ПОЧВЕННАЯ ЭКОТОКСИКОЛОГИЯ ДЛЯ ЗАЩИТЫ ПОЧВ - НА ПРИМЕРЕ ЧЕШСКОЙ РЕСПУБЛИКИ Хофман Я.
SOIL ECOTOXICOLOGY FOR SOIL PROTECTION - EXAMPLE OF THE CZECH REPUBLIC Hofman Jakub Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Brno, Czech Republik. hofman@recetox.muni.cz Soil is the principal component of the terrestrial ecosystems and plays key role in primary production, decomposition process, humus formation, cycles of nutrients, energy and water, biodiversity maintenance, and it helps also in pollutants degradation. All these functions must be carefully protected for sustainable development. Unfortunately, there was extensive pedosphere exploitation in the last centuries. Degradation by pollution belongs to major threats to soils. The scientific basis for the soil protection against the chemical pollution is the soil ecotoxicology which studies the relationships between soil organisms and pollutants. Activities of the soil ecotoxicologists go from the development of bioassays applicable in routine praxis to the sophisticated research of complicated issues. The aim of this presentation is to acquaint the conference forum with the development and status quo of soil ecotoxicology role in soil protection in the Czech Republic. There are few emerging legislations in the Czech Republic which go along to EU development in this area including new test battery for wastes testing and for dredged sediments assessment. Applicability of batteries of bioassays was verified in two large projects which results will be briefly shown. Generally, the results of both projects proved that bioassays bring information not apparent from chemical analyses and must be included in legislation protecting soil quality. Very fresh issue has been addressed in two new projects: application of soil ecotoxicology methods for the bioindication of status of natural soils - fluvisols often seriously contaminated due to flooding despite used for crop production and forest soils which are not treated by any legislation in CR. Alongside with new applications of soil ecotoxicity bioassays, several interesting research topics have been investigated in the Czech Republic (e.g. ecotoxicity of priority and emerging persistent organic pollutants to soil organisms and bioavailability of POPs in soils). In summary, soil ecotoxicology did large step in past 15 years in CR, properly corresponding with current international trends. ПРОБЛЕМЫ ИСКУСТВЕННОЙ ПОЧВЫ И СТАНДАРТНОЙ ПОЧВЫ В ЭКОТОКСИКОЛОГИИ Хофман Я. PROBLEMS OF ARTIFICIAL SOIL AND REFERENCE SOIL IN ECOTOXICOLOGY Hofman Jakub Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Brno, Czech Republik. hofman@recetox.muni.cz Artificial soil is defined as a mixture of 70% fine quartz sand (50% particles 0.05-0.2 mm), 20% kaolin clay (kaolinite above 30%), and finely ground Sphagnum peat. The artificial soil was developed to achieve a standardized "soil-like" medium, which is less variable than natural soils and can be used to produce reproducible and comparable data and which is much more representative of natural soils than filter paper, agar or solutions. Despite the great idea, undoubtedly necessity, and usefulness of such a “reference material”, the frequent and widespread use of OECD artificial soil has revealed several problematic issues which must be seriously considered. One of these issues is that although the amount of compounds used for the artificial soil preparation is strictly defined, specific properties of the compounds are only briefly described and they probably vary among the producers and countries a lot. This could be the reason of high variability of the toxicity results between laboratories, though standardized procedures and reference substances are used. The question arises: Is the OECD artificial soil really a standardized reference material omitting the influences of varying soil properties or is there still significant variability present which influences toxicity results and risk assessment and which should be addressed and then reduced? Another important issue is ability of artificial soil to predict the effects, exposures and risks of soil organisms in real soils.
The toxic effects and risks of the test chemicals are strongly dependant on their behaviour, adsorption and bioavailability in soil which are influenced by the soil properties. Properties of artificial soil apparently differ from many natural soils and extrapolation approach is necessary. This contribution shows the results of our studies which focused on a) addressing the variability of 25 artificial soils prepared in different laboratories in Europe and Canada, and b) comparison of bioavailability and extractability of pesrsistent organic pollutants artificial and natural soils. There were found large differences between the artificial soils prepared in various labs and it is still an unanswered question, to which degree this may influence the toxicity results in the framework of ecological risk assessment. Artificial soil also differed significantly from natural soils and, unfortunately, known parameters like TOC may not be used to extrapolate the results. All these results imply that artificial soils should be used cautiously and possibly its use in soil ecotoxicology should be completely verified. СРАВНЕНИЕ ЧУВСТВИТЕЛЬНОСТИ К МОДЕЛЬНОМУ ТОКСИКАНТУ РАЗЛИЧНЫХ СПЕКТРАЛЬНЫХ ХАРАКТЕРИСТИК КУЛЬТУРЫ МИКРОВОДОРОСЛЕЙ SCENEDESMUS QUADRICAUDA Хунджуа Д.А.1, Попутникова Т.О.1, Гладкова М.М.1, Пукальчик М.А.1, Терехова В.А.1,2, Маторин Д.Н.1, Харчева А.В.1, Пацаева С.В.1 1 Московский государственный университет имени М.В. Ломоносова, Москва, Россия. dasha.ok@list.ru 2 Институт проблем экологии и эволюции им. А.Н. Северцова РАН, Москва, Россия COMPARISON OF SENSITIVITY TO MODEL TOXICANT FOR DIFFERENT SPECTRAL CHARACTERISTICS OF MICROALGAE CULTURE SCENEDESMUS QUADRICAUDA Khundzhua D.A., Poputnikova T.O, Gladkova M.M., Pukalchik М.А., Terekhova V.A., Matorin D.N., Kharcheva A.V., Patsaeva S.V. Биотестирование широко используют в современной природоохранной практике. Помимо задач экологической оценки природных сред, биотесты применяются для экспериментального установления класса опасности отходов производства и потребления. В качестве стандартных тест-организмов чаще всего используют альгологические чистые культуры одноклеточных зеленых водорослей Scenedesmus quadricauda и Chlorella vulgaris. Традиционно влияние вещества на культуру Scenedesmus оценивают по показателям изменения численности клеток за 72 часа экспозиции. Несомненный интерес представляют экспресс-методы альготестирования, к которым можно отнести различные спектральные алгоритмы. Однако сведения о сопоставимости результатов экспериментов, полученных с использованием различных приборов и методов обработки данных, пока недостаточны. В работе сравниваются различные методы регистрации токсического действия модельного токсиканта дихромата калия на S. quadricauda. Жизнеспособность водорослей оценивали следующими способами: (1) по изменению прироста численности популяции клеток, подсчитанных при микроскопировании суспензии в камере Горяева, (2) по измерению оптической плотности суспензии клеток с помощью установки ИПТ-02 («Энерголаб», Россия), (3) по измерению параметров флуоресценции Fo - фоновой быстрой флуоресценции адаптированных в темноте клеток и Y - эффективного квантового выхода на свету с помощью прибора ToxyPam (Walz, Germany), (4) по поглощению хлорофилла Dchl, рассчитанному из спектров оптической плотности (измерение на спектрофотометре Unico, США), с вычитанием фона, обусловленного рассеянием света, (5) по интегральной интенсивности флуоресценции хлорофилла F475, возбуждаемой светом с длиной волны 475 нм (флуориметр Solar CM2203, Беларусь). Установлено, что показатели Fo, Y, Dchl и F475 с высокой достоверностью коррелируют с показателем прямого счета клеток.