Tukkama

Kohler Verlag, 2002

7. SUMMARY Side effects of nitrification inhibitors DMPP, ClMPP and DCD on microbial „non-target“ processes and their ecological assesment in soils. In model experiments with soils the side effects and ecological assessments of three nitrification inhibitors (DMPP, ClMPP and DCD) was studied under laboratory conditions. All model experiments were conducted under standard laboratory conditions. The quantitative determination of dehydrogenase activity (DHA) and microbial iron reduction were carried out photometrically and dimethylsulfoxide reduction (DRA), denitrification and nitrogenase activity gaschromatographically. In order to determine if these three nitrification inhibitors have side effects on microbial „non-target „ process in soil and its ecological assessment, some standard methods were used to evaluate and characterize several microbial activities on loamy clay (Weilburger-Grenze, Giessen), clay loamy (Weihenstephan, München) and sandy soils (Limburgerhof, BASF). Nitrification inhibitors (DMPP, ClMPP and DCD) were applied directly to the soil at recommended field rate (0,36 µg , 0,25 µg and 10 µg g-1 dwt soil), as well as in 5, 10, 25, 50, 100, 250, 500 and 1000 times concentrations, respectively. The response of microorganisms were measured by various methods, such as : dehydrogenase activity, dimethylsulfoxide reduction, denitrification, microbial Fe(III) reduction, nitrogenase activity and nitrification. Subsequently, in laboratory using the same soils, DHA, DRA, microbial iron reduction, denitrification, nitrogenase activity, and nitrification were studied under controlled conditions according to standard tests. Chemical and physical soil parameters were analysed simultaneously. The effects of these three nitrification inhibitors are derived according to dose response curve in order to characterize ecological assessment in test soils. The resulting dose-response relationships ought to reveal to what degree the classical Sigmoid-shaped curve is valid even for heterogeneous populations. From the results it may be concluded that 1) There are no disadvantages of side effect of this nitrification inhibitors on microbial activity in soils which only use in recommended rate. 2) These three nitrification inhibitors (DMPP, ClMPP and DCD) at recommended rate have no side effect on microbial „non-target“ processes in soils, respectively, if any, only in very high concentration or 100 times of practical Dosage (36µg DMPP g-1 dwt soil, 25 µg ClMPP g-1 dwt soil and 1000 µg DCD g-1 dwt soil). According to statistical dose response curve showed that there is no significance effect (NOEL) on non target Process in soils when 63 µg DMPP, 34 µg ClMPP and 1707 µg DCD g-1 dwt soil were applied. These inhibitions depend on Parameter specificly. 3) Dose-Response-Relationship between nitrification inhibitors and microbial activities depend on soil types and properties. Microbial activity in loamy soils is higher than in clay soils or in sandy soils and these nitrification inhibitors are most effective in sandy soils. 4) According to NOEL, ED10-, ED50- and ED90-Value, it will be concluded that sensitivity of microbial denitrification > dimethylsulfoxid-reduction > dehydrogenase activity > microbial iron reduction > nitrogenase activity to nitrification inhibitors that applied. 5) The influence of ClMPP is more effective than DMPP and DCD on microbial non-target process in soil. Further research should included the quantification of degradation kinetics of these inhibitors in different soils and in different pure cultures of microorganisms that participated in specific microbial „non target“ process. This would help to confirm that the breakdown of these molecule and their effect in microbial metabolisms and warrant further study.

Mit dieser Passage eröffnet Peter Handke seine "Publikumsbeschimpfung", ein Stück, das als erstes behauptet, gar kein Theaterstück zu sein. Und doch stehen vier Personen auf der Bühne, die in den Zuschauerraum hineinsprechen. Es sind "Sprecher", vermerkt der Dramatiker in den "Regeln für die Schauspieler", die er dem Stück vorausschickt. Es war das erste Sprechstück des damals erst 23-jährigen Jurastudenten, uraufgeführt im Juni 1966 unter der Regie von Claus Peymann in Frankfurt am Main. Und es wurde eine Revolution. Handke führte das konventionelle Theater ad absurdum. Bühnenbild, Kostüm, ausgefeilte Beleuchtungalles Fehlanzeige. Nur Theater, das auf die Wirkung von Sprache reduziert war: ein reines Sprechstück. Um die Zuschauer/innen vor dem Beginn der Aufführung in der Sicherheit zu wiegen, dass alles wie gewohnt ablaufen würde, wurden Tonbänder hinter dem geschlossenen Vorhang abgespielt, auf denen man das Verrücken von Requisiten hörte und das Flüstern von Schauspielern/innen. Gegen das "epische Theater"

Kunstbulletin 6, 2022

Das sakralisierende Pathos, das um Antiken aufgebaut wird», sagt Antiquitätenhändler Jean David Cahn, «ist mir ein Graus» Darin trifft er sich mit der in Paris lebenden Bildhauerin Katinka Bock (*1976, Frankfurt/M): «lch hatte grosse Sorge», gibt sie am Telefon preis, «jetzt mit einem Werk-Pathos konfrontiert zu sein, das ich in meiner Arbeit immer vermeide» Die Sorge ist unbegründet.