Affiner votre recherche
Résultats 1-10 de 20
Biological variation in sensitivity to N-heterocyclic PAHs; effects of acridine on seven species of micro-algae
1997
Dijkman, N.A. | Vlaardingen, P.L.A. van | Admiraal, W.A. (Amsterdam Research Institute for Substances in Ecosystems (ARISE), University of Amsterdam, Department of Aquatic Exotoxicology, Kruislaan 320, 1098 SM, Amsterdam (Netherlands))
Effects of the insect growth regulator (S)-methoprene on survival and reproduction of the freshwater cladoceran Moina macrocopa
1997
Chu, K.H. | Wong, C.K. | Chiu, K.C. (Department of Biology and The Centre for Environmental Studies, The Chinese University of Hong Kong, Shatin, NT (Hong Kong))
Bioaccumulation profiles of polychlorinated biphenyls including coplanar congeners and possible toxicological implications in Baikal seal (Phoca sibirica)
1997
Nakata, H. | Tanabe, S. | Tatsukawa, R. | Amano, M. | Miyazaki, N. | Petrov, E.A. (Department of Life Environment Conservation, Ehime University, Tarumi 3-5-7, Matsuyama 790 (Japan))
Clarification of effects of DDE on shell thickness, size, mass, and shape of avian eggs
1997
Blus, L.J. | Wiemeyer, S.N. | Bunck, C.M. (National Biological Service, Forest and Rangeland Ecosystem Science Center, Northwest Research Station, 3080 SE Clearwater Drive, Corvallis, OR 97333 (USA))
Development of zinc bioavailability and toxicity for the springtail Folsomia candida in an experimentally contaminated field plot
1997
Smit, C.E. | Beelen, P. van | Gestel, C.A.M. van (Department of Ecology and Ecotoxicology, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands))
Toxicity of acid-sulphate soil leachate and aluminium to the embryos and larvae of Australian bass (Macquaria novemaculeata) in estuarine water
1997
Hyne, R.V. | Wilson, S.P. (Ecotoxicology Section, Environment Protection Authority NSW, at EPA/UTS Centre for Ecotoxicology, University of Technology - Sydney, Westbourne St., Gore Hill, NSW 2065 (Australia))
Diagnosis of boron, fluorine, lead, nickel and zinc toxicity in citrus plantations in villarreal, spain
1997
Aucejo, Antonio | Ferrer, José | Gabaldón, Carmen | Marzal, Paula | Seco, Aurora
In the late 1980s, citrus plantations in the area of Villarreal (Spain) showed injuries similar to those previously reported for boron and fluorine toxicity. The area was affected by the disposal of industrial wastewater, mainly from ceramic industries. Conjunctive uses of surface water, groundwater and wastewater for irrigation had taken place. A survey was conducted at 25 orchards to assess leaves and soil for their boron, fluorine, lead, nickel and zinc contents. Wastewater and groundwater were also analyzed to corroborate the presence of these pollutants. The results showed that both boron and fluorine contents were greater than those reported as excess at the most part of the orchards included in the study. Heavy metals toxicity effects were not confirmed. Boron pollution was attributed to industrial wastewater spills and fluorine contamination from atmospheric pollution.
Afficher plus [+] Moins [-]Ecological effects of combined organic or inorganic pollution on soil microbial activities
1997
Gong, Ping | Sun, Tie-Heng | Beudert, Günter | Hahn, H. H. (Hermann H.)
Combined effects of organic or inorganic pollutants on soil microbial activities were investigated in field plots grown with four types of covering plants. It was derived from this study that combined effects were dependent not only on the type and dose of pollutants, addition of soda lime, plant type and season variation, but also on test parameters. When jointly added, higher doses of Cd, Cu, Pb, Zn and As caused significant inhibition. Addition of soda lime could even enhance inhibition. Joint effects of phenanthrene, MET (active ingredient: paclobutrazol) and 1,2,4-trichlorobenzene were not significant, and may be covered by other biotic or abiotic factors. Compared with other two parameters (respiration and microbial biomass), dehydrogenase activity appeared to be more sensitive for evaluating the toxicity of anthropogenic pollutants in soil. Soil samples collected in summer often had higher microbial activities than those in fall. The microbial activity in soil decreased with covering vegetation in the order alfalfa > pine > poplar and maize, albeit some exceptions were observed.
Afficher plus [+] Moins [-]The seasonal changes of keratinolytic fungi in sediments of Catalonian Rivers (Spain)
1997
Ulfig, K. | Łukasik, W. | Guarro, J. | Cano, J. | Gené Badía, Joan | Vidal, P. | Figueras, M. J.
The Catalonian river sediments were found to be rich in keratinolytic fungi. The keratinolytic fungal populations showed clear seasonal changes in the river sediments. The main factors ‘regulating’ these populations in such habitat were temperature, dissolved oxygen concentration, pH, ammonium, nitrates, total fungal number, BOD₅, water poisons (cyanides, detergents, phenols), salinity and, presumably, strong insolation associated with low water levels. The last was probably of special importance in the deterioration of the fungal populations in the spring/summer season. A toxic effect on keratinolytic fungi in sediments was observed.Chrysosporium keratinophilum was found to be most resistant to industrial contaminants and salinity. Therefore, this species could be used as an indicator of water pollution.
Afficher plus [+] Moins [-]Leachability and immobilisation of beryllium from solid waste (red-mud) generated in processing beryl
1997
BHAT, P. N. | PILLAI, K. C.
In view of the toxic nature of Beryllium and its compounds the disposal of waste materials containing beryllium needs prior evaluation. The present study was undertaken to obtain information on the leachability and immobilisation of beryllium from solid waste red-mud generated in processing Beryl at the Beryllium Metal Plant at Vashi, New Bombay. The studies showed that 62% of the total beryllium in red-mud can be extracted by water by repeated leaching over a period of 445 d. The mixing of the waste material with cement and casting into cement blocks reduced the leachability of beryllium to 0.11% which got further reduced to 0.02% by thermal curing of cement blocks.
Afficher plus [+] Moins [-]