| Autor: |
J. M. Suijlen, J. J. Buyse |
| Rok vydání: |
1994 |
| Předmět: |
|
| Zdroj: |
Limnology and Oceanography. 39:1411-1423 |
| ISSN: |
0024-3590 |
| DOI: |
10.4319/lo.1994.39.6.1411 |
| Popis: |
The dispersal of 0.13 kg of water-tracer rhodamine WT in the Loosdrecht lakes was surveyed during 19 months. Solid-phase extraction and liquid chromatography were used to measure the very low concentrations of rhodamine WT in the experiment. The detection limit was -2 x lo-l1 kg m-3. The photolysis constant of rhodamine WT was measured in a laboratory experiment. A numerical model for hindcasting the dilution of a photolytic tracer in the lake system was developed. Model results compare well with observations showing that rhodamine WT is well suited for tracer experiments on large time and space scales, provided that photolysis is taken into account. In densely populated and industrialized regions, those responsible for the conservation of the natural environment encounter various water-quality problems. These problems involve not only sudden contaminations of aquatic systems by industrial accidents but also more gradual deterioration (e.g. due to continuous releases of nutrients and toxic chemicals). Appropriate measures require knowledge of the transport mechanisms applying to both sudden and continuous releases of various chemical substances. Tracer experiments are a powerful tool for investigating these mechanisms and validating transport models (e.g. Carter 1974; Leibundgut 1982; Van Dam 1982). Because of the limitations of earlier fluorometric detection methods (e.g. imposed by high background fluorescence) and the strong dilution of tracers in the surface water, useful observation periods of fluorescent tracers have generally been restricted to a few days. Studies of |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Plný text