University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal

Logo BOKU Resarch Portal

Gewählte Master / Diploma Thesis:

Master / Diploma Thesis - Institut für Siedlungswasserbau, Industriewasserwirtschaft und Gewässerschutz (SIG), BOKU-Universität für Bodenkultur, pp 111. UB BOKU obvsg

Data Source: ZID Abstracts
Natural lakes are “ageing” over time. This process is due to sedimentation and nutrient enrichment in the sediment. The nutrient enrichment generates an excessive growth of plants or algae. In the case of DOK III the problem is a massive plant growth which allows only a limited use of the DOK III for swimming, fishing or boating. The aim of this work is to collect information about the nitrogen and phosphorus loads in different media, the phosphorus input and output in order to calculate a phosphorus balance, as base for the assessment of remediation measures. The length of DOK III is 2,4 km, the width is 30 m and it is up to 3 m deep. It is groundwater-fed an there is a water discharge from the company Ardo, which has a consensus of up to 245 l/s of unpolluted cooling water. Water, sediment and plants were sampled at DOK III and the phosphorus concentration was analysed in the labor, and compared with previous data. Residents were asked to reply to a questionnaire and groundwater-data were explored from public databases. When the nutrient load and the nutritional balance was established it was determined that about 99 % of the limiting nutrient phosphorus is stored in the sediment. The main nutrient sources are the groundwater, the fertilisation by residents and the discharge by company Ardo. Since the phosphorus is already stored in the sediment, removal from the water body is not necessary. The final recommendation combines the removal of the sediment and of high-growing plants and the subsequent replantation of new low-growing plants as otherwise algae will settle in the DOK III. The second option would be to preserve the plants and organize a mowing management.

Beurteilende(r): Fürhacker Maria
1.Mitwirkender: Moog Otto

© BOKU Wien Imprint