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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.
[General aspects of air pollution and its effect in agriculture]
1980
Silo A, C. (Instituto de Salud Publica, Santiago (Chile))
[Policy and administration of the enviromment in Chile]
1980
Katz, R.
[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)
[Pesticides of major effect [pollution]]
1980
Tapia Z, R. (Universidad de Chile, Santiago. Facultad de Ciencias Quimicas)
Microbiological aspects of pollution control
1980
Dart, R. K. | Stretton, R. J.
Ozone and chlorine dioxide technology for disinfection of drinking water
1980
Katz, J. (Janet)
The absorption and evaporation of tritiated water vapor by soil and grassland
1980
Garland, J.A. (E. and M.S. Division AERE, Harwell, Oxon. (UK))
The absorption and loss of tritiated water (HTO) vapor at bare soil and grass surfaces were studied in laboratory and field experiments. The exchange involves turbulent mixing in the air and diffusion within the soil. In short exposures it was found that uptake by moist soil was controlled by atmospheric mixing and was described by an exchange velocity of about 1 cm/s('-1). The exchange velocity was a little smaller for air-dried soil and grass surfaces. For exposure times exceeding a few minutes re-evaporation reduced the rate of net uptake, but the total amount deposited continued to increase as the HTO diffused deeper into the surface. The diffusion coefficient for HTO in soil was investigated in the laboratory and a simple equation was derived to predict the effective diffusion coefficient. Tritiated water, absorbed during a brief exposure, evaporated during several weeks. Its behaviour was described by the diffusion equation, but unexplained discrepancies were found in apparent diffusion coefficients in field conditions. Rain washed the activity into the soil and impeded evaporation. Most of the HTO vapor interacts with the surface within two or three days following a low level release. The effect of the surface exchange on the distribution of dose following a release of HTO vapor may be large, but will depend on the weather over a period of weeks and is difficult to foresee
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