Swart, J (1985) De zuurstofhuishouding boven een mosselperceel. Master's Thesis / Essay, Biology.
|
Text
Biol_Ma_1985_JSwart.CV.pdf - Published Version Download (1MB) | Preview |
Abstract
This research project has been carried out at the Department of Biology of the University of Groningen in Co-operation with the Delta Department of Rijkswaterstaat of the Netherlands. In 1986 the building of the storm surge barrier (SSB) in the Oosterscheldt estuary will be finished. It will be used for protecting the coastal area against floods. It may be considered to use the barrier in case of an oil catastrophe at the North Sea or as a means to prevent the tidal movement for a while for building hydraulic constructions. In that case there will exist a situation of a closed, salt lake with only wind-driven currents. It is conceivable that this will take place at quiet weather circumstances. In periods with very low wind velocities the oxygen concentration in the water above a mussel bank may become low because of a long residence time of the water and because of a great oxygen need of the mussels. The purpose of this project was to investigate such a situation. This has been done by constructing a model with the help of data from literature and verbal information from various scientific workers. In chapter 2 the model is described. One may conceive the model as a train of columns of water above a mussel bank. In each column a number of processes are determining the oxygen concentration photosynthesis, mineralization, respiration,aeration by wind etc. These processes are described in chapter 3. Turbulence has been paid special attention in this chapter because of the assumption that the columns of water are well-mixed at any wind velocity. It turns out that this assumption can be accepted when the depth of the column is less then 2.60 m. This is actually the case with examined mussel banks. In chapter 4, the model has been compared with the results of an experiment of the Rijks Instituut voor Natuurbeheer on the island of Texel. It appeared that the simulation results were in good agreement with the experimental results. Some simulation has been done for the Oosterscheldt situation. These are described in chapter 5. It appeared that at low current velocities (less than 0.5 cm/sec) the concentration can become low: 2 to 3 g/m3 in August and 1 to 2 g/m3 in November. A reduction or increase of the temperature resulted in a increase, respectively a reduction of 0.5 g/m3. The influence of the depth appeared to be an acceleration of the reduction of the oxygen concentration. It is argued (chapter 6) that when the barrier is used, one has to make allowance for the results of this project: the use of the barrier at low current velocities, high temperatures and low water levels, the oxygen concentration can become very low. Perhaps this is possible in the case of building a hydraulic construction if a good weather forecasting is provided, but threatening oil disasters, unfortunately, cannot be predicted.
| Item Type: | Thesis (Master's Thesis / Essay) |
|---|---|
| Degree programme: | Biology |
| Thesis type: | Master's Thesis / Essay |
| Language: | Dutch |
| Date Deposited: | 15 Feb 2018 07:48 |
| Last Modified: | 15 Feb 2018 07:48 |
| URI: | https://fse.studenttheses.ub.rug.nl/id/eprint/10234 |
Actions (login required)
 |
View Item |