Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea
This study contributes to a better understanding of geogenic reef distribution in the southern Baltic Sea and highlights the implications of survey-related factors on automated boulder classification when utilizing data from multiple surveys. The distribution of hard grounds and reefs is needed as a...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2023-06-01
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| Series: | Frontiers in Earth Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2023.1155765/full |
| _version_ | 1797809111211966464 |
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| author | Agata Feldens Agata Feldens Denise Marx Anne Herbst Anne Herbst Alexander Darr Svenja Papenmeier Matthias Hinz Michael L. Zettler Peter Feldens |
| author_facet | Agata Feldens Agata Feldens Denise Marx Anne Herbst Anne Herbst Alexander Darr Svenja Papenmeier Matthias Hinz Michael L. Zettler Peter Feldens |
| author_sort | Agata Feldens |
| collection | DOAJ |
| description | This study contributes to a better understanding of geogenic reef distribution in the southern Baltic Sea and highlights the implications of survey-related factors on automated boulder classification when utilizing data from multiple surveys. The distribution of hard grounds and reefs is needed as a baseline for geological and biological studies, but also for offshore construction, navigation and coastal management. In this study we provide maps of the distribution of geogenic reefs for about 750 km2 in the southern Baltic Sea, at the sites Wismar Bay, Darss Sill and Plantagenet Ground. The maps are based on full-coverage backscatter surveys with different side scan sonar and multibeam echo sounder systems. The distribution and number of boulders in the backscatter maps was determined using a convolutional neural network combined with quality control by human experts. The extent of the geogenic reefs was calculated on the basis of the number of boulders in 50 m x 50 m grid cells. We compare the results with previous reef maps based on point sampling, which show reefs of either biogenic or geogenic origin. According to the earlier maps, 11% of the Plantagenet Ground seabed was classified as reef habitat type. This is similar to the result of our study (12%), although we only considered reefs of geogenic origin. In the Darss Sill, geogenic reefs are larger in this study than in previous maps (30% versus 23%). In both regions, the spatial distribution of reefs differs significantly between old and new maps. For Wismar Bay, previous maps classify 3% of the seafloor as habitat type reef, whereas this study classifies 35% as geogenic reef. The use of automated classification during seafloor mapping allowed large areas to be interpreted in a few days. It also provided more information on the distribution of boulders within the geogenic reef. However, the boulder distribution maps show the negative effects of survey geometry, frequency and environmental conditions on automated boulder classification when data from different surveys are combined. |
| first_indexed | 2024-03-13T06:47:42Z |
| format | Article |
| id | doaj.art-c16c94481af1406fb7c039e98794215a |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-03-13T06:47:42Z |
| publishDate | 2023-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-c16c94481af1406fb7c039e98794215a2023-06-08T05:12:03ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632023-06-011110.3389/feart.2023.11557651155765Distribution of boulders in coastal waters of Western Pomerania, German Baltic SeaAgata Feldens0Agata Feldens1Denise Marx2Anne Herbst3Anne Herbst4Alexander Darr5Svenja Papenmeier6Matthias Hinz7Michael L. Zettler8Peter Feldens9Leibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanySubsea Europe Services GmbH, Rostock, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyUniversity of Rostock, Faculty of Interdisciplinary Research, Department Maritime Systems, Rostock, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyLeibniz Institute for Baltic Sea Research Warnemünde, Warnemünde, GermanyThis study contributes to a better understanding of geogenic reef distribution in the southern Baltic Sea and highlights the implications of survey-related factors on automated boulder classification when utilizing data from multiple surveys. The distribution of hard grounds and reefs is needed as a baseline for geological and biological studies, but also for offshore construction, navigation and coastal management. In this study we provide maps of the distribution of geogenic reefs for about 750 km2 in the southern Baltic Sea, at the sites Wismar Bay, Darss Sill and Plantagenet Ground. The maps are based on full-coverage backscatter surveys with different side scan sonar and multibeam echo sounder systems. The distribution and number of boulders in the backscatter maps was determined using a convolutional neural network combined with quality control by human experts. The extent of the geogenic reefs was calculated on the basis of the number of boulders in 50 m x 50 m grid cells. We compare the results with previous reef maps based on point sampling, which show reefs of either biogenic or geogenic origin. According to the earlier maps, 11% of the Plantagenet Ground seabed was classified as reef habitat type. This is similar to the result of our study (12%), although we only considered reefs of geogenic origin. In the Darss Sill, geogenic reefs are larger in this study than in previous maps (30% versus 23%). In both regions, the spatial distribution of reefs differs significantly between old and new maps. For Wismar Bay, previous maps classify 3% of the seafloor as habitat type reef, whereas this study classifies 35% as geogenic reef. The use of automated classification during seafloor mapping allowed large areas to be interpreted in a few days. It also provided more information on the distribution of boulders within the geogenic reef. However, the boulder distribution maps show the negative effects of survey geometry, frequency and environmental conditions on automated boulder classification when data from different surveys are combined.https://www.frontiersin.org/articles/10.3389/feart.2023.1155765/fullBaltic Seabouldersside scan sonarbackscatterneural networkhabitat mapping |
| spellingShingle | Agata Feldens Agata Feldens Denise Marx Anne Herbst Anne Herbst Alexander Darr Svenja Papenmeier Matthias Hinz Michael L. Zettler Peter Feldens Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea Frontiers in Earth Science Baltic Sea boulders side scan sonar backscatter neural network habitat mapping |
| title | Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea |
| title_full | Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea |
| title_fullStr | Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea |
| title_full_unstemmed | Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea |
| title_short | Distribution of boulders in coastal waters of Western Pomerania, German Baltic Sea |
| title_sort | distribution of boulders in coastal waters of western pomerania german baltic sea |
| topic | Baltic Sea boulders side scan sonar backscatter neural network habitat mapping |
| url | https://www.frontiersin.org/articles/10.3389/feart.2023.1155765/full |
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