The two-way feedback system in offshore sandwave fields : The interactions between the seabed and the benthic community 30 km offshore of Texel
Temmerman, Y. (2018). The two-way feedback system in offshore sandwave fields : The interactions between the seabed and the benthic community 30 km offshore of Texel
. Thesis. NIOZ Royal Institute for Sea Research: Yerseke. 32 pp.
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| Abstract |
More so than ever before, coastal seas are becoming ever more important, both economically and ecologically because they support a variety of offshore activities. Cumulatively, all of these anthropogenic activities have an effect on the environment, especially ones such as sand mining which directly impact the environment. When an area is subjected to sand mining, a large amount of sediment is extracted, which also removes the benthic organisms within. The extraction site then needs time to recover, which in the case of even shallow extractions can take at least 4-6 years. In cases of deeper extractions, the area may not fully recover even after 11 years. Therefore it is important to find more sustainable ways of sand mining, which requires a better understanding on the two-way feedback between the seabed and the benthic community. An offshore sandwave field located approximately 30 km from Texel was investigated. Sixteen stations were sampled over a transect orientated along a series of sandwaves; two of the three sample replicates were analysed in this study. The macrofauna samples were sorted and the specimens were identified to family level. With this information it was possible to see notable differences over the four parts of the sandwave. Firstly, the distribution of the benthic communities was different in each part. The families were quite consistent but the abundance and the number of taxa were distributed unevenly over the sandwave. The Loveniidae, Tellinidae and Phoronidae families were the three most dominant ones identified. Based on differences also observed in the sediment data, there appears to be some feedback between the seabed and the benthic macrofauna. Further analyses on these samples (i.e. species level identification) should be undertaken to determine the exact nature of this two-way feedback, which would help gain a better understanding of the importance of the benthos in these sandwave environments. |
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