 | Water temperatures and the ecological reserve |
| Expanded Title: | A large body of scientific literature has highlighted the importance of water temperature as a primary abiotic driver of lotic systems, particularly those regulated by impondments. In South Africa the river flow regulation is mainly based on reserve determinations. In literature there are no clear guidelines on how to incoporate thermal aspects into the management of rivers and their integrity. This is viewed as a huge gap, as impact of water temperature is quoted to be as important as hydrological drivers of the systems. The main aim of this study was to develop test and monitor temperature threshold methods and procedures (using testedindicator biota - selected macoinvertebrates of the Western and Southern Cape) to establish temperature thresholds and their incoporation into the reserve determinations, with a view to try and close the knowledge gap in sustainable ecosystem development, as well as monitoring the trends of climate chan,ge temperature changes over time.
A total of 92 sites in rivers in the Eastern and Western Cape provinces were selected for installation of water temperature loggers. Sites were selected to cover a range of ecoregions and river longitudinal zones (geomorphological classes). An additional 50 sites from collaborative projects were also used. Hourly water temperature data were collected over a period of two years using Hobo UTB1-001 TidBit V2 loggers. Air temperature and relative humidity data were collected at 47 sites to facilitate linking water temperatures to air temperatures for water temperature modelling purposes.
The body of research in this project represents a considerable advancement in understanding thermal patterns in South African rivers, and how biota (individual species and aquatic macroinvertebrate communities) respond to thermal variability and stress. This fundamental research has a great potential and impact if implemented through the monitoring of temperature thresholds through the ecological reserve. |
| Date Published: | 10/11/2012 |
| Document Type: | Research Report |
| Document Subjects: | Ecosystem - Biodiversity protection, Ecosystem - Invertebrates |
| Document Format: | Report |
| Document File Type: | pdf |
| Research Report Type: | Standard |
| WRC Report No: | 1799/1/12 |
| ISBN No: | 978-1-4312-0300-0 |
| Authors: | Dallas H; Rivers-moore N |
| Project No: | K5/1799 |
| Originator: | WRC |
| Organizations: | The Freshwater Consulting Group |
| Document Size: | 3 043 KB |
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