intertidal invertebrates meeting an hypo-osmotic stress is proposed, using data from these experiments and also from the literature.     

Characterization of an Fe4S4 (‘P’) cluster containing species from the nitrogenase MoFe protein ofAzotobacter vinelandii

Dedicated to Prof. E. Fluck on the occasion of his 60^th birthday