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Sensitivity of a marine amphipod to non-contaminant variables and to copper in the sediment [Gammarus locusta]
1995
Costa, F.O. (Universidad Nova de Lisboa (Portugal)) | Correia, A.D. | Costa, M.H.
Xenobiotic-inducible alkoxycoumarin and alkoxyresorufin dealkylases in higher plants
1995
Batard, Y. (Centre National de la Recherche Scientifique, Strasbourg (France). Institut de Biologie Moleculaire des Plantes, Departement d'Enzymologie Moleculaire et Cellulaire) | Zimmerlin, A. | Schalk, M. | Durst, F. | Werck Reichhart, D.
Nitrate reductase activity in aquatic plants as an indicator of ammoniacal nitrogen contamination
1995
Rolland, T. (Institut de Botanique, Strasbourg (France). Laboratoire de Botanique et d'Ecologie Vegetale) | Robach, F. | Tremolieres, M. | Dester, S.
Honeybee, animal sentinel of environment
1995
Fleche, C. (Centre National d'Etudes Veterinaires et Alimentaires, Biot (France). Laboratoire de Pathologie des Petits Ruminants et des Abeilles) | Zeggane, S. | Flamini, C. | Faucon, J.P.
Antioxidants as indicators of stress in Norway spruce needles
1995
Ribaric-Lasnik, C. (ERICO, Velenje (Slovenia)) | Batic, F. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.) | Grill, D. (Graz Univ. (Austria). Plant Physiology Inst.)
Among a variety of stress indicators for early identification of Norway spruce (Picea abies (L.) Karsten) decline the sulphur content, photosynthetic pigment content, activity of the enzyme peroxidase, watersoluble thiols and ascorbic acid in 4 age classes of 5 spruce needles were analysed. The 10 sampling sites were selected according to the degree of forest decline, sea level, distances from the Thermal Power Plant Sostanj and air pollution.
Afficher plus [+] Moins [-]Ectomycorrhizal response to environmental perturbation
1995
Afs, T. (Sheffield Univ. (United Kingdom). Animal and Plant Sciences Dept.)
The use of ectomycorrhizal fungi as possible indicators of ecosystem response to disturbance is discussed with emphasis on the analysis of individual species by direct observation of their mycorrhizas. Some examples of such studies are given. The possible role of fungal diversity and differential tolerance by individual species to pollutants are also discussed in relation to observed changes within ectomycorrhizal fungal communities.
Afficher plus [+] Moins [-]Evaluation of forest soil sampling methodology
1995
Kalan, P. | Simoncic, P. (Forestry Inst. of Slovenia, Ljubljana (Slovenia)) | Hudnik, V. (Chemistry Inst. of Slovenia, Ljubljana (Slovenia))
Forest soil was sampled on two different observation plots by following well described methodology. Sampling sites had been chosen in place with typical soil conditions for the observed forest site. To make sampling easier some natural forest site characteristics were considered. Mg, Zn and Cd were determined by atomic absorption spectroscopy in all samples. Results were statistically evaluated and different sources of variance were estimated. It was also estimated whether the number of samples was sufficient for our requirement for accuracy of analytical results.
Afficher plus [+] Moins [-]GIS-Applications for forest pollution problems - combination of models with GIS databases
1995
Lenz, R. | Stary, R. | Schaller, J. (Munich-Weihenstephan Technical Univ. (Germany). Chair for Landscape Ecology)
It is often difficult to predict how synergistic effects work and how dieback may be expected to spread through an area over time. On the other hand concepts and methods for compensation of acid deposition, melioration and restauration of acidified forest areas represent a major management problem. The following examples show how GIS may be used to find answers to these questions.
Afficher plus [+] Moins [-]Ten years of forest decline inventorying in Slovenia - an overview
1995
Kovac, M. | Kobler, A. | Ogulin, A. (Forestry Inst. of Slovenia, Ljubljana (Slovenia))
The article presents a state of art of forest decline inventories in Slovenia. The first part deals with methodological and technological aspects of forest health inventories, while the second one describes some hints and directions of further forest inventories development.
Afficher plus [+] Moins [-]Methodology survey of integral research of changes in forest ecosystems
1995
Littvay, T. | Krznar, A. (Forest Research Inst. Jastrebarsko, Zagreb (Croatia)) | Papes, D. (Zagreb Univ. (Croatia). Natural Sciences Fac.)
Research was carried out in EMFT, II-G-10 (common oak and common hornbeam zone) and in main EMFT-s on the karst (pubescent oak and oriental hornbeam, and holly oak zones) in which forest fuel loads were determined too. Soil and structure elements were sampled and measured, stand vitality and quality were measured and evaluated. Chemical and physical analyses of soil samples were performed. The samples of precipitation's and plant material were chemically analyzed. It contains the data of normal and changed forest conditions (first measurement 1969-1981, second measurement 1991-1993). In second measurement the research that deals with tree breeding and fructification was added to the project. The aim of this recently introduced research is to determine the dynamics of flowering and phenotype damage degree. Cytogenetic and some biochemical analyses were carried out with the aim of determining and establishing methodology of work. The data base was built up and data search programs were developed. The relations of ecological and structural stand elements for normal and changed stand conditions were determined. The results achieved are the basis for building up the diagnostic stand models and the evaluation model of ecological-environmental ecosystem value. The main purpose is to support decision making on different management levels.
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