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Side-scan sonar waterfall image of megaripple bedforms at 200 m depth off Sinop, Turkey. Bedforms are spaced $ 4-5 m.
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Continued exploration of the coastal area of the southern Black Sea off Sinop and Ereğli, Turkey in 2011 further documented the transition zone along the oxic/anoxic interface. Push cores collected with an ROV in sediments underlying the oxic, suboxic, and anoxic waters were analyzed for geochemistry, meiofauna, and microbiology to help characteriz...
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... are more gradual. The survey there extended from 80 m down to 270 m, well below the oxic/anoxic interface and along the upper part of the slope. During the 2000 survey bedforms were noted below 170 m and were interpreted to be the result of internal wave action ( Ballard et al., 2001). In 2011, we observed extensive bedforms at and below 200 m (Fig. 4). A transect conducted with Hercules over these features with the BlueView multibeam system showed a 4-5 m spacing of these bedforms, classifying them as megaripples. Areas of heavy trawl scarring were also observed off Sinop, with the highest density near the shelf ...
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Citations
... Nautilus expeditions in the Black Sea in 2011 and 2012 followed work by Robert Ballard in 2000 and 2003 that located four Byzantine shipwrecks off Sinop. These expeditions discovered additional shipwrecks, both off Sinop as well as off Ereğli along the northern coast of Turkey (Brennan et al., 2013(Brennan et al., , 2016. Many of these wrecks exhibited trawl damage, which we had also documented on ancient shipwrecks in the Aegean Sea (Brennan et al., 2012, Brennan, Chap. ...
... One wreck in the Black Sea, Ereğli E, was of particular importance for a number of reasons. It is the oldest shipwreck in deep water found along the southern Black Sea coast of Turkey, and also exhibited extensive damage from trawls (Brennan et al., 2013(Brennan et al., , 2016Davis et al., 2018). The wreck was discovered in 2011 and mapped with video, still cameras and multibeam sonar. ...
Professor Thijs Maarleveld of the University of Southern Denmark and co-founder of the ICOMOS International Committee on the Underwater Cultural Heritage (ICUCH), was a fierce guardian of underwater cultural heritage and proponent of the UNESCO recommendation of in situ preservation as a first option. Despite his unfortunate and untimely passing in 2020, Prof. Maarleveld’s efforts to combat the misrepresentation of commercial salvage as archaeological investigation remains a beacon in the field and a reminder of best practices for protecting UCH. He championed the guiding principle that ‘the preservation in situ of underwater cultural heritage shall be considered as the first option’. Maarleveld noted that ‘the principle to consider in situ preservation first is not to be confused with the foregone conclusion that in situ preservation is what is to be decided to’ (2016, p. 478), only that it is considered as a first option. In addition, strides have been made by UNESCO and other organisations to develop tools for preservation in situ of shipwreck sites that contribute to long term management options but do not ‘reduce a central principle to a management tool’ and it is even understood that there are situations and conditions in which in situ preservation is not a preferred or feasible option (Maarleveld, 2016). However, there are those that have used this as a way to argue instead for commercial salvage of any shipwrecks, not just those that are threatened.
... As exploration and surveys in deep coastal waters expand, shipwreck sites are frequently discovered to be heavily entangled in fishing nets or broken and scattered by trawl doors and weights (Kingsley 2010;Brennan et al. 2012Brennan et al. , 2013. Historic and ancient shipwrecks are both irreplaceable cultural sites and features of the modern seabed that serve as important artificial reef habitats (Walker et al. 2007). ...
... As exploration and surveys in deep coastal waters expand, shipwreck sites are frequently discovered to be heavily entangled in fishing nets or broken and scattered by trawl doors and weights (Kingsley 2010;Brennan et al. 2012Brennan et al. , 2013. Historic and ancient shipwrecks are both irreplaceable cultural sites and features of the modern seabed that serve as important artificial reef habitats (Walker et al. 2007). ...
The book can be downloaded at https://tudav.org/en/our-fields/publications/books/
The battleships sunk during the Çanakkale Naval and Gallipoli Land Battles, their stories 108 years ago, and their current situations are examined from historical, military, cultural, and marine biodiversity perspectives. Known as the most powerful and deadliest of their time, these battleships, lying at the depths, for more than a century, are now shelters for marine species and biodiversity hotspots. In addition to the importance of biodiversity on and around the shipwrecks, the book includes social issues such as evaluating the shipwrecks as our cultural heritage and declaring them as new touristic destinations. As TUDAV, on the 100th anniversary of our Republic, we dedicate this book to those who lost their lives for their country in the Gallipoli Wars.
... As exploration and surveys in deep coastal waters expand, shipwreck sites are frequently discovered to be heavily entangled in fishing nets or broken and scattered by trawl doors and weights (Kingsley 2010;Brennan et al. 2012Brennan et al. , 2013. Historic and ancient shipwrecks are both irreplaceable cultural sites and features of the modern seabed that serve as important artificial reef habitats (Walker et al. 2007). ...
The phenomenon of ghost fishing, characterized by the persistent capture of marine organisms by lost or abandoned fishing gear, poses a significant threat to underwater cultural heritage, particularly around historic shipwrecks. This study focused on the ghost fishing and its impact on shipwrecks in the Gallipoli Campaign during World War I in Çanakkale, Türkiye. Underwater surveys were carried out between July and September 2023. The research explores the entanglement of fishing gear around these shipwrecks, assessing its ecological consequences on marine life and the structural integrity of the shipwrecks. The study also emphasizes the need for comprehensive documentation, monitoring, and management strategies to mitigate the adverse effects of ghost fishing on both biodiversity and historical artifacts. Recommendations include establishing monitoring programs, involving local communities, raising awareness, implementing regulations, and organizing underwater cleanup events.
... C-transforms, also referred to as cultural or anthropogenic processes, are associated with the impact of humans. There are numerous possible sources of human activity, which can influence underwater sites, including the construction of underwater pipelines, development of renewables, oil and gas infrastructure, port structures, cable laying, dredging, illegal salvage, disposal of material, bottom trawling and sport diving, occasionally ending up in looting (Stewart 1999;Gibbs 2006;Quinn and Boland 2010;Brennan et al. 2013Brennan et al. , 2016. Excavations and invasive research conducted at shipwreck sites also change the site permanently, and are therefore also classified as formation processes (Muckelroy 1978). ...
... This equilibrium state is dynamic, meaning that it can be perturbed by external or internal forces. This perturbation in the system can result in either a new equilibrium state or maintenance of the current one, depending on the system's capacity to absorb external forces (Quinn 2006;Quinn and Boland 2010;Astley 2016 (Gibbs 2006;Brennan et al. 2013), whereas others are nearly static, located in more stable physical environments (Eriksson and Rönnby 2012). What is common is that all wreck sites are characterized by a negative disequilibrium trend, as they undergo a gradual degradation due to chemical (i.e., corrosion) and biological (e.g., wood-boring organisms) ...
Shipwrecks not only provide unique opportunities to investigate relatively unaltered archaeological deposits, but they are also linked to environmental, heritage management and marine spatial planning issues. Physical processes, comprising linked hydro- and sediment-dynamics, can determine the pathways of evolution of shipwreck sites. For example, water flowing around a submerged wreck may cause scour, and together with changes in local geomorphology, can greatly influence the preservation state of the wreck. This geomorphic change can be exacerbated further by anthropogenic activities. This complex interplay between hydro-dynamics, geomorphic change, anthropopressure and structural deterioration remains poorly understood. Consequently, monitoring and management strategies capable of conserving this vast and finite submerged resource remain inefficient.
This thesis aims to extend our knowledge of the influence of combined sediment- and hydro-dynamic processes on the in-situ preservation of fully submerged, historic wreck sites. This study uses multibeam echosounder (MBES) data of exceptional, centimetric resolution collected over ten metal-hulled shipwrecks standing proud on the seabed in the Irish Sea between water depths of 26 and 84 m. Additional seabed and sub-seabed geological and hydrodynamic data are derived from sediment grabs, shallow-seismics and an oceanographic model. This unique combination of datasets is used in three complementary studies corresponding to the research objectives set out in the thesis.
Residual relief modelling (RRM) is tested for the objective mapping and delineation of wreck-related scour features, enabling their quantitative description. RRM relies on high-pass filtering of digital elevation model (DEM) data and is enhanced with breakpoint classification, with final separation of the features of interest supported by DEM visualisation enhancement techniques. The results indicate that the semi-automated workflow is time-efficient and quantifies the products of scour with improved objectivity when compared to manual digitisation. Development of the method has important implications for site formation studies and decision-making in in-situ preservation planning.
The temporal and spatial scales at which sediment erosion and deposition occur around wrecks remain largely unknown. Analysis of timelapse MBES survey data successfully captures true site extents and allows for the investigation of weekly, annual, multi-annual and decadal seabed changes, significantly expanding the number of case-studies reported for shipwreck site scour. Results of difference modelling show major changes at all time intervals for sites located in sand‐dominated environments, whereas the seabed around wrecks settled in multimodal sediments shows virtually no geomorphic change outside of vertical measurement uncertainty (±30 cm). Quantification of local environmental processes and factors, including bed shear stress, sediment supply, and spatial barriers to scour explains variability in geomorphic change and aids predictions of future site dynamics. The study demonstrates that individual wrecks in similar shelf sea regions can be in very different equilibrium states with their environment, which has critical implications for their in-situ management.
Computational fluid dynamics (CFD) is used in conjunction with high-resolution MBES data-derived 3D wreck models to simulate tidal flows at two contrasting sites. Intricate patterns of wake and horseshoe vortices are observed, and modelled wall shear stresses successfully explain geomorphic change recorded in 4-year and one-week interval difference models. Moreover, substantial damage is detected on the wreck structures, correlated with areas of elevated wall shear stress and pressure in CFD simulations. The combined approach aids site management and provides analogies for offshore engineering.
It is anticipated that new knowledge realised in this study on the multi-method characterization of physical site formation processes at shipwreck sites will aid decision making in underwater heritage management and marine spatial planning.
... As a result of the Black Sea Expedition of the E/V Nautilus in 2012, Brennan et al. (2013) presented the first data about meiobenthos composition at three stations in the oxic/suboxic/ anoxic interface of the southern Black Sea (off Sinop shores, Turkey). The highest total abundance of meiobenthos was found in the oxic sediment core and the lowest in the anoxic core. ...
Investigations were conducted at nine stations along the oxic/anoxic interface in the Istanbul Strait’s (Bosphorus) outlet area of the Black Sea (ISBS). Present work stands as the first study on the distribution patterns of nematodes along water depths between 75 m and 300 m at the ISBS and gives information on the variability of the trophic relationships of nematodes with oxygen depletion and the presence of toxic hydrogen sulfide in the environment. Nematodes were represented by 137 species from 63 genera and 30 families at the studied depths. 34 species were reported for the first time from Turkey. The presented results showed that most of the nematode species in this region were identified only to the genus and even only to the family or order level. This suggested that the fauna of free-living nematodes of the Black Sea as a whole is much more diverse than is currently known, and requires further taxonomic studies.
... The dynamics of equilibrium varies across wreck sites, with some subject to disruptions by storms (Fernández-Montblanc et al., 2016, 2018McNinch et al., 2006), varying tidal currents (Astley, 2016;Quinn & Smyth, 2018), or anthropogenic impacts (Brennan et al., 2013;Gibbs, 2006), whereas others are nearly static, located in more stable physical environments (Eriksson & Rönnby, 2012). What is common is that all wreck sites are characterized by a negative disequilibrium trend, as they undergo a gradual degradation due to chemical (i.e., corrosion) and biological (e.g., wood-boring organisms) formation processes (Foecke et al., 2010;Gregory, 2020;Pournou, 2017;Taormina et al., 2020). ...
Shipwrecks are an integral part of our maritime archaeological landscape and are associated with diverse societal and cultural interests, yielding significant management challenges. Coupled hydrodynamic and geomorphological processes significantly impact the effective in-situ preservation of these fragile sites. Here we assess sediment budget change and hydrodynamic triggers at metal-hulled shipwrecks lost between 1875 and 1918, all located in the tidally dominated Irish Sea at depths between 26 and 84 m. This is conducted using time-lapse, multibeam echosounder surveys at multiannual, annual and weekly time-steps, supported by sediment grain-size analysis, modelled ocean currents and shallow-seismic data. Results indicate significant changes at all time-steps for sites located in sand dominated environments, while the seabed around shipwrecks settled in multimodal sediments shows virtually no change outside of measurement errors (±30 cm). Variability in geomorphic change is attributed to local environmental factors, including bed shear stress, sediment supply and spatial barriers to scour. We demonstrate that individual wrecks in similar shelf sea regions can be in very different equilibrium states, which has critical implications for the in-situ management of underwater cultural heritage.
... These inputs help support aquatic ecosystems as wood can contribute~50% of the nitrogen pool in rivers and can provide substrates for microbial N fixers that contribute an additional 5-10% of N supply (Triska et al. 1984). Conventional wisdom, however, suggests that the decomposition of organic carbon proceeds relatively slowly in water, based on the slow turnover times of carbon in soils (Battin et al. 2008), and the recovery of long-preserved archeological remains at the bottom of lakes and oceans (Brennan et al. 2013). While slow decay rates in aquatic ecosystems have been associated with anoxic conditions that prevent the enzymatic catabolism of lignin (Janusz et al. 2017), or the absence of key guilds of white-rot fungi that predominate on land (Jones and Choeyklin 2008), terrestrial organic carbon released to aquatic ecosystems is now recognized to be less recalcitrant than once thought (Hedges et al. 1997). ...
Wood is a major carbon input into aquatic ecosystems and is thought to decay slowly, yet surprisingly little terrestrial carbon accumulates in marine sediments. A better mechanistic understanding of how habitat conditions and decomposer communities influence wood decay processes along the river–estuary–ocean continuum can address this seeming paradox. We measured mass loss, wood element, and polymer concentrations, quantified invertebrate‐induced decay, and sequenced fungal communities associated with replicate sections of Guazuma branch wood submerged in freshwater, estuarine, and near‐shore marine habitats and placed on the soil surface in nearby terrestrial habitats in three watersheds in the tropical eastern Pacific. Over 15 months, we found that wood decayed at similar rates in estuarine, marine, and terrestrial sites, reflecting the combined activity of invertebrate and microbial decomposers. In contrast, in the absence of shipworms (Teredinidae), which accounted for ~40% of wood mass loss in the estuarine habitats, decay proceeded more slowly in freshwater. Over the experiment, wood element chemistry diverged among freshwater, estuarine, and marine habitats, due to differences in both nutrient losses (e.g., potassium and phosphorus) and gains (e.g., calcium and aluminum) through decay. Similarly, we observed changes in wood polymer content, with the highest losses of cellulose, hemicellulose, and lignin moieties in the marine habitat. Aquatic fungal communities were strongly dominated by ascomycetes (88–99% of taxa), compared to terrestrial communities (55% ascomycetes). Large differences in fungal diversity were also observed across habitats with threefold higher richness in terrestrial than freshwater habitats and twofold higher diversity in freshwater than estuarine/marine habitats. Divergent decay trajectories across habitats were associated with widespread order‐level differences in fungal composition, with distinct communities found in freshwater, estuarine and marine habitats. However, few individual taxa that were significantly associated with mass loss were broadly distributed, suggesting a high level of functional redundancy. The rapid processing of wood entering tropical rivers by microbes and invertebrates, comparable to that on land, indicates that estuaries and coastal oceans are hotspots not just for the processing of particulate and dissolved organic carbon, but also for woody debris and for the breakdown of lignin, the most recalcitrant polymer in plant tissue.
... These inputs help support aquatic ecosystems as wood can contribute ~50% of the nitrogen pool in rivers, and can provide substrates for microbial N fixers that contribute an additional 5-10% of N supply (Triska et al. 1984). Conventional wisdom, however, suggests that the decomposition of organic carbon proceeds relatively slowly in water, based on the slow turnover times of carbon in soils (Battin et al. 2008), and the recovery of long-preserved archeological remains at the bottom of lakes and oceans (Brennan et al. 2013). While slow decay rates in aquatic ecosystems has been associated with anoxic conditions that prevent the enzymatic catabolism of lignin (Janusz et al. 2017), or the absence of key guilds of white-rot fungi that predominate on land (Jones and Choeyklin 2008), terrestrial organic carbon released to aquatic ecosystems is now recognized to be less recalcitrant than once thought (Hedges et al. 1997). ...
Identifying the drivers of decomposition is critical for understanding carbon cycling dynamics in forest ecosystems. Woody biomass is an important pool of carbon, composed of bark and underlying wood which vary in structure, nutrient concentrations and exposure to the environment. We hypothesized that higher nutrient concentrations in bark would speed the decomposition of underlying wood, and that this effect would be greater in streams, where nutrients are less available to decomposers than on land.
Replicate branches of three tree species, with and without bark, were placed in streams and on land in a lowland tropical forest in Panama. After 3 and 11 months of decomposition, we measured mass loss and nitrogen (N) concentrations and sequenced the fungal and bacterial communities of both wood and bark tissues.
While bark decomposed faster than the underlying wood and had higher N concentrations, bark presence slowed wood mass loss. Nitrogen concentration could account for interspecific variation in wood mass loss, but not bark mass loss. In contrast, bark mass loss, but not wood mass loss, was faster in streams than on land, suggesting fragmentation is more important for bark mass loss in streams. Differences in fungal and bacterial community composition between bark and wood substrates were significant but small.
Our results indicate that bark can slow wood decomposition instead of promoting it, and that at least for branch wood, the primary drivers of decomposition differ between bark and wood. Differences in the factors driving decomposition rate between bark and wood suggest that the contribution of bark to the decomposition of woody biomass may depend on habitat.
A free Plain Language Summary can be found within the Supporting Information of this article.
... Moreover, the reuse in the ceiling of the Kyrenia ship of a plank with tetrahedral recesses from a sewn boat (Steffy 1985, 95) is a clue that proves a certain proximity and familiarity between the Kyrenia vessel and the Greek sewn-boat tradition. Moreover, at the start of the 3 rd century BCE, the Ereğli E wrecksite, recently discovered in the Black Sea (Brennan et al. 2013;Davis et al. 2018), shows that the Greek tradition of sewn boats did not suddenly vanish with the ultimate step of evolution evidenced by the Kyrenia wreck. ...
... Štoviše, reupotreba platice s tetraedalnim utorima sa šivanog broda kao podnice za brod Kyrenia dokaz je za određenu bliskost i povezanost između broda Kyrenia i grčke tradicije šivanih brodova. Brodolom Ereğli E, recentno otkriven u Crnom moru (Brennan et al. 2013;Davis et al. 2018), koji se datira na početak 3. st. pr. ...
