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Modification of chronic sulphur dioxide injury to Lolium perenne L. by different sulphur and nitrogen nutrient treatments
1980
Ayazloo, M. (Dep. of Bot., Imperical Coll. Field Sta., Silwood Park, Ascot, Berks SL5 7PY (UK)) | Bell, J.N.B. | Garsed, S.G.
[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)
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)
[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.
Acid rain: threshold of leaf damage in eight plant species from a Southern Appalachian forest succession
1980
Haines, B. (Georgia Univ. Athens (USA). Dept. of Botany) | Stefani, M. | Hendrix, F.
Eight plant species were subjected to artificial acid rains of pH 2.5, 2.0, 1.5, 1.0 and 0.5 in order to determine the threshold for and symptoms of damage. The plants were Erechtites, Robinia, Pinus, Quercus, Carya, Liriodendron, Acer and Cornus from the Coweeta Hydrologic Laboratory near Franklin, North Carolina. Droplets of pH 2.0 produced brown necrotic spots on all species except Pinus while droplets of pH 1.0 produced necroses on leaves of all species examined. The size of necrotic spots increased with increasing acidity. Comparison of these results with the literature suggests that developing leaves are more easily damaged than are the mature leaves used in this study. The volume weighted average rainfall pH for Coweeta is 4.6 with observations ranging from 3.2 to 5.9. Results of this study suggest that a 10-fold increase in acidity from pH 3.2 to 2.2 in a single spring or summer storm could bring damage or death to mature leaves of dominant flowering plants in the Southern Appalachians.
Mostrar más [+] Menos [-]Leaching of the herbicide bromacil after application on railroads in the Netherlands
1980
Smelt, J.H. (Laboratorium voor Insekticidenonderzoek, Wageningen (Netherlands))
The herbicide bromacil was applied annually or once in 2 yr to a railway track on a sand bed. Once a year, in the Spring, just before a possible next application, samples were taken from various depths down to at least 80 cm for residue-analysis by gas chromatography. The procedure for extraction was adapted in order to eliminate interfering substances originating from the dark top layer of the soil. Bromacil contents were always highest in the 10 to 20 cm layer. Within the first 2 yr of the experiments the compound penetrated down to depths around 100 cm. Calculations showed that deeper penetration of bromacil was probable. On account of the low conversion rate of the herbicide it seems possible that a part of the bromacil dosage leached to the groundwater later on
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