Journal articles: 'Marine environment conditions'

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M, Halafawi. "The Impact of Marine Environment on Jackup Rig Stability." Petroleum & Petrochemical Engineering Journal 4, no. 4 (2020): 1–16. http://dx.doi.org/10.23880/ppej-16000238.

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Changing the conditions of offshore environment influences the offshore units' stability. In paper, a study of the impact of marine environment on a jackup rig was implemented. Firstly, the procedures of departure, transit, and emplacement on any emergency jacking location / stand by location are reviewed. After that, the conditions of weather forecasting are predicted and computed such as wave and wind lengths, speeds, and heights. Maps of changing wind and wave conditions are plotted. Surveying methods are used to determine the final location of the jackup rig. Maps of positioning the jackup rig are constructed. Additionally, the impact forces on the rig derrick are therefore computed. The developed results are effectively predicting the safe conditions and optimizing the positioning survey of the rig.

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Chasco, Brandon, Brian Burke, Lisa Crozier, and Rich Zabel. "Differential impacts of freshwater and marine covariates on wild and hatchery Chinook salmon marine survival." PLOS ONE 16, no. 2 (February 9, 2021): e0246659. http://dx.doi.org/10.1371/journal.pone.0246659.

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Large-scale atmospheric conditions in the Northeast Pacific Ocean affect both the freshwater environment in the Columbia River Basin and marine conditions along the coasts of Oregon, Washington, and British Columbia, resulting in correlated conditions in the two environments. For migrating species, such as salmonids that move through multiple habitats, these correlations can amplify the impact of good or poor physical conditions on growth and survival, as movements among habitats may not alleviate effects of anomalous conditions. Unfortunately, identifying the mechanistic drivers of salmon survival in space and time is hindered by these cross-habitat correlations. To address this issue, we modeled the marine survival of Snake River spring/summer Chinook salmon with multiple indices of the marine environment and an explicit treatment of the effect of arrival timing from freshwater to the ocean, and found that both habitats contribute to marine survival rates. We show how this particular carryover effect of freshwater conditions on marine survival varies by year and rearing type (hatchery or wild), with a larger effect for wild fish. As environmental conditions change, incorporating effects from both freshwater and marine habitats into salmon survival models will become more important, and has the additional benefit of highlighting how management actions that affect arrival timing may improve marine survival.

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Yin, Lili, Rubo Zhang, Hengwen Gu, and Peng Li. "Research on Cooperative Perception of MUSVs in Complex Ocean Conditions." Sensors 21, no. 5 (February 28, 2021): 1657. http://dx.doi.org/10.3390/s21051657.

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Since the working environment of Multiple Unmanned Surface Vehicles (MUSVs) is accompanied by a large number of uncertainties and various hazards, in order to ensure the collision avoidance capability of MUSVs in complex marine environments, the perception of complex marine environments by MUSVs is the first problem that needs to be solved. A cooperative perception framework with uncertain event detection, cooperative collision avoidance pattern recognition and environmental ontology model is proposed to realize the cooperative perception process of MUSVs using ontology and Bayesian network theory. The cooperative perception approach was validated by simulating experiments. Results show the effectiveness of cooperative perception approach.

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Beltrán-Sanahuja, Ana, Nuria Casado-Coy, Lorena Simó-Cabrera, and Carlos Sanz-Lázaro. "Monitoring polymer degradation under different conditions in the marine environment." Environmental Pollution 259 (April 2020): 113836. http://dx.doi.org/10.1016/j.envpol.2019.113836.

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Bisbal, Gustavo A., and Willis E. McConnaha. "Consideration of ocean conditions in the management of salmon." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 9 (September 1, 1998): 2178–86. http://dx.doi.org/10.1139/f98-108.

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An ecologically based conceptual foundation is presented as a way to incorporate environmental variability in salmon management. The argument addresses the problem of accommodating marine environment variability through actions in freshwater. We argue for an approach that considers marine and freshwater environments as integral components of a larger salmonid ecosystem. This contrasts with previous propositions that either relied heavily on technological fixes in the freshwater environment or questioned the value of any recovery effort designed to withstand overwhelming ocean forces. Salmon management requires a more holistic approach incorporating modern understanding of the salmonid ecosystem and its variability. We suggest two strategies. The first calls for deliberate improvement of estuarine and nearshore ocean conditions through regulation of upstream flows, river operations, hatchery production, and other actions. The second calls for improving the resilience of salmon to a variable environment. This requires relaxing anthropogenic factors that hinder the natural range of salmon life history diversity within and between populations, a survival mechanism that evolved in response to changing conditions. These strategies recognize that although the ocean primarily determines overall salmon abundance, management actions, particularly in freshwater, are critical to the ability of salmon to cope with a variable ocean environment.

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Di Donato, Paola, Andrea Buono, Annarita Poli, Ilaria Finore, Gennaro Abbamondi, Barbara Nicolaus, and Licia Lama. "Exploring Marine Environments for the Identification of Extremophiles and Their Enzymes for Sustainable and Green Bioprocesses." Sustainability 11, no. 1 (December 28, 2018): 149. http://dx.doi.org/10.3390/su11010149.

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Sea environments harbor a wide variety of life forms that have adapted to live in hard and sometimes extreme conditions. Among the marine living organisms, extremophiles represent a group of microorganisms that attract increasing interest in relation to their ability to produce an array of molecules that enable them to thrive in almost every marine environment. Extremophiles can be found in virtually every extreme environment on Earth, since they can tolerate very harsh environmental conditions in terms of temperature, pH, pressure, radiation, etc. Marine extremophiles are the focus of growing interest in relation to their ability to produce biotechnologically useful enzymes, the so-called extremozymes. Thanks to their resistance to temperature, pH, salt, and pollutants, marine extremozymes are promising biocatalysts for new and sustainable industrial processes, thus representing an opportunity for several biotechnological applications. Since the marine microbioma, i.e., the complex of microorganisms living in sea environments, is still largely unexplored finding new species is a central issue for green biotechnology. Here we described the main marine environments where extremophiles can be found, some existing or potential biotechnological applications of marine extremozymes for biofuels production and bioremediation, and some possible approaches for the search of new biotechnologically useful species from marine environments.

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Godfrin, Michael P., Maswazi Sihlabela, Arijit Bose, and Anubhav Tripathi. "Behavior of Marine Bacteria in Clean Environment and Oil Spill Conditions." Langmuir 34, no. 30 (July 5, 2018): 9047–53. http://dx.doi.org/10.1021/acs.langmuir.8b01319.

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Namadi, Peyman, and Zhiqiang Deng. "Optimum environmental conditions controlling prevalence of vibrio parahaemolyticus in marine environment." Marine Environmental Research 183 (January 2023): 105828. http://dx.doi.org/10.1016/j.marenvres.2022.105828.

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Petropoulos, A., I. Baziotis, Ch Anagnostou, and N. Evelpidou. "BEACHROCKS CEMENT CHARACTERISTICS AND CONDITIONS OF FORMATION. CASE STUDY PLATANIAS BEACH, CHANIA, GREECE." Bulletin of the Geological Society of Greece 50, no. 1 (July 27, 2017): 458. http://dx.doi.org/10.12681/bgsg.11747.

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Beachrocks represents a coastal deposition in the intertidal area, and studying their properties may lead to create a model which identifies the conditions of their formation (paleo-environment). This paper focuses most intently on the cement material which is able to recover the paleo-environment conditions during diagenesis of such coastal sediment. We used optical microscopy, secondary electron microscopy and Raman Spectroscopy to characterize the cement texture, mineralogy and chemistry in the beachrocks. The existence of pure calcite primarily controlled by the meteorite water, while Mg-calcite appears between the lowermeteoric and the upper marine phreatic zone. Finally, the presence of aragonite associated with the marine phreatic to lower marine vadose environment.

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Chou, Loke Ming. "Enhancing Marine Biodiversity in Singapore’s Urbanizing Coastal Environment." International Journal of Environmental Science and Development 11, no. 11 (2020): 519–23. http://dx.doi.org/10.18178/ijesd.2020.11.11.1301.

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Urbanization of coastal cities has resulted in extensive physical modification of the coast that is commonly accompanied by habitat destruction or degradation, marine biodiversity loss and ecosystem services decline. Conversion of the natural environment to a human-modified one is often permanent, and it is important that development considerations take into account biodiversity enhancement of the ‘new’ environment. Development of biological communities in the modified environment takes time and is unlikely to return to levels once supported by the original habitats, but efforts can be made to facilitate the establishment of biodiversity that is suited to the new environmental conditions. Active interventions such as water quality management and ecological restoration can help to transform the urbanized coastal environment into a suitable biodiversity support zone. Observations of marine biodiversity in marinas and restoration of corals on artificial structures in Singapore support this prospect. Assessment of the biodiversity in three marinas indicated that they can function as marine biodiversity refugia, especially with their relatively high artificial structural complexity and when designed with basic ecological considerations to enhance marine biodiversity. Separately, reef restoration projects give rise to the possibility of colonizing seawalls with corals and other reef-associated species, as well as improving degraded reefs and creating reef communities in areas originally devoid of corals due to the heavy sediment load of urbanized coastal waters. Maintaining marine biodiversity in challenging environmental conditions resulting from urbanization can help to ensure continued provision of some level of ecosystem services.

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Doukari, M., and K. Topouzelis. "UAS DATA ACQUISITION PROTOCOL FOR MARINE HABITAT MAPPING: AN ACCURACY ASSESSMENT STUDY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B3-2020 (August 22, 2020): 1321–26. http://dx.doi.org/10.5194/isprs-archives-xliii-b3-2020-1321-2020.

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Abstract. Marine habitat mapping is essential for updating existing information, preserving, and protecting the marine environment. Unmanned Aerial Systems (UAS) are an important tool for monitoring and mapping coastal and marine environment because of their ability to provide very high-resolution aerial imagery.Environmental conditions have a critical role in marine mapping using UAS. This is due to the limitations of UAS surveys in coastal areas, i.e. the environmental conditions prevailing in the area. The limitations of weather and oceanographic conditions affecting the quality of marine data led to the creation of a UAS protocol for the acquisition of reliable marine information. The produced UAS Data Acquisition Protocol consists of three main categories: (i) Morphology of the study area, (ii) Environmental conditions, (iii) Flight parameters. These categories include the parameters that must be considered for marine habitat mapping.The aim of the present study is the accuracy assessment of the UAS protocol for marine habitat mapping through experimental flights. For the accuracy assessment of the UAS protocol, flights on different dates and environmental conditions were conducted, over a study area. The flight altitude was the same for all the missions, so the results were comparable. The high-resolution orthophoto maps derived from each date of the experiment were classified. The classification maps show several differences in the shape and size of the marine habitats which are directly dependent on the conditions that the habitats were mapped. A change detection comparison was conducted in pairs to examine the exact changes between the classified maps.The results emphasize the importance of the environmental conditions prevailing in an area during the mapping of marine habitats. The present study proves that the optimal flight conditions that are proposed of the UAS Data Acquisition protocol, respond to the real-world conditions and are important to be considered for an accurate and reliable mapping of the marine environment.

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Koçhan, Cemal, Gökdeniz Neşer, and Çiçek Özes. "The Fracture Toughness of PVC / GRP Sandwich Systems in Marine Environment." Advanced Composites Letters 17, no. 1 (January 2008): 096369350801700. http://dx.doi.org/10.1177/096369350801700103.

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The aim of this study is to investigate experimentally the fracture toughness of sandwich systems with the PVC foam core in marine environment with a Mode-I Cracked Sandwich Beam (CSB) test arrangement. Five CSB specimens at each condition were tested. To get the values under marine environment, one set of specimen was conditioned in a 5% solution of NaCl for a 120 h period at a constant temperature of 50°C. It has been found that the fracture toughness of the PVC foam core material slightly increases under marine environmental conditions. It can be concluded that under the conditions in this study the system with the PVC core was largely unaffected by the immersion process.

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M. K., Kozanhan. "Maritime Tanker Accidents and Their Impact on Marine Environment." Scientific Bulletin of Naval Academy XXII, no. 1 (July 15, 2019): 324–42. http://dx.doi.org/10.21279/1454-864x-19-i1-047.

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Shipping is a fundamental mode of transportation for 85 per cent of the world trade, supplying raw materials, energy, manufactured goods, foodstuffs etc. to the global population, is carried by international shipping industry. In such busy traffic, unfortunately, accidents are inevitable events. Large numbers of casualties occur at sea almost every day. Human loss and marine environmental damage, among others such as financial and property losses, are the most crucial and hazardous disasters caused by maritime accidents. There are several causes playing role in maritime accidents such as natural conditions, technical failures, route conditions, ship-related factors, human errors, cargo-related factors. There are also quite many types of maritime accidents; they include oil spill, ship grounding, fire, to mention a few. The impact of maritime accidents on the marine environment differs from one another. The main purpose of this paper is to determine and analyse the effects of maritime accidents on the marine environment. The analysis was based on data published over the past 56 years involving spills of 7000 tons oils. Within this scope, firstly, the literature related to maritime accidents involving spills was reviewed and then the statistics of maritime accidents and their impact on marine environment worldwide were analyzed and evaluated.

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Taher, A. "Corrosion Behavior of Copper-Nickel Alloy in Marine Environment (Review Paper)." Applied Mechanics and Materials 799-800 (October 2015): 222–31. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.222.

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Copper-nickel alloys have been used in many applications in marine environments because of excellent corrosion and biofouling resistance. . This investigation is cover a review of many previous studies about the behavior of these alloys in marine environments with different environmental conditions including the effect of sulphur contamination, the effect of CO2, the effect of chlorine, the effect of flow velocity, the effect of temperature and the effect of adding some alloying elements to the alloy itself. There have been conflicting results in the past about the corrosion rate values and the chemical analysis of the corrosion films in different environmental conditions. More research is needed for studying the behavior of these alloys in marine environments to provide good assessment of the corrosion resisting characteristics.

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Prudkovsky, A. A., N. P. Karaseva, M. N. Rimskaya-Korsakova, T. P. Pimenov, N. N. Rimskaya-Korsakova, and V. V. Malakhov. "First Experience of Keeping Pogonophorans (Annelida: Siboglinidae) in Laboratory Conditions." Doklady Biological Sciences 506, no. 1 (October 2022): 150–53. http://dx.doi.org/10.1134/s001249662205009x.

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Wei, Xie. "Collaborative protection of marine environment in the Guangdong-Hong Kong-Macao Greater Bay Area." E3S Web of Conferences 233 (2021): 01132. http://dx.doi.org/10.1051/e3sconf/202123301132.

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The quality of Marine ecological environment is one of the necessary conditions for building a world-class bay area. The ecological environment in the coastal waters of Guangdong-Hong Kong-Macao Greater Bay Area is seriously polluted, it is urgently needed for three places to strengthen coordinated Marine ecological and environmental management. Under the guidance of outline development plan for the Greater Bay Area and with the goal of building a Marine ecological civilization in the Greater Bay Area, the coordination mechanism of administrative management and the standard system for Marine ecological environmental protection should be improved，land and sea overall planning should be used for Marine ecological environment protection.

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Alamsyah, Vicky Verry Angga, and Danik Fitriani. "Lomban Traditions and Preservation of the Marine Environment in Jepara." E3S Web of Conferences 359 (2022): 06001. http://dx.doi.org/10.1051/e3sconf/202235906001.

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Lomban is a tradition of the Jepara people in which is carried out one week after Eid al-Fitr. Lomban is a party of fishing communities in the form of sea alms, which is now supported by the people of Jepara and outside Jepara. The center of the competition is located at Kartini Beach. This competition activity is related to the environment and marine conservation, especially in protecting the environment. The existence of the lomban tradition shows the continuity of fish living in the sea and the harmony between the marine environment, humans, and God. The lomban tradition in which there is a buffalo head larungan shows the concern of fishermen, community members, and local governments for the marine environment. With this tradition, there is an awareness that in taking fish in the sea and the natural wealth of the sea must pay attention to the survival of marine life. The marine economy taken must pay attention to the conditions of the marine environment and not damage the sea. Through the efforts of the lomban tradition, it is hoped that environmental conservation will be well maintained. Keywords: Lomban, preservation, environment, sea, Jepara.

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Liu, Shiyu, Bowen Dong, Jin Yu, Yanyan Cai, Xingqian Peng, and Xianqi Zhou. "Effect of Different Mineralization Modes on Strengthening Calcareous Sand under Simulated Seawater Conditions." Sustainability 13, no. 15 (July 23, 2021): 8265. http://dx.doi.org/10.3390/su13158265.

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Calcareous sand, as a blow-fill or construction material, is widely used in island and reef construction projects in marine environments after treatment. When microorganism-induced mineralization is used to strengthen calcareous sand, salinity and other conditions in the marine environment will adversely affect microorganisms or their mineralization process. For this reason, the two environmental conditions created by deionized water and simulated seawater were introduced to explore their effects on the growth and urease activity of Sporosarcina pasteurii. Then, the changes in the permeability and mechanical strength of calcareous sand under different mineralization methods were compared by one-dimensional sand column tests. Finally, the reinforcement mechanism was compared and analyzed based on the results of scanning electron microscopy and X-ray diffraction tests. The results show that Sporosarcina pasteurii can induce carbonate and phosphate precipitation and mineralization to strengthen calcareous sand in simulated seawater. The mineralized products greatly reduce the permeability of calcareous sand and significantly improve the mechanical strength by wrapping calcareous sand particles, filling water seepage channels and cementing adjacent particles. The reinforcement effect of carbonate mineralization is better than that of phosphate mineralization, but phosphate mineralization has less impact on the environment during the treatment process.

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Voloshinov, Sergey. "The use of information-educational environment in the training of future marine professionals: analysis of experience." Scientific Visnyk V.O. Sukhomlynskyi Mykolaiv National University. Pedagogical Sciences 66, no. 3 (2019): 53–58. http://dx.doi.org/10.33310/2518-7813-2019-66-3-53-58.

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The article actualizes the question of the suitability of the educational environment for training future marine professionals to the conditions of their future professional activity. Based on the analysis of scientific, methodological and pedagogical works, the experience of creating and implementing information and educational environments for the professional training of future marine professionals has been generalized. It is determined that such environment should include innovative educational activities, modern information and communication training and facilities for training students. The information and educational environment should be created onthe basis of a distributed infrastructure of technical and software complexes. It should be multivariate and multicomponent to accommodate all the needs of the learning process. The proliferation of cloud technologies encourages their use in the training of future marine professionals, taking into account all the risks posed by interaction with third parties in the implementation of the educational process using cloud services. Perspective in the train ing of future marine professionals is the use of intelligent training environment. It is important to ensure that future marine professionals are trained in an information and educational environment to provide end-to-end user identification, which is to ensure that users have automatic access to their resources. The author emphasizes that the effectiveness of training future marine professionals can be achieved through the appropriate organization of information and educational environment, if the creation and use of such tasks will be solved: achievement of the planned level of professional competence by all students; achievement of the planned quality of mastering the programs of training in the most rational way for the student; ensuring the desired effect of training in relation to the individual abilities of each student; most acceptable overcoming the contradictions between the increasing amount of information in a specific professional activity and a fixed time limit for its assimilation; the creation of conditions for teachers that, with the overall intensification of the training process, would not require them to increase efficiency of their physical force and moral influence.

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Bourli, Nicolina, George Iliopoulos, Penelope Papadopoulou, and Avraam Zelilidis. "Microfacies and Depositional Conditions of Jurassic to Eocene Carbonates: Implication on Ionian Basin Evolution." Geosciences 11, no. 7 (July 9, 2021): 288. http://dx.doi.org/10.3390/geosciences11070288.

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In order to decipher the paleo-depositional environments, during the Late Jurassic to Early Eocene syn-rift stage, at the margins of the Ionian basin, two different areas with exposed long sequences have been selected, Kastos Island (external margin) and Araxos peninsula (internal margin), and were examined by means of microfacies analysis and biostratigraphy. On Kastos Island, based on lithological and sedimentological features, the following depositional environments have been recognized: an open marine/restricted environment prevailed during the Early Jurassic (“Pantokrator” limestones), changing upwards into deep-sea and slope environments during the Late Jurassic and Early Cretaceous (Vigla limestones). The Upper Cretaceous (Senonian limestones) is characterized by a slope environment, whereas during the Paleogene, deep-sea and toe of slope conditions prevailed. In Araxos peninsula, Lower Cretaceous deposits (“Vigla” limestones) were accumulated in a deep-sea environment; Upper Cretaceous ones (Senonian limestones) were deposited in slope or toe of slope conditions. Paleocene limestones correspond to a deep-sea environment. In Araxos peninsula, changes occurred during the Cretaceous, whereas on Kastos Island, they occurred during the Paleocene/Eocene, related to different stages of tectonic activity in the Ionian basin from east to west.

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Mehlqvist, Kristina, Jane Wigforss-Lange, and Vivi Vajda. "A palynological study from Sweden reveals stable terrestrial environments during Late Silurian extreme marine conditions." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 105, no. 3 (September 2014): 149–58. http://dx.doi.org/10.1017/s1755691015000043.

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ABSTRACTA palynological study of the upper Silurian Öved–Ramsåsa Group in Skåne, Sweden yields a well preserved spore assemblage with low relative abundances of marine microfossils. In total, 26 spore taxa represented by 15 genera were identified. The spore assemblage is dominated by long-ranging cryptospore taxa, and the trilete spore Ambitisporites avitus-dilutus. However, key-species identified include Artemopyra radiata, Hispanaediscus lamontii, H. major, H. verrucatus, Scylaspora scripta and Synorisporites cf. libycus. Importantly, Scylaspora klintaensis was identified, allowing correlation with the Klinta 1 drillcore (Skåne). A Ludlow age is inferred for the exposed succession, which agrees well with previous conodont stratigraphy. The organic residue is dominated by phytodebris and spores, but with high relative abundances of acritarchs at two levels, possibly related to flooding surfaces.Based on the palynofacies analysis, a near-shore marine environment is proposed. The close proximity to land is inferred by the high proportions of spores, and the dispersed assemblage most likely represents the local flora growing on delta plains. The palynological signal also infers a stable terrestrial environment and vegetation, in contrast to unstable conditions in the marine environment characterised by ooid formation in an evaporitic environment. Comparisons with coeval spore assemblages from Gotland, Avalonia and Laurentia show relatively close similarities in taxonomic composition at the generic level.

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Cinelli, Claudia. "PROTECTION AND PRESERVATION OF THE ARCTIC MARINE ENVIRONMENT." Italian Yearbook of International Law Online 24, no. 1 (October 22, 2015): 159–89. http://dx.doi.org/10.1163/22116133-90000078a.

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Unique geographical and physical specificities characterize the Arctic as an extreme and fragile marine environment. Arctic specificities differ from those of any other environment in relation to which most general principles of international law have developed. International law is usually related to the regulation of the physical environment including the distinct issues of soil, water and the atmosphere rather than a combination of these components, as is the case in the ice-covered marine areas such as those composing most of the Arctic Ocean. From both historical and contemporary perspectives, the ‘Arctic question’ has typically been: does the presence of ice change the legal status of the Arctic Ocean? The answer is decidedly no. The so-called Arctic exception, relating to Article 234 UNCLOS, is clearly the exception that proves the rule. This study focuses on how both the sovereignty-based approach and the general interest approach each address the dynamic evolution of Arctic marine environmental challenges in line with UNCLOS, the “Constitution for the Oceans”. This, however, does not preclude the special conditions of the Arctic environment being factored in when Arctic and non-Arctic entities seek feasible ad hoc solutions for cooperation on common interests and concerns.

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Malešević, Nikola, Irena Ciglenečki, Elvira Bura-Nakić, Marina Carić, Iris Dupčić, Enis Hrustić, Damir Viličić, and Zrinka Ljubešić. "Diatoms in an extreme euxinic environment (Rogoznica Lake, eastern Adriatic coast)." Acta Botanica Croatica 74, no. 2 (October 1, 2015): 333–43. http://dx.doi.org/10.1515/botcro-2015-0031.

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AbstractThe Rogoznica Lake marine system is a small, karstic, naturally eutrophic and euxinic marine environment. Abundance and temporal distribution of phytoplankton was investigated in relation to environmental conditions in the period from 1998 to 2013. The 36 determined diatoms contributed 90% of the total phytoplankton abundance. The diatom composition is characterized by low species diversity and high single species abundance (up to 107 cells L-1). There were, on average, 2.6 diatom species per sample (maximum 14 diatom species per sample) reflecting extreme environmental conditions. Dominant diatoms Thalassionema nitzschioides, Cyclotella choctawhatcheeana, Dactyliosolen fragilissimus and Chaetoceros curvisetus occurred repeatedly and were alternately dominant in the lake during the whole research period. Some diatoms were dominant only in limited period, like Cyclotella choctawhatcheeana (evident since 2001), and Pseudo-nitzschia spp. (evident in the period 2002 to 2009). It appears that the interplay of environmental conditions such as variability in thermohaline and redox conditions, nutrient and reduced sulphur concentration influence the phytoplankton development and abundance in the lake.

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Doukari, Michaela, Marios Batsaris, and Konstantinos Topouzelis. "UASea: A Data Acquisition Toolbox for Improving Marine Habitat Mapping." Drones 5, no. 3 (August 3, 2021): 73. http://dx.doi.org/10.3390/drones5030073.

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Unmanned aerial systems (UAS) are widely used in the acquisition of high-resolution information in the marine environment. Although the potential applications of UAS in marine habitat mapping are constantly increasing, many limitations need to be overcome—most of which are related to the prevalent environmental conditions—to reach efficient UAS surveys. The knowledge of the UAS limitations in marine data acquisition and the examination of the optimal flight conditions led to the development of the UASea toolbox. This study presents the UASea, a data acquisition toolbox that is developed for efficient UAS surveys in the marine environment. The UASea uses weather forecast data (i.e., wind speed, cloud cover, precipitation probability, etc.) and adaptive thresholds in a ruleset that calculates the optimal flight times in a day for the acquisition of reliable marine imagery using UAS in a given day. The toolbox provides hourly positive and negative suggestions, based on optimal or non-optimal survey conditions in a day, calculated according to the ruleset calculations. We acquired UAS images in optimal and non-optimal conditions and estimated their quality using an image quality equation. The image quality estimates are based on the criteria of sunglint presence, sea surface texture, water turbidity, and image naturalness. The overall image quality estimates were highly correlated with the suggestions of the toolbox, with a correlation coefficient of −0.84. The validation showed that 40% of the toolbox suggestions were a positive match to the images with higher quality. Therefore, we propose the optimal flight times to acquire reliable and accurate UAS imagery in the coastal environment through the UASea. The UASea contributes to proper flight planning and efficient UAS surveys by providing valuable information for mapping, monitoring, and management of the marine environment, which can be used globally in research and marine applications.

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SK, Jainuddin, Satyanarayana P, and Aruna V.B.K.L. "Multiple targets detection in the marine environment using matlab." International Journal of Engineering & Technology 7, no. 4 (September 17, 2018): 2397. http://dx.doi.org/10.14419/ijet.v7i4.14088.

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This paper implements multiple targets detection against sea clutter by mathematically modeling target as a single point target and sea-clutter as k-distribution model and observing the deterioration in the effective operation of radar using signal processing by matlab. A Variability Index (VI) algorithm is suggested for detection on the basis of constant false-alarm rate (CFAR) property even in heteroge-neous conditions. Comparative analysis of VI-CFAR against various CFAR methods (CA, GO, SO, OS) for multiple targets detection in heterogeneous environment is done in this paper. Comparison and evaluation is done by means of the data which is simulated in MATLAB. The logical operation of the method is verified in heterogeneous condition.

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Wu, Jie, Jing Li, Feng Rao, and Wanzhong Yin. "Characterization of Slag Reprocessing Tailings-Based Geopolymers in Marine Environment." Minerals 10, no. 9 (September 22, 2020): 832. http://dx.doi.org/10.3390/min10090832.

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In this study, copper slag reprocessing tailings (CSRT) were synthesized into geopolymers with 40%, 50% and 60% metakaolin. The evolution of compressive strength and microstructures of CSRT-based geopolymers in a marine environment was investigated. Except for compressive strength measurement, the characterizations of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM) were included. It was found that marine conditions changed the Si/Al ratio in the sodium-aluminosilicate-hydrate (N-A-S-H) gel backbone, promoted the geopolymerization process, led to more Q4(3Al), Q4(2Al) and Q4(1Al) gel formation and a higher compressive strength of the geopolymers. This provided a basis for the preparation of CSRT-based geopolymers into marine concrete.

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Hossen, Amjad, Md Rashel Mahmud, Md Abusina Islam, Syed Kamrul Ahsan, and Md Ibrahim H Mondal. "Minimization of corrosion in aquatic environment – a review." International Journal of Hydrology 7, no. 1 (January 16, 2023): 9–16. http://dx.doi.org/10.15406/ijh.2023.07.00334.

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Corrosion is the gradual deterioration of a material through an electro-chemical reaction with its environment. Electrochemical conditions can be created at the film’s base by bacterial film and salt water of marine environment acts as electrolyte according to the marine science. While corroding, dissolved oxygen and other species as well as the metal surfaces pH can be impact electrochemical process on the metal, which in turn affects. To overcome this problem, there are several methods of preventing a material from corroding. Among them, cathodic protection (CP) and coatings are very popular and effective methods for marine corrosion protection that can provide very good protection over a long period of time. Developing anticorrosive additives that are more effective than the conventional inorganic pigments currently used in paint, may have adverse impacts on environment and human health. In this study, we have focused on cathodic protection (CP) and coatings and the combination of them for providing good protection over a long period.

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Ferretti, Roberta, Massimo Caccia, Massimo Coltorti, and Roberta Ivaldi. "New Approaches for the Observation of Transient Phenomena in Critical Marine Environment." Journal of Marine Science and Engineering 9, no. 6 (May 26, 2021): 578. http://dx.doi.org/10.3390/jmse9060578.

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This paper focuses on the development of new approaches to observe transient phenomena in critical marine environments using autonomous marine vehicles (AMVs) for the acquisition of physical and biogeochemical parameters of water and seabed characterization. The connection with metrological principles, together with the adoption of observing methodologies adjustable according to the specific marine environment being studied, allows researchers to obtain results that are reliable, reproducible, and comparable with those obtained through the classic monitoring methodologies. Tests were executed in dramatically dynamic, sensitive, and fragile areas, where the study and application of new methodologies is required to observe phenomena strongly localized in space and requiring very high resolutions, in time. Moreover, the harsh environmental conditions may present risks not only for the quality and quantity of the acquired data but also for the instrumentation and the operators. This is the case, for instance, in polar marine environments in proximity of tidal glaciers and in the Mediterranean Sea in areas characterized by seabed degassing activities, where AMV-supported monitoring procedures can allow for the safe observation of not repeatable and not completely predictable events.

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Pommier, Thomas, Emmanuel J. P. Douzery, and David Mouillot. "Environment drives high phylogenetic turnover among oceanic bacterial communities." Biology Letters 8, no. 4 (January 18, 2012): 562–66. http://dx.doi.org/10.1098/rsbl.2011.0990.

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Although environmental filtering has been observed to influence the biodiversity patterns of marine bacterial communities, it was restricted to the regional scale and to the species level, leaving the main drivers unknown at large biogeographic scales and higher taxonomic levels. Bacterial communities with different species compositions may nevertheless share phylogenetic lineages, and phylogenetic turnover (PT) among those communities may be surprisingly low along any biogeographic or environmental gradient. Here, we investigated the relative influence of environmental filtering and geographical distance on the PT between marine bacterial communities living more than 8000 km apart in contrasted abiotic conditions. PT was high between communities and was more structured by local environmental factors than by geographical distance, suggesting the predominance of a lineage filtering process. Strong phenotype-environment mismatches observed in the ocean may surpass high connectivity between marine microbial communities.

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Zhu, Ming Yi, and Tao Guo. "Study on Conditions of Over-the-Horizon Detection Basing on Evaporation Duct." Advanced Materials Research 462 (February 2012): 487–91. http://dx.doi.org/10.4028/www.scientific.net/amr.462.487.

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The highest frequency duct is evaporation duct under marine atmospheric environment, and it is a special method of expanding the radar measuring range by using the evaporation duct to achieve the over-the-horizon detection. On what conditions to ensure the realization of the over-the-horizon radar detection is one of key problems. Many aspects, such as evaporation duct discrimination, radar working wavelength and frequency, initial launching angle and the location of radar are studied to get the necessary conditions of the over-the-horizon radar detection. The results show that the four kinds of necessary conditions must meet at the same time instead of only one certain condition, which lays a necessary foundation for the marine radar, ship radar and communication system to exert the largest effects in the evaporation duct environment.

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Faganeli, Jadran, and Nives Ogrinc. "Oxic - anoxic transition of benthic fluxes from the coastal marine environment (Gulf of Trieste, northern Adriatic Sea)." Marine and Freshwater Research 60, no. 7 (2009): 700. http://dx.doi.org/10.1071/mf08065.

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The influence of O2 concentration on mineralisation processes was examined by sediment incubation experiments under controlled laboratory conditions over a sequence of oxic, anoxic and then reoxidising conditions. Sediments were studied from five locations representing marine, lagoonal and brackish environments in the Gulf of Trieste (northern Adriatic Sea). A complete depletion of dissolved O2 and nitrate were observed after ~6 –15 days in marine and lagoonal sediments, and after 5 days in brackish sediments. During the reoxygenation phase, nitrification occurred at some sites, as evidenced by increases in NO3– concentrations, but not at other sites, indicating an inhibited recovery response to intermittent oxic conditions. NH4+ and PO43– regeneration during mineralisation was much more extensive in sediments overlain by oxygen-depleted waters, driving additional eutrophication. During reoxygenation, an influx of phosphate was observed in all three sedimentary environments, removing soluble phosphorus through coagulation and finally precipitation. Two degraded organic matter (OM) types could be distinguished: OM degraded under oxic conditions in marine and brackish sediments v. OM rapidly degraded under anoxic conditions in lagoon sediments.

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Oterkus, Erkan. "Applications of Peridynamics in Marine Structures." Sustainable Marine Structures 4, no. 1 (January 6, 2022): 13. http://dx.doi.org/10.36956/sms.v4i1.475.

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Marine environment is a harsh and challenging environment for both operators and analysers due to extreme weather conditions. As a result of these conditions, marine structures are subjected to extreme and/or cyclic loadings. This will then lead to various different damage modes including corrosion and fatigue. Such damage modes are major threats to the reliability and integrity of marine structures which can cause risk on human and environmental safety, and yield financial losses. Moreover, climate change is a major concern which requires urgent attention. In order to minimize the negative effects of climate change, energy transition from utilisation of fossil fuels to greener energy solutions, such as offshore wind, should be adapted. There is currently a rapid progress on investment on green technologies especially offshore wind energy generation. Another emerging area is hydrogen which is considered as the environmentally friendly fuel of the future.

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Huang, Liwen, Yingfan Chen, Lei Wu, Cheng Xie, and Shuzhe Chen. "Research on Uncertainty Evolution of Ship Collision Status Based on Navigation Environment." Journal of Marine Science and Engineering 10, no. 11 (November 13, 2022): 1741. http://dx.doi.org/10.3390/jmse10111741.

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There is a need to study the evolutionary laws of the risks in the navigation environments of complex marine areas. This can promote shipping safety using an early-warning system. The present study determines shipping flows and meteorological conditions in a marine area on the basis of meteorological and automatic identification system (AIS) data. It also determines the uncertainty evolution law of the navigation environment’s influencing factors. Moreover, a navigation risk evolution system for ships in complex marine areas was developed. A case study was carried out in a coastal area of China on the basis of the determined evolutionary laws. Evolution in the navigational environment risk within the case study area was analyzed. The results showed that the hydrometeorology wind factor has the greatest impact on the risk of ship collisions. This work was not only able to show advances in navigational collision environmental evolution laws but also provides a theoretical reference for the evaluation and early warning of risks in shipping environments.

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Doukari, Michaela, Stelios Katsanevakis, Nikolaos Soulakellis, and Konstantinos Topouzelis. "The Effect of Environmental Conditions on the Quality of UAS Orthophoto-Maps in the Coastal Environment." ISPRS International Journal of Geo-Information 10, no. 1 (January 6, 2021): 18. http://dx.doi.org/10.3390/ijgi10010018.

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Marine conservation and management require detailed and accurate habitat mapping, which is usually produced by collecting data using remote sensing methods. In recent years, unmanned aerial systems (UAS) are used for marine data acquisition, as they provide detailed and reliable information through very high-resolution orthophoto-maps. However, as for all remotely sensed data, it is important to study and understand the accuracy and reliability of the produced maps. In this study, the effect of different environmental conditions on the quality of UAS orthophoto-maps was examined through a positional and thematic accuracy assessment. Selected objects on the orthophoto-maps were also assessed as to their position, shape, and extent. The accuracy assessment results showed significant errors in the different maps and objects. The accuracy of the classified images varied between 2.1% and 27%. Seagrasses were under-classified, while the mixed substrate class was overclassified when environmental conditions were not optimal. The highest misclassifications were caused due to sunglint presence in combination with a rough sea-surface. A change detection workflow resulted in detecting misclassifications of up to 45%, on orthophoto-maps that had been generated under non-optimal environmental conditions. The results confirmed the importance of optimal conditions for the acquisition of reliable marine information using UAS.

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Al-Muzaini, S., O. Samhan, and M. F. Hamoda. "Sewage-Related Impact on Kuwait's Marine Environment – A Case Study." Water Science and Technology 23, no. 1-3 (January 1, 1991): 181–89. http://dx.doi.org/10.2166/wst.1991.0414.

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This paper overviews the marine environmental impacts associated with Kuwait's liquid wastes, whose volume has grown considerably over the last two decades and is expected to grow further. The characteristics of local sewage, its collection, handling and treatment practices, and routes of input into the local marine environment are described. Realized or potential environmental impacts are discussed. Sewage discharge has been found to exert different impacts on Kuwait's marine environment, ranging from fish kills and localized smothering of benthic organisms and microbial pollution to potential wider impacts on overall marine productivity. These impacts are due to a combination of unique local environmental conditions (e.g., high ambient air temperatures, high rates of dust fallout and creeping sands, and prevalence of wide intertidal flats) and specific problems in the sewage works (high strength and anaerobicity of sewage, lack of alternative routes from peripheral pumping stations to a central treatment plant that is biochemically overloaded, emergency discharge through short outfalls onto wide intertidal flats, and discharges from premises that are not connected to a sewerage scheme). Recommendations to alleviate these impacts are summarized.

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Bacosa, Hernando Pactao, Sheila Mae B. Ancla, Cris Gel Loui A. Arcadio, John Russel A. Dalogdog, Dioniela Mae C. Ellos, Heather Dale A. Hayag, Jiza Gay P. Jarabe, et al. "From Surface Water to the Deep Sea: A Review on Factors Affecting the Biodegradation of Spilled Oil in Marine Environment." Journal of Marine Science and Engineering 10, no. 3 (March 15, 2022): 426. http://dx.doi.org/10.3390/jmse10030426.

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Over the past century, the demand for petroleum products has increased rapidly, leading to higher oil extraction, processing and transportation, which result in numerous oil spills in coastal-marine environments. As the spilled oil can negatively affect the coastal-marine ecosystems, its transport and fates captured a significant interest of the scientific community and regulatory agencies. Typically, the environment has natural mechanisms (e.g., photooxidation, biodegradation, evaporation) to weather/degrade and remove the spilled oil from the environment. Among various oil weathering mechanisms, biodegradation by naturally occurring bacterial populations removes a majority of spilled oil, thus the focus on bioremediation has increased significantly. Helping in the marginal recognition of this promising technique for oil-spill degradation, this paper reviews recently published articles that will help broaden the understanding of the factors affecting biodegradation of spilled oil in coastal-marine environments. The goal of this review is to examine the effects of various environmental variables that contribute to oil degradation in the coastal-marine environments, as well as the factors that influence these processes. Physico-chemical parameters such as temperature, oxygen level, pressure, shoreline energy, salinity, and pH are taken into account. In general, increase in temperature, exposure to sunlight (photooxidation), dissolved oxygen (DO), nutrients (nitrogen, phosphorous and potassium), shoreline energy (physical advection—waves) and diverse hydrocarbon-degrading microorganisms consortium were found to increase spilled oil degradation in marine environments. In contrast, higher initial oil concentration and seawater pressure can lower oil degradation rates. There is limited information on the influences of seawater pH and salinity on oil degradation, thus warranting additional research. This comprehensive review can be used as a guide for bioremediation modeling and mitigating future oil spill pollution in the marine environment by utilizing the bacteria adapted to certain conditions.

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Pisera, Andrzej, Klaus Rützler, Józef Kaz'mierczak, and Stephan Kempe. "Sponges in an extreme environment: suberitids from the quasi-marine Satonda Island crater lake (Sumbawa, Indonesia)." Journal of the Marine Biological Association of the United Kingdom 90, no. 1 (November 3, 2009): 203–12. http://dx.doi.org/10.1017/s0025315409990968.

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Sponges are rare in extreme environments, and very little is known about their adaptations to such settings. Evidence from two species in a marine-derived midwater stratified crater lake on Satonda Island (Sumbawa, Indonesia) suggests their production of gemmules (resting bodies), a rare trait in marine sponges but common in freshwater forms, may be a survival mechanism in the lake's harsh environment. With its epilimnion hydrochemistry—characterized by changing alkalinity, salinity, and O2 levels over the region's wet and dry seasons—the lake sustains only a few marine macroscopic organisms, among them the suberitid sponges Protosuberites lacustris comb. nov. and Suberites sp. (Hadromerida: Suberitida). Both species belong to the same group as sponges reported from other marine-derived lakes with strongly varying and extreme environmental (especially chemical) parameters. The morphological characters, taxonomic position, ecological adaptations, environmental conditions, and biota associated with the sponges in this ecologically unique site are presented here.

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Byun, Byungseol and 전하나. "Analysis of the Actual Conditions about Managing Marine Environment at Island Areas in Incheon." Journal of the Economic Geographical Society of Korea 11, no. 4 (December 2008): 618–30. http://dx.doi.org/10.23841/egsk.2008.11.4.618.

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Toumi, Arwa, Chokri Boubahri, Jalel Briki, Haythem Barrek, and Ahmed Hichem Hamzewi. "HSLA Naval Grade Steel Failure Investigation in Marine Environment Under Ship Hull Operational Conditions." Journal of Failure Analysis and Prevention 21, no. 6 (November 10, 2021): 2224–33. http://dx.doi.org/10.1007/s11668-021-01276-7.

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Wang, Yanbin, and Deli Gao. "Study on the marine environment limiting conditions of deepwater drilling for natural gas hydrate." Applied Energy 312 (April 2022): 118802. http://dx.doi.org/10.1016/j.apenergy.2022.118802.

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41

Hossain, Sushmita, Takashi Ishiyama, Shoichi Hachinohe, and Chiaki T. Oguchi. "Leaching Behavior of As, Pb, Ni, Fe, and Mn from Subsurface Marine and Nonmarine Depositional Environment in Central Kanto Plain, Japan." Geosciences 9, no. 10 (October 8, 2019): 435. http://dx.doi.org/10.3390/geosciences9100435.

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The leaching behavior of arsenic (As), lead (Pb), nickel (Ni), iron (Fe), and manganese (Mn) was investigated from subsurface core sediment of marine and nonmarine depositional environments in central Kanto Plain, Japan. A four-step sequential extraction technique was adopted to determine the chemical speciation, potential mobility, and bioavailability of metals under natural conditions in variable depositional environments. In addition, a correlation of these properties with pore water and total metal content was carried out. The concentration of As in pore water was found to be 2–3 times higher than the permissible limit (10 µg/L) for drinking water and leachate in fluvial, transitional, and marine environments. The trend of potential mobile fractions of As, Pb, and Ni showed Fe–Mn oxide bound > carbonate bound > ion exchangeable bound > water soluble in the fluvial environment. However, in the marine environment, it showed Fe–Mn oxide bound > water soluble > carbonate bound > ion exchangeable bound for As. The leaching of As in this fluvial environment is due to the organic matter-mediated, reductive dissolution of Fe–Mn oxide bound, where Mn is the scavenger. The amount of total content of As and sulfur (S) in transitional sediment reflects an elevated level of leachate in pore water, which is controlled by S reduction. However, the leaching of As in marine sediment is controlled by pH and organic matter content.

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Choi, Yoo Youl, and Myung Hyun Kim. "Corrosion behaviour of welded low-carbon steel in the Arctic marine environment." RSC Advances 8, no. 53 (2018): 30155–62. http://dx.doi.org/10.1039/c8ra05371e.

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Rodwell, Lynda D., and Callum M. Roberts. "Fishing and the impact of marine reserves in a variable environment." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 11 (November 1, 2004): 2053–68. http://dx.doi.org/10.1139/f04-142.

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We use discrete-time models to investigate the impact of marine reserve establishment on fishery catch and biomass levels in open-access and quota-regulated fisheries under conditions of recruitment variability and natural mortality events. We find that under the conditions of variability tested, reserves can increase the probability of achieving target levels of biomass (60%, 35%, and 5% of carrying capacity) and can reduce catch variability in neighbouring fisheries, making future planning in the fishery more efficient. The size of the reserve required to meet each objective will depend on the initial condition of the stock and the exploitation rate in the fishery. Reserve coverage of between 20% and 40% prevent stock collapse in most cases. In heavily exploited fisheries, reserves are also likely to enhance mean catches, particularly in highly variable systems. If the stock has previously been heavily exploited, large reserves (≥60%) may be required to significantly increase the probability of achieving target biomass levels. However, once stocks have recovered, reserve coverage may be reduced without a reduction in this probability of success.

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44

Nguyen Hong Duc, Paul, Dorian Cazau, Paul R. White, Odile Gérard, Joël Detcheverry, Frank Urtizberea, and Olivier Adam. "Use of Ecoacoustics to Characterize the Marine Acoustic Environment off the North Atlantic French Saint-Pierre-et-Miquelon Archipelago." Journal of Marine Science and Engineering 9, no. 2 (February 9, 2021): 177. http://dx.doi.org/10.3390/jmse9020177.

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Visual observations of the marine biodiversity can be difficult in specific areas for different reasons, including weather conditions or a lack of observers. In such conditions, passive acoustics represents a potential alternative approach. The objective of this work is to demonstrate how information about marine biodiversity can be obtained via detailed analysis of the underwater acoustic environment. This paper presents the first analysis of the Saint-Pierre-and-Miquelon (SPM) archipelago underwater acoustic environment. In order to have a better knowledge about the marine biodiversity of SPM, acoustic recordings were sampled at different time periods to highlight seasonal variations over several years. To extract information from these acoustic recordings, standard soundscape and ecoacoustic analysis workflow was used to compute acoustic metrics such as power spectral density, third-octave levels, acoustic complexity index, and sound pressure levels. The SPM marine acoustic environment can be divided into three main sound source classes: biophony, anthrophony, and geophony. Several cetacean species were encountered in the audio recordings including sperm whales (which were detected by visual observations and strandings of 3 males in 2014), humpback, and blue whales.

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Li, Wenhao, Zhihuan Zhang, Weiming Wang, Shuangfang Lu, Youchuan Li, and Ning Fu. "Palaeoenvironment and Its Control on the Formation of Miocene Marine Source Rocks in the Qiongdongnan Basin, Northern South China Sea." Scientific World Journal 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/240415.

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The main factors of the developmental environment of marine source rocks in continental margin basins have their specificality. This realization, in return, has led to the recognition that the developmental environment and pattern of marine source rocks, especially for the source rocks in continental margin basins, are still controversial or poorly understood. Through the analysis of the trace elements and maceral data, the developmental environment of Miocene marine source rocks in the Qiongdongnan Basin is reconstructed, and the developmental patterns of the Miocene marine source rocks are established. This paper attempts to reveal the hydrocarbon potential of the Miocene marine source rocks in different environment and speculate the quality of source rocks in bathyal region of the continental slope without exploratory well. Our results highlight the palaeoenvironment and its control on the formation of Miocene marine source rocks in the Qiongdongnan Basin of the northern South China Sea and speculate the hydrocarbon potential of the source rocks in the bathyal region. This study provides a window for better understanding the main factors influencing the marine source rocks in the continental margin basins, including productivity, preservation conditions, and the input of terrestrial organic matter.

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Kontopoulos, Nikolaos, and Avraam Zelilidis. "Depositional processes in outer arc marginal sib-basins during the Messinian time; Messinian crisis: An example from western Crete Island, Greece." Geologica Balcanica 27, no. 1-2 (August 30, 1997): 91–10. http://dx.doi.org/10.52321/geolbalc.27.1-2.91.

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The ratio of sea-level falling rate to subsidence/uplift rate was the master factor controlling the evolution of three adjacent marginal sub-basins, the Platanos, Kastelli and Maleme Sub-Basins. During the Messinian, the Platanos Sub-Basin was characterized by a constant shelf environment with a water depth of deposition not more than 50 m; a sabkha environment which changed during the latest Messinian to a shelf environment characterized the Kastelli Basin, representing a water depth of deposition changing from 0 m to less than 50 m; fmally, a terrestrial environment which changed during the latest Messinian to a shallow marine environment, characterized the Maleme Basin, representing a sea-level rise of no more than 50 m. The evolution of the depositional environments in the three adjacent basins suggests: a. A total sea-level fall of >250 m from latest Tortonian to latest Messinian time in the western Crete (>200 m during latest Tortonian and 50 m during Early Messinian). b. When the ratio of sea-level falling rate to subsidence/uplift rate is > 1, lake or shallow marine environments (shelf) changed to terrestrial, and outer slope environments changed to shelf environment. When the ratio is slightly > 1 a shelf environment changes to a sabkha; and when it equals 1, the depositional environment changes from a sabkha or terrestrial to shelf environment. c. Depositional environments characterized by lowstand conditions during the Messinian time.

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Dashtgard, Shahin E., Ludvig Löwemark, Pei-Ling Wang, Romy A. Setiaji, and Romain Vaucher. "Geochemical evidence of tropical cyclone controls on shallow-marine sedimentation (Pliocene, Taiwan)." Geology 49, no. 5 (January 26, 2021): 566–70. http://dx.doi.org/10.1130/g48586.1.

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Abstract Shallow-marine sediment typically contains a mix of marine and terrestrial organic material (OM). Most terrestrial OM enters the ocean through rivers, and marine OM is incorporated into the sediment through both suspension settling of marine plankton and sediment reworking by tides and waves under fair-weather conditions. River-derived terrestrial OM is delivered year-round, although sediment and OM delivery from rivers is typically highest during extreme weather events that impact river catchments. In Taiwan, tropical cyclones (TCs) are the dominant extreme weather event, and 75% of all sediment delivered to the surrounding ocean occurs during TCs. Distinguishing between sediment deposited during TCs and that redistributed by tides and waves during fair-weather conditions can be approximated using δ13Corg values and C:N ratios of OM. Lower Pliocene shallow-marine sedimentary strata in the Western Foreland Basin of Taiwan rarely exhibit physical evidence of storm-dominated deposition. Instead they comprise completely bioturbated intervals that transition upward into strata dominated by tidally generated sedimentary structures, indicating extensive sediment reworking under fair-weather conditions. However, these strata contain OM that is effectively 100% terrestrial OM in sediment that accumulated in estimated water depths <35 m. The overwhelming contribution of terrestrially sourced OM is attributed to the dominance of TCs on sedimentation, whereby ∼600,000 TCs are estimated to have impacted Taiwan during accumulation of the succession. In contrast, the virtual absence of marine OM indicates that organic contributions from suspension settling of marine OM is negligible regardless of the preserved evidence of extensive reworking under fair-weather conditions. These data suggest that (1) even in the absence of physical expressions of storm deposition, TCs still completely dominate sedimentation in shallow-marine environments, and (2) the organic geochemical signal of preserved shallow-marine strata is not reflective of day-to-day depositional conditions in the environment.

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Moura, William, João Carlos Araujo, Thales Lucio, and João Adauto Souza Neto. "PALEOAMBIENTE DEPOSICIONAL E ORIGEM DA MATÉRIA ORGÂNICA DOS FOLHELHOS BETUMINOSOS DA FORMAÇÃO IPUBI, PORÇÕES LESTE E SUDESTE DA BACIA DO ARARIPE, NE DO BRASIL: EVIDÊNCIA DE N-ALCANOS E ISOPRENOIDES." Estudos Geológicos 30, no. 1 (December 17, 2020): 31–44. http://dx.doi.org/10.18190/1980-8208/estudosgeologicos.v30n1p31-44.

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Paleoenvironmental conditions from cretaceous black shales of Ipubi Formation (Araripe Basin-NE Brasil) are continuously debated. The main point of controversy is if these rocks were deposited in a lacustrine or restricted marine environment. The present study was developed in these black shales, by saturated biomarkers analyses (n-alkanes and isoprenoids) to discuss about the paleoenvironment of deposition of those shales. The n-alkanes predominance between n-C13 and n-C19 reveal algalic contribution. However an influence of terrestrial organism is also observed by the presence of n-C27, n-C28, and n-C29. The Pr/Ph ratio and Pr/Ph vs. (Pr+n-C17)/(Fi+n-C18) diagram indicated both anoxic and hypersaline conditions during the deposition of those shales. The Pr/n-C17 vs. Ph/n-C18 diagram also suggests reducing conditions, and classify an algalic contribution as marine-transitional source. Thus, this study indicates that the investigated shales were deposited in reducing and hypersaline conditions in a restricted marine to transitional environment.

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Orazbayеv, Batyr, Saya Santeyeva, Ainur Zhumadillayeva, Kanagat Dyussekeyev, Ramesh K. Agarwal, Xiao-Guang Yue, and Jiangchuan Fan. "Sustainable Waste Management Drilling Process in Fuzzy Environment." Sustainability 11, no. 24 (December 7, 2019): 6995. http://dx.doi.org/10.3390/su11246995.

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Sustainable management issues of waste during drilling oil wells in marine conditions, the process of disposal of drill cuttings in the conditions of deficiency, and fuzzy initial information using fuzzy inference system are investigated. Based on the conducted system analysis, the main criteria for controlling the process of re-injection of suspended drill cuttings were analyzed and selected. We described the technology of preparation and injection of drill cuttings slurry into the underground horizon. The method of modeling and management of the process of disposal of drilling cuttings in the marine environment in a fuzzy environment with the use of fuzzy inference system, which helps to overcome the problems of scarcity and fuzziness of the original information due to the knowledge and experience of experts are proposed. The scheme and structure of the elements of the fuzzy inference system based on the Mamdani algorithm are given. The implementation of the fuzzy output system procedure was carried out in MatLab using Fuzzy Logic Toolbox. For the purpose of sustainable waste management in the process of oil production of marine fields, waste management tasks are formulated as a fuzzy mathematical programming problem, which takes into account economic and environmental criteria and many production constraints that may be fuzzy. Since the vector of such criteria is characterized by inconsistency, the developed methods for solving the set tasks of sustainable management are based on various tradeoff schemes modified to work in a fuzzy environment. The novelty and originality of the developed methods lies in the fact that, unlike the well-known methods of similar methods for solving fuzzy problems, they are set and solved without conversion to a system of equivalent deterministic problems, with-out losing the main part of the collected fuzzy information. This allows, through the full use of the original fuzzy information, to obtain a more adequate solution to the fuzzy problem of the real problem under production conditions.

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Vavrdová, Milada, and Jiřina Dašková. "Middle Devonian palynomorphs from southern Moravia: an evidence of rapid change from terrestrial deltaic plain to carbonate platform conditions." Geologica Carpathica 62, no. 2 (April 1, 2011): 109–19. http://dx.doi.org/10.2478/v10096-011-0010-2.

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Middle Devonian palynomorphs from southern Moravia: an evidence of rapid change from terrestrial deltaic plain to carbonate platform conditions Dispersed fossil miospores and acritarchs have been recovered from the subsurface pelites in the Uhřice-1 borehole, southern Moravia. Spores of ferns, sphenopsids and lycopods with rare marine microplankton (acritarchs and chitinozoans) cysts indicate a predominantly continental environment with a limited marine influence. Dispersed miospores with cysts of unicellular marine microplankton confirm the Middle Devonian, most probably early Givetian (AD lem) age of marine transgression in southern Moravia. Thermal alteration of palynomorphs shows average values, with TAI ranging from 2+ to 3+, corresponding to 60-70 °C.

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Journal articles on the topic 'Marine environment conditions'

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