Quantitative sampling of benthic organisms by diving on the Swedish west coast
In: Helgoländer Wissenschaftliche Meeresuntersuchungen. Biologische Anstalt Helgoland: Hamburg. ISSN 0017-9957, more
Also appears in:Kinne, O.; Aurich, H. (Ed.) (1967). Vorträge und Diskussionen. Erstes Europäisches Symposion über Meeresbiologie = Papers and discussions. First European Symposium on Marine Biology = Rapports et discussions. Premier symposium européen sur biologie marine. European Marine Biology Symposia, 1. Helgoländer Wissenschaftliche Meeresuntersuchungen, 15(1-4). 669 pp., more
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Abstract |
1. In the Gullmar Fjord (west coast of Sweden) bottom test squares had been sampled 40 years ago byGislén (1929–30). Studying the same squares in 1966, using skin diving equipment, has led to different results in regard to the fauna and flora found.2. If the old records are compared with a number of new ones, obtained from the same place and depth, the degree of variation encountered in the new samples may serve as indicator for assessing true differences between biocoenoses in 1926 and 1966.3. Differences between adjacent test squares depend mainly on the slope of the rock. Other factors which may affect the community structure over short distances are direction and light.4. Certain organisms settle on bottom areas where calm waters allow sedimentation.5. Increasing pollution demands sufficient and extensive registration of the actual situation in order to allow for comparisons. For this purpose even a lot of scattered observations can never be equal to numerous data from each of a few chosen places, which are representing the main trends in the sea bottom mosaic. |
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