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Effects of the aquatic herbicide 2,4-D on the ecology of experimental ponds
1980
Boyle, T.P. (Columbia Nat. Fish Res.-Lab., US Fish Wildlife Serv., Route 1, Columbia, Missouri 65201 (USA))
Biochemical indicators of subsurface pollution
1980
Dermer, Otis C. (Otis Clifford) | Curtis, Vivian S. | Leach, Franklin R.
[Pesticides of major effect [pollution]]
1980
Tapia Z, R. (Universidad de Chile, Santiago. Facultad de Ciencias Quimicas)
[Water and vegetable contamination by heavy chemical elements]
1980
Nova S, A.R.
[Crisis of the environment and the future of human being [pollution]]
1980
Capurro S, L.F. (Universidad de Chile, Santiago. Facultad de Ciencias Veterinarias)
[Policy and administration of the enviromment in Chile]
1980
Katz, R.
[General aspects of air pollution and its effect in agriculture]
1980
Silo A, C. (Instituto de Salud Publica, Santiago (Chile))
Microbiological aspects of pollution control
1980
Dart, R. K. | Stretton, R. J.
Concentrations of heavy metals in forty sewage sludges in England
1980
Sterritt, R.M. | Lester, J.N. (Imperial College of Science and Technology, London (UK). Dept. of Civil Engineering, Public Health Engineering Lab.)
Abstract. Samples of forty sewage sludges taken in England during 1979 were analysed for ten heavy metals using a rapid flameless atomic absorption spectroscopic technique. For all metals the mean concentrations were influenced by a small number of sludges containing exceptionally high concentrations. Typically, the concentration ranges showed approximately a 100-fold spread. Calculations based on U.K. guidelines for limiting the addition of toxic metals in sludge to agricultural soils indicated that application rates would theoretically be limited for more than 75% of the sludges by the concentrations of Zn, Cu and Ni, expressed additively as the Zn equivalent. Calculations of the theoretical maximum quantities of sludges which could be applied to land on an annual basis suggested that a significant proportion of the sludges would be unsuitable for application to agricultural land at rates of more than 2 t ha('-1) yr('-1).
Afficher plus [+] Moins [-]Kepone effects on larval development of mud-crab and blue-crab
1980
Bookhout, C.G. (Duke Univ., Durham NC (USA). Dept. of Zoology) | Costlow, J.D. | Monroe, R.
Laboratory experiments were conducted to determine the effects of Kepone on the larval development of the mud-crab, Rhithropanopeus harrisii, and the commercial blue-crab, Callinectes sapidus, from the time of hatching until the 1st crab stage was reached. Differential survival of R. harrisii from hatching to 1st crab stage occurred in a range of 35 to 125 ppb Kepone, whereas differential survival of C. sapidus over the same period of development occurred in a range of 0.1 to 1.0 ppb. Statistical analysis indicated that, for every 10 ppb Kepone added, duration from hatching to 1st crab stage of R. harrisii was increased by 0.391+/-0.043 days; whereas for each increase of 0.1 ppb, the duration from hatching to 1st crab stage of C. sapidus is prolonged by 0.38+/-0.10 days. The 1st and 2nd zoeal stages of R. harrisii were the most sensitive developmental stages to Kepone, but the 1st zoeal stage of C. sapidus was not sensitive, statistically, to any concentration of Kepone tested. In zoeal stages II, III and IV, there were significant increases in mortality of C. sapidus over the previous stage in all media tested.
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