TNT in Komposten und Flüssigkultur

The formation of aromatic amines was investigated using a summarized test (NEDA-test) during the composting of 2,4,6-trinitrotoluene (TNT) contaminated soil. In this test, the aromatic amines were diazolated and then coupled to N-1-Naphthyl-ethylenediamine-dihydrochloride (NEDA) to yield an azo dye which can be monitored photometrically. The test was calibrated for known TNT-metabolites with an active amine-group. Liquid samples from composting- and liquid-culture-experiments were analyzed by HPLC for these known metabolites. Moreover, the samples were monitored by the NEDA-test and the expected extinction of the TNT-metabolites found with amine function were extrapolated with the help of calibration curves. It was shown that substantial differences are obvious between the monitored and extrapolated values. After separation into polar and non-polar aromatic amines, it became clear that these differences are made by the polar aromatic amines. Polar aromatic amines, which are not detectable by presently available analytical tests, were generated during the composting of TNT-contaminated soils. Contaminated stagnant water, which was generated during anaerobization of a compost prephase, was treated aerobically for 70 days in a biofermenter. During this treatment TNT and its known metabolites were eliminated almost entirely. Simultaneously, the toxicity in the Lumis Tox-test decreased drastically. In striking contrast, the sum of aromatic amines decreased only to a minor extent. Moreover, the percentage of polar compounds from total amount of aromatic amines increased drastically from 48% to more than 95%. At present, the chemical identification of these polar compounds is still missing and is the object for further research.     

Räuber-induzierte Feindabwehr bei Protozoen

Die Abfassung dieses Beitrages wurde durch Professor Hermann Remmert angeregt, der am 23. 6.1994 verstarb. Der Aufsatz ist seinem Andenken gewidmet.     

Landscape protection as a tool for managing agricultural landscapes in Norway

Norwegian Protected Landscapes aim to preserve landscape character. As most of the agricultural land in Protected Landscapes is privately owned, the attitudes and behaviour of farmers are crucial in achieving this goal. We present results of a nationwide questionnaire to farmers who owned or managed farmland in Protected Landscapes. Thirty-eight percent of the respondents claimed that their farm business had been changed as a consequence of landscape protection. Niche products and alternative income possibilities, commonly forwarded as potential benefits of landscape protection status, had generally not been realised. Although we found that most farmers agreed on the importance of taking care of cultural landscapes, 76% felt that this was best done by using rather than protecting the landscape. The study revealed negative attitudes towards municipal authorities. A quarter of respondents were strongly against the establishment of new Protected Landscapes, even if they were compensated for economic losses. Based on results of the study we suggest that major improvements to the protection system could be made by improving communication between management authorities and farmers, and ensuring real involvement of farmers in making and carrying out management plans.