Figure - available from: Frontiers in Marine Science
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Selected pipeline associations. (A) Plastic bottle c. 730 m; (B) Plastic bag c. 1333 m; (C) Fishing net c. 1696 m; (D) Plant debris c. 1768 m.
Source publication
Large structures are introduced into deep-water marine environments by several industrial activities, including hydrocarbon exploitation. Anthropogenic structures can alter ecosystem structure and functioning in many marine ecosystems but the responses on continental margins are poorly known. Here, we investigate the short-term response of benthic...
Citations
... As far as the echinoderms of this region are concerned, there is not a single quantitative study dedicated to the community ecology of this group along a 10 000 km stretch of the West African coast. However, some earlier studies based on analysis of bottom images and ROV movies analysed megaepibenthic communities in Ivory Coast (Lebrato and Jones, 2009), Mauretania (Jones and Brewer 2012), Nigeria (Jones et al., 2013) and Angola (Biede et al., 2022). The majority of studies, mostly published in the first half of the 20th century, has been focused on echinoderm taxonomy (e.g. ...
... Trawling devices that are often used in the study of echinoderms tend to mix all the animals collected over a large distance, and from various microhabitats, resulting in the underestimation of smaller-sized animals and the inability to link distribution patterns with data about environmental properties (Jozwiak et al., 2020). West African studies conducted mostly in batyal and based on bottom images and movies demonstrated relatively low number of species and low abundances (Lebrato and Jones, 2009;Jones and Brewer, 2012;Jones et al., 2013;Biede et al., 2022). At the same time, our results suggests important disproportions between data from van Veen grabs and movies, especially in species richness and species composition and bottom imaging techniques are certainly omitting the small species buried in the sediments. ...
All earlier studies of the West African echinoderm fauna have focused on taxonomy, and general knowledge about benthic community responses to various human related threats are poorly diagnosed and not monitored along the whole African coast. Our analysis of diversity and distribution patterns of Ghanaian echinoderms yielded 36 species. Material was collected at nine transects distributed along the coast of Ghana (25-1000 m depth range, total of over 270 samples). Gradual decreases in species richness, diversity, evenness and abundance were observed along the depth gradient, with the most diverse fauna being recorded on the shelf (25-50 m). The most abundant species were Ophiactis luetkeni and Ophiothrix congensis, although both had very patchy distributions. Cluster analysis separated shelf communities (25-100 m) from slope communities (500-1000 m), although on a low level of similarity. Our analysis allowed to select most vulnerable benthic habitats that should be amongst priorities of the future monitoring. Local influence of arsenic was observed at some shelf sites, while slope fauna was affected by elevated levels of hydrocarbons and barium. Changes in salinity and fluorescence also influenced echinoderm assemblages. The most general trend showed patchily distributed, diverse shallow water fauna being influenced by increased microhabitat diversity and food availability, while depauperate slope fauna was affected by local disturbances associated with oil extraction. Tropical echinoderm communities have a great potential as indicators of even minor and local pollution, although high patchiness and low abundance creates difficulties in the multivariate analysis. High sampling effort and high number of replicates allowed to minimise those problems and demonstrated small scale microhabitat diversity.
... Various attempts have been made to determine the positive and negative effects of pollution and corrosion from offshore structures on the behavioral patterns of opportunistic species [10][11][12][13][14][15]. The mutual impacts of opportunistic organisms and subsea anthropogenic structures, such as offshore oil platforms, can be summarized in two focus areas: ...
This research examines the factors contributing to the exterior material degradation of subsea oil and gas pipelines monitored with autonomous underwater systems (AUS). The AUS have a role of gathering image data that is further analyzed with artificial intelligence data analysis methods. Corrosion and potential ruptures on pipeline surfaces are complex processes involving several competing elements, such as the geographical properties, composition of soil, atmosphere, and marine life, whose eflt in substantial environmental damage and financial loss. Despite extensive research, corrosion monitoring and prediction remain a persistent challenge in the industry. There is a lack of knowledge map that can enable image ausing an AUS to recognize ongoing degradation processes and potentially prevent substantial damage. The main contribution of this research is the knowledge map for increased context and risk awareness to improve the reliability of image-based monitoring and inspection by autonomous underwater systems in detecting hazards and early signs of material degradation on subsea pipeline surfaces.
... Various attempts have been made to determine the positive and negative effects of pollution and corrosion from offshore structures on the behavioral patterns of opportunistic species [10][11][12][13][14][15]. The mutual impacts of opportunistic organisms and subsea anthropogenic structures, such as offshore oil platforms, can be summarized in two focus areas: ...
This research examines the factors contributing to the exterior material degradation of subsea oil and gas pipelines monitored with autonomous underwater systems (AUS). The AUS have a role of gathering image data that is further analyzed with artificial intelligence data analysis methods. Corrosion and potential ruptures on pipeline surfaces are complex processes involving several competing elements, such as the geographical properties, composition of soil, atmosphere, and marine life, whose effects can result in substantial environmental damage and financial loss. Despite extensive research, corrosion monitoring and prediction remain a persistent challenge in the industry. There is a lack of knowledge map that can enable image analysis using an AUS to recognize ongoing degradation processes and potentially prevent substantial damage. The main contribution of this research is the knowledge map for increased context and risk awareness to improve the reliability of image-based monitoring and inspection by autonomous underwater systems in detecting hazards and early signs of material degradation on subsea pipeline surfaces.
Marine litter is one of the most pervasive and fast-growing aspects of contamination in the global ocean, and has been observed in every environmental setting, including the deep seafloor where little is known about the magnitude and consequences of the problem. Submarine canyons, the main conduits for the transport of sediment, organic matter and water masses from shallow to abyssal depths, have been claimed to be preferential pathways for litter transport and accumulation in the deep sea. This is supported by ongoing evidence of large litter piles at great water depths, highlighting efficient transfer via canyons. The aim of this article is to present an overview of the current knowledge about marine litter in submarine canyons, taking a geological, process-based point of view. We evaluate sources, transport mechanisms and deposition of litter within canyons to assess the main factors responsible for its transport and accumulation in the deep sea. Few studies relate litter distribution to transport and depositional processes; nevertheless, results from available literature show that canyons represent accumulation areas for both land-based and maritime-based litter. Particularly, accumulation of fishing-related debris is mainly observed at the canyon heads and walls and is related to fishing activities carried out in and adjacent to canyons, while transport and accumulation of general waste and plastic along canyon axes can be related to different mechanisms, encompassing enhanced bottom currents, dense water cascading and turbidity currents, and is related to the proximity of canyons to shore. Global assessment of canyons exposure to riverine plastic inputs and fishing-related debris indicates varying susceptibility of canyons to litter, also highlighting that most of the canyons prone to receive large amounts of anthropogenic debris have not yet been surveyed. Considering that litter research in canyons is still in its infancy, several knowledge gaps need to be filled before the role of canyons as litter traps and the implication for benthic ecosystems can be fully understood.
