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The International Sirius Mathematics Center, located on the Black Sea coast, was founded in 2019 by the Talent and Success Foundation for organizing mathematical conferences and other events promoting the development of mathematics in Russia. In 2024, the Center has acquired its own Russian-language journal for publication of original research papers by participants of conferences held at the Center. The authors are invited to submit papers to the journal at https://ef.msp.org/submit/sirius [ABSTRACT FROM AUTHOR]

Mangroves are ecosystems that grow in the intertidal areas of coastal zones, playing crucial ecological roles and possessing unique economic and social values. They have garnered significant attention and research interest. Semantic segmentation of mangroves is a fundamental step for further investigations. However, mangrove remote sensing images often have large dimensions, with a substantial portion of the image containing mangrove features. Deep learning convolutional kernels may lead to inadequate receptive fields for accurate mangrove recognition. In mangrove remote sensing images, various challenges arise, including the presence of small and intricate details aside from the mangrove regions, which intensify the segmentation complexity. To address these issues, this paper primarily focuses on two key aspects: first, the exploration of methods to achieve a large receptive field, and second, the fusion of multi-scale information. To this end, we propose the Multi-Scale Fusion Attention Network (MSFANet), which incorporates a multi-scale network structure with a large receptive field for feature fusion. We emphasize preserving spatial information by integrating spatial data across different scales, employing separable convolutions to reduce computational complexity. Additionally, we introduce an Attention Fusion Module (AFM). This module helps mitigate the influence of irrelevant information and enhances segmentation quality. To retain more semantic information, this paper introduces a dual channel approach for information extraction through the deep structure of ResNet. We fuse features using the Feature Fusion Module (FFM) to combine both semantic and spatial information for the final output, further enhancing segmentation accuracy. In this study, a total of 230 images with dimensions of 768 pixels in width and height were selected for this experiment, with 184 images used for training and 46 images for validation. Experimental results demonstrate that our proposed method achieves excellent segmentation results on a small sample dataset of remote-sensing images, with significant practical value. This paper primarily focuses on three key aspects: the generation of mangrove datasets, the preprocessing of mangrove data, and the design and training of models. The primary contribution of this paper lies in the development of an effective approach for multi-scale information fusion and advanced feature preservation, providing a novel solution for mangrove remote sensing image segmentation tasks. The best Mean Intersection over Union (MIoU) achieved on the mangrove dataset is 86%, surpassing other existing models by a significant margin. [ABSTRACT FROM AUTHOR]

This paper documents the occurrence of the genus Umbilicaria in the Argentine Islands–Kyiv Peninsula region of the Graham Coast in the maritime Antarctic. The presence of seven Umbilicaria species (U. africana, U. antarctica, U. aprina, U. decussata, U. kappenii, U. nylanderiana and U. umbilicarioides) in the ice-free areas of the Argentine Islands–Kyiv Peninsula region were confirmed. The species of U. africana and U. aprina are documented from the studied region for the first time. This study moves the southern distribution limit of U. africana about 300 km to the south: to the Argentine Islands–Kyiv Peninsula region. The distribution maps of Umbilicaria species for the studied region and maritime Antarctica are prepared. [ABSTRACT FROM AUTHOR]

The present paper aimed to assess the sediment distribution pattern, mode of transport, and its interaction with hydrodynamic and topographic conditions at different depths and regions along the east coast of India. About 900 surficial sediment samples were collected and analysed on a monthly basis for the Chennai coastal region at 32 stations from 2013 to 2015. The study region is classified into four types, such as beach, inlet, 5 m, and 10 m depth. Sediment textural and grain size trend analyses were conducted to achieve the objectives. Sediment characteristics for the region were recorded as sandy, equally dominated by unimodal and bimodal at the beach, while unimodal at shallow depths (5 and 15 m). The sediments were medium sand to coarse sand at the beach, mostly fine followed by medium at 5 and 15 m depths. The sediment sorting is dominated by moderately well-sorted sediments; the skewness of beach sediments was negative, while nearshore sediments were found positive; average kurtosis values of sediments were noticed to be mesokurtic. The CM plot depicts that the sediments were mostly derived by tractive current, and the modes of transport are "bottom suspension and rolling" and "graded suspension no rolling" at beach locations and shallow water depths, respectively. The GSTA analysis reveals the annual average sediment transport pattern is northerly. The numerical hydrodynamic study confirms the GSTA and CM plot analysis. The study reveals a stable sedimentary environment south of the Chennai port and instability in the northern part. The study includes large spatiotemporal nearshore sediment data with hydrodynamic conditions, immensely helpful to coastal stakeholders and researchers. [ABSTRACT FROM AUTHOR]

Improving the living conditions of campo residents requires access to drinking water. The surface and subsurface factors of a region influence the groundwater potential zones. The main objectives of this paper are to identify suitable groundwater zones for productive drilling and to assess groundwater mineralization in the coastal aquifers of the study area. Geographic Information Systems (GIS) and Analytical Hierarchy Process (AHP) were used in the methodology to generate the groundwater potential map. Lithology, geomorphology, specific capacity, hydraulic conductivity, transmissivity, rainfall, infiltration rate, lineament density, drawdown, static water level, soil thickness, drainage density, slope, and land use/land cover were taken into account to characterize the groundwater potential zones. Weights were assigned to the various parameters and their characteristics according to their impact on groundwater recharge. The groundwater potential map of Campo was classified into four zones namely: very low 783.5 km2 (28.9%), low 835.2 km2 (31.9%), moderate 858.4 km2 (31.7%) and high 199.9 km2 (7.3%). Multivariate statistical analysis was used to understand groundwater mineralization. Two phenomena are responsible for the mineralization of water: a process of interaction between water and rock; and a process of salinization resulting from natural phenomena or anthropic activities. The present study could guide hydrogeological investigations and groundwater resource management planning in the study area. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of basic population parameters of the black scorpionfish caught in the waters of the coasts of the Crimean Peninsula, its grown rate, and its nutritional spectrum. The modern food supply of scorpionfish from the southeastern part differs from that in 1940–1950: in the Sevastopol region, scorpionfish mainly consume fish, and in the waters of Feodosia they consume crustaceans. The main changes in food items, depending on the fish age, are associated with the components—decapods and fish. In the southeastern part of Crimea, small fish species predominate in the diet of scorpionfish, which affected the higher growth rate of the object studied. Black scorpionfish at the age of 6 years and older in these waters consume mainly decapods. In Sevastopol waters, the diet does not change significantly depending on age, so the fish component in the stomach of black scorpionfish of older age groups cause it to grow faster. However, no significant differences in the growth rate of fish from the two areas were obtained. The data presented in the paper on the physical and chemical parameters of water, as well as the distribution of bottom aquatic vegetation in the two main study areas, demonstrate small differences in the quality of the environment and are satisfactory for the bottom predator studied. The average age of the scorpionfish from Karadag was 5.9 years old, the most numerous age group was 4 years; the average age of individuals from the water area was 3.72, and the most numerous age group was 3 years. In the Sevastopol region, scorpionfish up to 5 years of age are larger than in the Feodosia region, and from 6 years of age it is the other way around. Despite this, the condition factor of fish from the waters of southeastern Crimea was higher in most cases. [ABSTRACT FROM AUTHOR]

The design flood for a coastal basin based on model simulations can be impacted by various conditions other than design storm, such as tide level. However, the design storm and tide level are usually investigated separately, and the relation between them has not been sufficiently studied, which may have unexpected impacts on model simulations. This paper presents a bivariate assessment framework that aims to evaluate the coordination between design storm and tide level using a copula-based joint distribution to derive the conditional probability of coincidences between design storm and tide level intervals. We apply this framework to the Tai Lake Basin (TLB) in the eastern coast of China and investigate what tide level along its coastline is appropriate for guiding flood control planning. Our findings reveal that the currently-used tide level along the southern coast of TLB is too low and should be raised by approximately 0.35 m and 0.12 m under maximum 1-day and 3-day storms, respectively. Meanwhile, the tide levels for the north and east coasts are appropriate. This paper provides a comprehensive understanding of the interplay between design storm and tide level in a large coastal basin, offering insights into the design of flood protection systems. [ABSTRACT FROM AUTHOR]

Conventionally, volcanic margins have been considered devoid of hydrocarbon, but many discoveries and research in recent past have proved the presence of hydrocarbon prospects within them. However, hydrocarbon exploration within volcanic margin is constrained by seismic imaging. Further, identification of continent to oceanic boundary (COB) is critical to hydrocarbon search as hydrocarbon is found mostly over continental crust. Seaward dipping reflectors, associated with volcano-sedimentary sequences, located along rifted continental margins and represented by highly dipping strong amplitude seismic reflectors, play an important role to study volcanic margins. Keeping in view the problems of hydrocarbon exploration within volcanics, seaward dipping reflectors (SDRs) in Indian context have been studied in detail in this paper. It facilitates mapping of continent-oceanic boundary (COB). It has impact on hydrocarbon prospectivity in volcanic margins as it can provide formidable seal and secondary induced maturity. In India, several discoveries have been made in volcanic margins along west coast, from weathered, fractured basalt and sub-basalt sediments. In the present work, long offset regional seismic data (18 dip lines and 1 cross line), along east coast, have been interpreted. SDRs help in hydrocarbon prospectivity assessment for both discrimination of interbedded sediments and preferential accumulation of hydrocarbon. Mapping of linear features not only helped to demarcate COB but also their presence at 6–10 km depth. For the first time, such comprehensive study on SDRs has been done along Indian peninsular region with indications for hydrocarbon prospectivity at deeper levels along Indian peninsular region. [ABSTRACT FROM AUTHOR]

With economic and societal development, the ecological environment of the Yellow River Delta-Laizhou Bay coastal zone has been seriously damaged. Exploring the changes in land use and ecosystem service value (ESV) is essential to ecological construction of the region. The random forest classification method was used for land cover interpretation of the four periods of remote sensing images in the study area from 1990 to 2020. Newly calculated regional difference coefficients and social development coefficients were used to construct a dynamic ESV assessment model and to study its changes from overall and sea‒land gradient perspectives. The results showed that construction land, salt pans, aquaculture ponds, and inland water masses expanded rapidly, while cropland, tidal flats, and shallow waters shrank sharply over the past 30 years. The ESV in the study area has continued to decrease from 34.47 billion yuan in 1990 to 25.23 billion yuan in 2020, a total decrease of 9.23 billion yuan. This is mostly due to the encroachment of construction land, salt pans, and aquaculture ponds, and the flow of ecosystem services from high-value land cover types (tidal flats, herbaceous wetlands, and cropland) to medium- and low-value land cover types. Moreover, the land cover transfer and ESVs exhibited a decreasing trend from sea to land, with significant sea–land gradient differences. Land conversion is most common in the 0–15 km coastal zone, mainly from natural wetlands to artificial wetlands, where the ESV also decreases rapidly. Considering the regional differences and social development in this paper, the ESV of small-scale areas can be reasonably evaluated to explore the characteristics and causes of changes in land use and ESVs, which can provide an important reference for ecological protection and land use management in the region. [ABSTRACT FROM AUTHOR]

The paper examines the influence of seasonal ice and prevalent type of recharge on the formation and functioning of zoobenthos communities in the coastal shallow zone of water bodies located north of 35° N. It was revealed that in the coastal shallow zone, zoobenthos species do not form communities but are represented by seasonal ephemeral groups. These habitations reach the maximum species diversity and qualitative development in July. Recommendations are given on the frequency of zoobenthos sampling to determine the water quality and an ecological status of a water body. [ABSTRACT FROM AUTHOR]

In Scotland, residents have fought open-net salmon farms and their toll on human and nonhuman bodies for decades. This paper recollects seven years of work in Skye and Raasay, two islands off the northwest coast of the country, developing strategies to divest away from salmon aquaculture. Addressing the contemporary wave of underwater clearances created by UK's top food export industry, it unpacks the implementation of a transition into alternative horizons by embracing the legacies of toxicity inherited from salmon extractivist industries. CLIMAVORE, a framework developed as a research-led artistic practice by the authors, investigates how to eat in the new seasons of the climate crisis. In a season of marine dead zones, it facilitates new approaches to aquaecology and coastal care that cultivate coastal livelihoods. CLIMAVORE began with a new public forum, shaped as a multispecies intertidal table, established in Skye in 2017 to envision environmentally regenerative and socially reparative forms of food production based on metabolic interactions between humans and depleted landscapes that benefit a plethora of species. CLIMAVORE's site responsive methodology relies on a socially-engaged art practice, consisting of fieldwork, interviews, working groups, oral histories, performative meals, cooking and building apprenticeships, tidal gardening, material testing and public art installations. Ongoing collaboration with residents, scientists, and policymakers critically explores ways of living not only on but with the coast. This new holistic approach to coastal nourishment provides methodologies for ecological praxis as well as a platform for researchers and the general public to imagine an alternative ecological future: the tidal commons. [ABSTRACT FROM AUTHOR]

The paper shows that the lower reaches of the Varzuga River (Terskii coast of the White Sea) are subject to a strong effect of sea tides, which can be seen in level variations and the periodic occurrence of reverse (tidal) currents and saltwater intrusions. The data was obtained during the expedition carried out in winter 2020 at the estuary of the Varzuga River along with data collected by the authors at the estuaries of other rivers in the White Sea basin (the Mezen, Onega, Umba, Kyanda, Tamitsa, and Kuzreka rivers) in 2017−2019. In this context, characteristics of the processes mentioned above are given and the factors that affect them (channel relief, river flow, tides, and ice) are discussed. [ABSTRACT FROM AUTHOR]

In the face of current uncertainties about the processes of climate change and its consequences, the search for possible response strategies is urgently needed. One of the most serious repercussions of climate change, which threatens many coastal areas globally, is the sea-level rise. To deepen understanding of this phenomenon and its related impacts, several models have recently been developed to satisfy the unique needs of coastal zone management. These models are very useful because of their visualization and prediction capabilities as they aid in decision-making regarding the adaptation of current protected area investments. This review, therefore, provides evidence of the potential and effectiveness of recent mapping models for managing the effects of sea-level rise. This study examined current models for mapping flood risk areas as a result of sea-level rise. It also provides guidelines to help coastal zone managers and policymakers decide the applicability of various models at local, regional, and global scales. There is no universally accepted model, and each of the models reviewed in this paper has its strengths and weaknesses. However, the models provided by the National Oceanic and Atmospheric Administration are commonly used by organizations and others. These models are more accessible and comprehensible for scientists and individuals with limited scientific background knowledge on sea-level rise. [ABSTRACT FROM AUTHOR]

The world is currently confronting one of its biggest environmental challenges: combating climate change. Coastal zones are one of the areas thought to be most sensitive to current and future climate change threats. The paper integrates Remote Sensing (RS), Geographic Information System (GIS) techniques, and Multi-Criteria Decision Analysis (MCDA) to detect vulnerable areas from climate change impacts in coastal zones in order to recommend adaptation systems in new coastal zones that can withstand various climatic changes. The proposed decision-making framework was developed in three phases: 1) climate data collection and processing; 2) Coastal Climate Impact Assessment (CCIA) model development; and 3) implementation and adaptation system selection. The climate data collection and processing phase involves determining the most significant climate change parameters and their indicators that affect coastal zone stability, extracting climatic data indicators from different climate database sources, and prioritizing the selected indicators. The indicators' weights were estimated using the Analytical Hierarchy Process (AHP) through a questionnaire survey shared with experts in climate change impacts. A CCIA model development phase involves the formulation of the proposed model using GIS technique to discover the vulnerable areas according to the most dominant impact. The implementation and adaptation system selection phase involves the application of the framework to Al-Alamein New City in Egypt. A sensitivity analysis was conducted to measure the behavior of several climate change parameters to identify the most critical parameter for climate change in Al-Alamein New City. The results showed that the geology of the region is the most crucial component influenced by climate change. It is capable of producing a very sensitive area in the coastal zone while also taking other factors into account. When creating new urban neighborhoods, the erosion of the shoreline is the least important factor to consider. This is because coastal deterioration is caused by both the influence of metrological data on the region and the impact of human activity. Shoreline deterioration will be reduced if climate conditions are maintained while limiting the impact of human activities. To adapt to the long-term effects of climate change on coastal zones, a combination of soft and hard protection systems should be considered. [ABSTRACT FROM AUTHOR]

This paper evaluates the NASA Earth Exchange Global Daily Downscaled Projections’ (NEX-GDDP) CMIP6 models’ performance in simulating extreme climate indices across China and its eight subregions for the period 2081–2100 under SSP1-2.6, SSP2-4.5 and SSP5-8.5 scenarios. The models effectively reproduce the spatial patterns of extreme high temperatures, especially in northern China. They show enhanced capabilities in accurately simulating the maximum daily maximum temperature (TXx) and the number of high temperature days (T35). They improve the cold bias of the TXx index in Northwest China and warm bias in South China. In terms of precipitation, the models demonstrate strong performance, evidenced by significant spatial correlations in total wet day precipitation (PTOT) simulations. They reduce the biases of PTOT and simple daily intensity (SDII) compared to CMIP6 models. Regionally, they enhance PTOT accuracy along southern coasts and in Yunnan, better captures very heavy precipitation days (R20) in the Southwest region, max 5-day precipitation (RX5D) in North China and Southwest region, and SDII in the Northeast region and Yunnan. Under SSP5-8.5 scenario, significant impacts include increased TXx in Northwest China, more heatwave days in Southwest China, and more T35 in South China. Extreme precipitation will become more frequent in South and East China, with the greatest intensity increases in Southwest China (SWC1). North China will see fewest consecutive dry days (CDD) indices, while consecutive wet days (CWD) will prominently rise in SWC1. [ABSTRACT FROM AUTHOR]

Microbeads in exfoliating products are a significant source of microplastics entering aquatic ecosystems. This study characterized microbeads in popular facial scrub and body scrub products from Ho Chi Minh City, Vietnam, to quantify abundances and estimate emissions. A selection of facial scrub and body scrub cleansers were collected from local markets and analyzed to quantify microbead properties including the size, color, mass, and abundance of microbeads in the exfoliating cleansers. Results revealed a wide range of microbead sizes (66–1012 μm) and different shapes and colors within and between products. Most contained heterogenous particles of white, green, blue, red, brown, and black spherical microbeads. The range of microbead abundance was 236–942 particles per gram of product. Annual microbead emissions from the use of these products in Ho Chi Minh City were estimated based on population and usage data. The total annual emission of microbeads from facial and body scrubs in Ho Chi Minh City amounted to 1.3 billion microbeads. On a per capita basis, this equaled 880 microbeads per person annually discharged into the local water environment. According to the study, a preliminary calculation indicated that approximately 2640 microbeads were released per year per female student in Ho Chi Minh City. By providing an initial ssessment of microbead pollution arising specifically from personal care items in Vietnam, this study raises awareness of microplastics introduction into Asian coastal zones via cosmetic products. The baseline data establishes a foundation for further investigations. This represents an important step in quantifying and addressing an emerging microplastic source in the region. [ABSTRACT FROM AUTHOR]

Background: Conventional munition dumped into the North Sea and the Baltic Sea close to the German coastline is corroding. A major concern is that biota, including fish, are negatively affected by toxic explosives leaking into marine environments. With the present study, we investigated fish living in close proximity to munition dumping sites for contamination and for signs of health impairments. The flat fish species common dab (Limanda limanda) was used as a model, since it lives in the vicinity of dumping sites and exhibits minor migratory activity. Since explosives are excreted via the bile, the bile fluids from dab were analysed. Further on we inspected the health status of the fish. Results: Dab caught in German coastal waters of the Baltic Sea and the North Sea were contaminated with explosives. Probably due to rapid metabolization, concentrations of the explosive 2,4,6-trinitrotoluene (TNT) were always below limit of detection, but its metabolites 2-amino-4,6-dinitrotoluene and 4-amino-2,6-dinitrotoluene were detected in bile fluid up to 26.36 ng/ml and 95.91 ng/ml, respectively. Only few fish from the Baltic Sea were positive for the explosive HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine with a maximum concentration of 0.89 ng/ml. Highest concentrations of TNT metabolites in bile fluid were detected in dab collected near the dumping site "Kolberger Heide" in the bay of Kiel (Baltic Sea). However, also dab from the North Sea were significantly contaminated with TNT metabolites. Conclusions: The present study showed for the first time that fish living close to near shore munition dumping sites in the North Sea are contaminated with explosives. Various health indicators (body condition factors, externally visible fish diseases, parasites or liver anomalies) showed differences in health status between fish living in the North Sea and in the Baltic Sea, respectively. However, the health status of fish caught at the most contaminated site in the Baltic Sea was not worse compared to fish living in less contaminated areas. We conclude that fish living in the vicinity of dumping sites in the North Sea and the Baltic Sea can be significantly contaminated with explosives. However, obvious health impairments of the fish were not observed. [ABSTRACT FROM AUTHOR]

The northern coastal zone of Taizhou spans three tectonic units: the North China Block, Lower Yangtze Block, and Cathaysian Block. The regional geological structure is complex, magmatic activity is strong, and faults are developed. Based on the latest aeromagnetic data, along with airborne gravity, regional geology, and measured rock susceptibility data, the aeromagnetic anomaly characteristics and distribution regularity of magmatic rocks and faults in the study area are classified and studied. Hundreds of intrusive and volcanic rocks are delineated, and magmatic activity is mainly concentrated in the Meso-Cenozoic Era, which is dominated by the Yanshanian Period and controlled by deep-large faults; these deep-large faults are mainly distributed in NE, NNE, and NW directions. There are SN, EW, and arc faults as well. The former has a great influence on the regional structure and tectonic evolution. Based on the epicenter distribution of natural earthquakes, deep-large fault activity is preliminarily discussed. The results presented in this study can provide a reference for meeting national strategic needs and conducting a comprehensive geological survey of the coastal zone, resolving major geological problems, realizing the goal of land-sea integration, and assisting in the planning of northern coastal economic zone, urban agglomeration planning and site selection, major engineering constructions, and so on. [ABSTRACT FROM AUTHOR]

Island archaeology is a well-established field within the wider discipline, but African contributions to it remain scarce. The Canary Islands are unusual in the broader African context for their relatively long history of occupation (~2000 years) and the intensity with which archaeological research has been, and is, undertaken there. Much of that research, however, has focused on specifically Canarian issues, including efforts to demonstrate connections between the islands' initial settlement and the Classical Mediterranean world. Relatively little of it has been conducted within the broader comparative framework that an island archaeology perspective provides. Additionally, much of the Canarian literature is not directly accessible to non-Hispanophones. In response, I synthesize what is currently known about the archaeology of the Canary Islands, focusing on determining when, how, and by whom they were first settled; the impacts of human settlement on their environments; inter-island variability in precolonial subsistence, social, and political trajectories; and the record left by European contact and subsequent colonization, which began in the 14th century AD. As well as pointing to further opportunities for research within the archipelago, I simultaneously map out several areas where archaeological work there could contribute to wider debates in island archaeology as a whole. [ABSTRACT FROM AUTHOR]

Despite the growing focus in coastal conservation practice toward scientific evidence-based decision-making, there remains a need for enhancing knowledge management and its implication in coastal management planning. In this review manuscript, bibliometric analysis in conjunction with network analysis is used to describe qualitatively and quantitatively the progress, trends and hot spots of coastal science in Moroccan Atlantic coast. In total, 4891 publications from 1971 to May 2021 were collected. The performance of publication covering annual outputs, document types, language of publication, mainstream journals, the impact of the research by research area, coastal habitat type and study area were investigated. Thereafter, co-word, co-authorship, co-country analysis and cluster analysis were conducted using VOSviewer software. The findings underscore a clear disparity in the research evolution. 52% of the total publications were produced between 2011 and 2021. 80% of them were published as journal articles. Journal of Materials and Environmental Science was the most active journal. Behind Morocco, France and Spain researchers have made the main contributions to this research area. 75% of publications have been limited to the coastlines and lagoons. In contrast, habitats such dayas and oasis have received little attention. Hydrobiology and ecology have being gradually deepened. The analysis also revealed a significant research bias against the south–central coastline, the regions of Moroccan Atlantic that have a high research need. This analysis suggests that future scientific effort on Moroccan Atlantic coastal ecosystems should relieve existing biases by increasing multidisciplinary integrated system research and encouraging inter-regional transfer of research resources to areas of low research effort, with a special emphasis on the critical research ecosystems in the southern coastline. Finally, some key recommendations were raised for strengthening the implementation of knowledge management within the concept of sustainable coastal management. [ABSTRACT FROM AUTHOR]

The Benxi Formation in the Ordos Basin is an important gas-producing layer in the Yanchang gas field. There are critical changes in the microfacies type and extension trend of sandbodies, which affects the understanding of reservoir formation and the deployment of development wells. Based on many core and thin section observations, as well as statistical analyzes of sandstone thickness and percentage of sandstone content from 1446 wells, we analyzed the coastal changes and control factors of the microfacies type, planar morphology and distribution of the Benxi Fm sandbodies in the field. The results indicate that the Benxi Fm of the Yanchang gas field is generally composed of terrigenous coastal clastic barrier deposits in a medium to small tidal range environment, but the wave action in the southern region is weak, forming typical barrier sandbars and backbarrier deposits. The wave actions in the north change more strongly, forming three major microfacies sandbodies: reworked barriers, shoals and incised valley filled tidal channels. The barrier sandbodies are arranged in a belt or bead-like pattern parallel to the shoreline and are distributed longshore near the provenance. The oval-shaped shoal sandbodies are dispersed further from the shoreline, and the filling of tidal channel sandbodies is controlled by ancient geomorphic grooves. This research has important guiding significance for the identification and evaluation of reservoirs in the Yanchang gas field and similar geological settings. [ABSTRACT FROM AUTHOR]

A key control on the magnitude of coastal eutrophication is the degree to which currents quickly transport nitrogen derived from human sources away from the coast to the open ocean before eutrophication develops. In the Southern California Bight (SCB), an upwelling-dominated eastern boundary current ecosystem, anthropogenic nitrogen inputs increase algal productivity and cause subsurface acidification and oxygen (O 2 ) loss along the coast. However, the extent of anthropogenic influence on eutrophication beyond the coastal band, and the physical transport mechanisms and biogeochemical processes responsible for these effects are still poorly understood. Here, we use a submesoscale-resolving numerical model to document the detailed biogeochemical mass balance of nitrogen, carbon and oxygen, their physical transport, and effects on offshore habitats. Despite management of terrestrial nutrients that has occurred in the region over the last 20 years, coastal eutrophication continues to persist. The input of anthropogenic nutrients promote an increase in productivity, remineralization and respiration offshore, with recurrent O 2 loss and pH decline in a region located 30–90 km from the mainland. During 2013 to 2017, the spatially averaged 5-year loss rate across the Bight was 1.3 mmol m - 3 O 2 , with some locations losing on average up to 14.2 mmol m - 3 O 2 . The magnitude of loss is greater than model uncertainty assessed from data-model comparisons and from quantification of intrinsic variability. This phenomenon persists for 4 to 6 months of the year over an area of 278,40 km 2 (∼ 30% of SCB area). These recurrent features of acidification and oxygen loss are associated with cross-shore transport of nutrients by eddies and plankton biomass and their accumulation and retention within persistent eddies offshore within the SCB. [ABSTRACT FROM AUTHOR]

Despite increasing risks from sea-level rise (SLR) and storms, US coastal communities continue to attract relatively high-income residents, and coastal property values continue to rise. To understand this seeming paradox and explore policy responses, we develop the Coastal Home Ownership Model (C-HOM) and analyze the long-term evolution of coastal real estate markets. C-HOM incorporates changing physical attributes of the coast, economic values of these attributes, and dynamic risks associated with storms and flooding. Resident owners, renters, and non-resident investors jointly determine coastal property values and the policy choices that influence the physical evolution of the coast. In the coupled system, we find that subsidies for coastal management, such as beach nourishment, tax advantages for high-income property owners, and stable or increasing property values outside the coastal zone all dampen the effects of SLR on coastal property values. The effects, however, are temporary and only delay precipitous declines as total inundation approaches. By removing subsidies, prices would more accurately reflect risks from SLR but also trigger more coastal gentrification, as relatively high-income owners enter the market and self-finance nourishment. Our results suggest a policy tradeoff between slowing demographic transitions in coastal communities and allowing property markets to adjust smoothly to risks from climate change. Subsidies for coastal management and tax advantages for high-income property owners dampen the negative effects of climate risks on coastal property values. Without subsidies or tax advantages market prices better reflect climate risks, but coastal gentrification could accelerate. [ABSTRACT FROM AUTHOR]

The Tahitian (or Polynesian) chestnut Inocarpus fagifer is distributed widely in tropical South-East Asia and in the Pacific region. It is an important component in traditional agroforestry systems. However, its importance as a food plant has decreased considerably. There is no evidence that the species has ever been domesticated, nor that deliberate breeding and crop improvement is presently taking place. This article aims to provide an overview of the current status of knowledge about its distribution, biology, its past and current cultivation and use as a species in agroforestry systems, and to analyse its future potential for production, commercial use and plant improvement. Inocarpus fagifer grows in lowlands in coastal and near coastal areas, often along rivers. It often forms almost pure stands underneath the canopy trees. Inocarpus fagifer trees are very vigorous and shade-tolerant. They thrive in moist to wet soils. Nearly all parts of the tree have been used for multiple purposes including timber, medicine, and animal fodder. The seed has significant traditional importance as human food, and it plays an important role in the diets of rural communities, in particular during the crop harvesting season. Inocarpus fagifer is mostly disease-free. Reports about the commercial use of I. fagifer remain localised and largely anecdotal. The species retains a good potential for commercial development and for a wider commercial use as an alternative food source. No accessible genebank accessions are available. Fundamental questions on its marketability and genetic potential need to be answered. [ABSTRACT FROM AUTHOR]

On the basis of the latest aeromagnetic data of the northern coastal zone of Taizhou, integrated interpretation is performed in this study by combining airborne gravity data, regional geology, and magnetic susceptibility information. According to different zone and block characteristics of the reduced-to-the-pole (RTP) aeromagnetic data, the magnetic field characteristics and related structural division are determined and described in detail. The variation in aeromagnetic field characteristics reflects tectonic movement, magmatic activity, and stratigraphic distribution, which further delineates the structural characteristics of the basement lithofacies, aeromagnetic anomaly characteristics, and distribution regularity of the magmatic rocks and faults. The Bohai coastal zone, located to the west of the Tancheng-Lujiang fault, is characterized by block-like positive aeromagnetic anomalies. The basement is composed of rocks of the Archean Qianxi, Anshan, and Taishan groups, as well as Paleoproterozoic metamorphic rocks. The area to the east of the Tancheng-Lujiang fault is dominated by variable negative aeromagnetic anomalies. The magnetic field is caused by the metamorphic rocks of the Anshan, Jiaodong, Liaohe, and Fenzishan groups, in addition to several intermediate-acid magmatic rocks. The block-like positive aeromagnetic anomaly in the coastal zone of the South Yellow Sea might be related to Archean metamorphic rocks, and the basement rocks are Proterozoic metamorphic. The dramatic changes in the aeromagnetic anomaly belts in the southern Jiangsu-Wunansha region and the Zhejiang-Fujian coast are attributed to the strong reformation of the Proterozoic metamorphic basement rocks of weak magnetism to Mesozoic-Cenozoic magmatic rocks. The coastal zone of the East China Sea is characterized by NNE positive and negative aeromagnetic anomalies, whereas the metamorphic basement is composed of metamorphic rocks of the Proterozoic Chencai Group. The positive aeromagnetic anomaly belt is a reflection of the magmatic rock belt. In summary, this study reveals the characteristics of basement lithofacies in airborne gravity and aeromagnetic fields, which provides an important reference for geological evolution and the division of tectonic units. [ABSTRACT FROM AUTHOR]

Coastal zones with dense populations, low elevations and/or inadequate adaptive capacity are on the frontline of unprecedented impacts from climate change. The Gulf of Guinea (GoG), stretching from Liberia to Gabon, is in particular vulnerable to coastal flooding caused by local and/or climate-induced sea level rise. In this region, interannual to decadal coastal sea level changes remain poorly understood, mainly due to a lack of tide gauge stations. Here we use nearly three decades (1993–2021) of satellite altimetry data to study the link between the Equatorial Atlantic and coastal GoG sea level variability. The rate of mean sea level rise increased from 3.47 to 3.89 ± 0.10 mm/yr from the Equatorial oceanic domain to the GoG coastal area, with an acceleration of 0.094 ± 0.050 mm/yr2. This corresponds to a mean sea level rise of about 8.9 cm over the entire altimetry period, 1993–2021. We focus on the (extreme) warm/cold events that occur in both the GoG during Atlantic Niños, and along the Angola-Namibia coast during Benguela Niños. Both events are driven by remote forcing via equatorial Kelvin waves and local forcing by local winds, freshwater fluxes and currents intensifications. Analysis of altimetry-based sea level, sea surface temperature anomalies, 20 °C isotherm based PIRATA moorings, and the Argo-based steric and thermometric sea level allows us to follow the coastal trapped waves (CTWs) along the GoG, and its link with major events observed along the strong Equatorial Atlantic warmings in 2010, 2012, 2019 and 2021. Both 2019 and 2021 warming have been identified as the warmest event ever reported in this region during the last 40 years. A lag of 1 month is observed between equatorial and West African coastal trapped wave propagation. This observation may help to better anticipate and manage the effects of extreme events on local ecosystems, fisheries, and socio-economic activities along the affected coastlines. In order to enable informed decision-making and guarantee the resilience of coastal communities in the face of climate change, it emphasises the significance of ongoing study in this field. [ABSTRACT FROM AUTHOR]

We present new chronologies that inform the timing and tempo of shell ring and shell mound construction on the South Atlantic Bight. Our project combines recently acquired dates with legacy radiocarbon dates from over 25 rings and mounds to provide a higher-resolution chronology regarding the occupation and formation of this larger landscape of the earliest fishing villages along the East Coast of the United States. We resolve the ordering and timing of occupation of these rings and mounds through Bayesian statistical modeling. These new models historicize and contextualize these shell rings in ways previously impossible. Specifically, our new chronologies of these villages indicate that the earliest villages were established prior to the invention of pottery. The early period of village establishment evidences isolated village rings, whereas later periods seem to have more villages, but these appear to have been relocated to other areas and/or islands over time. Shell mounds are fewer in number, are spread throughout the time period, and may represent special purpose sites compared to shell-rings. Once villages spread, they quickly adopted new technologies (i.e., pottery) and created new institutions and practiced village relocation, which allowed this way of life to persist for more than a thousand years. [ABSTRACT FROM AUTHOR]

Coastal erosion and flooding are projected to increase during the 21st century due to sea-level rise (SLR). To prevent adverse impacts of unmanaged coastal development, national organizations can apply a land protection policy, which consists of acquiring coastal land to avoid further development. Yet, these reserved areas remain exposed to flooding and erosion enhanced by SLR. Here, we quantify the exposure of the coastal land heritage portfolio of the French Conservatoire du littoral (Cdl). We find that 30% (~40%) of the Cdl lands owned (projected to be owned) are located below the contemporary highest tide level. Nearly 10% additional surface exposure is projected by 2100 under the high greenhouse gas emissions scenario (SSP5-8.5) and 2150 for the moderate scenario (SSP2-4.5). The increase in exposure is largest along the West Mediterranean coast of France. We also find that Cdl land exposure increases more rapidly for SLR in the range of 0–1 m than for SLR in the range 2–4 m. Thus, near-future uncertainty on SLR has the largest impact on Cdl land exposure evolution and related land acquisition planning. Concerning erosion, we find that nearly 1% of Cdl land could be lost in 2100 if observed historical trends continue. Adding the SLR effect could lead to more than 3% land loss. Our study confirms previous findings that Cdl needs to consider land losses due to SLR in its land acquisition strategy and start acquiring land farther from the coast. [ABSTRACT FROM AUTHOR]

The timing of the initial peopling of the Americas is unresolved. Because the archaeological record necessitates discussion of human entry from Beringia into southern North America during the last glaciation, addressing this problem routinely involves evaluating environmental parameters then targeting areas suitable for human settlement. Vertebrate remains indicate landscape quality and are a key dataset for assessing coastal migration theories and the viability of coastal routes. Here, radiocarbon dates on vertebrate specimens and archaeological sites are calibrated to document species occurrences and the ages of human settlements across the western expansion and decay of the Cordilleran Ice Sheet (CIS) during the Late Wisconsin Fraser Glaciation in four subregions of the north Pacific coast of North America. The results show archaeological sites occur after glacial maxima and are generally consistent with the age of other securely dated earliest sites in southern North America. They also highlight gaps in the vertebrate chronologies around CIS maxima in each of the subregions that point to species redistributions and extirpations and signal times of low potential for human settlement and subsistence in a key portion of the proposed coastal migration route. This study, therefore, defines new age constraints for human coastal migration theories in the peopling of the Americas debate. [ABSTRACT FROM AUTHOR]

The federally endangered Cape Sable seaside sparrow (Ammospiza maritima mirabilis) is endemic to the Greater Everglades ecosystem in southern Florida, inhabiting fragmented marl prairies in six individual subpopulations. The subspecies is threatened by loss of breeding habitat from fire and water management. Genetic information is severely limited for the subspecies but could help inform decisions regarding subpopulation protections and potential translocations for genetic rescue. To provide genetic data and inform management efforts, feather samples were collected across five subpopulations (designated A–E) and protocols were tested to optimize DNA extraction yields. We assessed four mitochondrial DNA markers (N = 36–69) and 12 nuclear microsatellite loci (N = 55) in 108 sparrows. Mitochondrial DNA sequences revealed low haplotype diversity, with NADH dehydrogenase-2 haplotypes matching to most other extant subspecies and to the Atlantic coast subspecies. Nuclear diversity was low compared to other subspecies, but similar across subpopulations. Samples grouped as one population when analyzed by Principal Component Analysis, Bayesian modelling and genetic distance metrics. Limited genetic emigration was detected from one putative migrant. Relatedness was significantly different for sparrows in the most geographically distant subpopulation (A), likely reflecting high self-recruitment and natal site fidelity (P = 0.003). The low to moderate effective population size (NE = 202.4; NE:NC = 0.06) and generation time estimates indicated that unique genetic variation could be lost quickly during stochastic events. The sample sizes were limited, which reduced the power to comprehensively address recent population size reductions and any subsequent loss of genetic diversity. [ABSTRACT FROM AUTHOR]

Coastal zones have great environmental and economic importance, since anthropogenic activities are very intense, and consequently, their water quality can be affected. Spatial and temporal variations in physicochemical parameters [temperature, pH, electrical conductivity (EC), salinity, dissolved oxygen (DO) and turbidity] in the surface water from the São Lourenço Watershed, a coastal zone in southern Brazil, were investigated. The influence of Patos Lagoon on the watershed in dry periods was confirmed by the increase in salinity and EC of up to 6.43 and 10,810.00 µS cm−1, respectively. In addition, the DO content with low values at the mouth in some samplings, below the Brazilian legislation, calls attention for the water quality. The principal component analysis showed considerable differences in the lower course by comparison with the upper course and the middle course due to climatic and anthropogenic factors. Results from the monitoring enabled to understand fluvial dynamics involving the system of a watershed that contributes to disposal in coastal lagoons through seasonal and climatic factors. Besides, from a managerial point of view, the obtained results support effective decision-making for the preservation of coastal ecosystems. [ABSTRACT FROM AUTHOR]

Coastal ecosystems provide vital services, but human disturbance causes massive losses. Remaining ecosystems are squeezed between rising seas and human infrastructure development. While shoreline retreat is intensively studied, coastal congestion through infrastructure remains unquantified. Here we analyse 235,469 transects worldwide to show that infrastructure occurs at a median distance of 392 meter from sandy shorelines. Moreover, we find that 33% of sandy shores harbour less than 100 m of infrastructure-free space, and that 23–30% of this space may be lost by 2100 due to rising sea levels. Further analyses show that population density and gross domestic product explain 35–39% of observed squeeze variation, emphasizing the intensifying pressure imposed as countries develop and populations grow. Encouragingly, we find that nature reserves relieve squeezing by 4–7 times. Yet, at present only 16% of world's sandy shores have a protected status. We therefore advocate the incorporation of nature protection into spatial planning policies. In a first global analysis, researchers find that sandy shores are severely squeezed between human infrastructure and the rising sea, as on average, the first road or building is currently situated at just 390 meters distance from the shoreline. [ABSTRACT FROM AUTHOR]

Purpose: Mangrove ecosystems which play a critical role in global C sequestration have recently become threatened by global warming and sea level rise. This study aimed to explore the responses of SOC mineralization and C pool stability in mangrove ecosystems to warming and flooding conditions. Methods: Laboratory incubation and solid-state 13C nuclear magnetic resonance (13C-NMR) analysis were used to evaluated soil organic carbon (SOC) mineralization and stability under warming (ST), flooding (SW), warming in coincidence with flooding (SWT), and soil under normal temperature taken from a subtropical mangrove ecosystem in southeastern China. Results: The cumulative SOC mineralization of ST increased by 24%, while SWT and SW decreased by 59% and 68% relative to CK, respectively. Furthermore, the 13C-NMR analysis showed that O-alkyl C was the dominant SOC chemical composition in all treatments (37.1–43.1%), followed by the aromatic C and alkyl C. The aromaticity index (AI) decreased, and the ratio of alkyl and O-alkyl to aromatic (Alip/Arom) increased in all treatments compared with CK, while the alkyl C/O-alkyl C ratio (A/O-A) and hydrophobicity index (HI) were higher for ST and SW but lower for SWT. Warming significantly facilitated SOC mineralization, and lowered SOC stability due to the high cumulative CO2-C production, while flooding had the opposite effects. However, warming in coincidence with flooding led to low SOC decomposition and a more recalcitrant substance. Conclusion: The theoretical elevated CO2 release from mangrove soils under warming in coastal zones might be partially offset by prolonged flooding. The different effects on the chemical fractions, chemical compositions, and stability of the SOC pool in mangrove soil under warming and flooding might further complicate the research on coastal carbon sinks. [ABSTRACT FROM AUTHOR]

Tropical cyclone (TC) rapid intensification (RI) in the nearshore region often poses a serious threat to populated coastal regions. Although several previous studies have revealed an increased probability of RI events just before landfall in North America under global warming, it is unknown whether a similar increase has occurred along China coast. Here, we examine the long-term change of TC RI events along China coast during 1981–2020. Results show that the RI events along China coast have experienced a statistically significant increase since 1981, particularly in the latest decade. Further analysis reveals that the local sea surface temperature, maximum potential intensity, upper-level divergence, low-level vorticity, and vertical wind shear along China coast become increasingly favorable for TC RI occurrence. Among these factors, the intensified maximum potential intensity caused by the significant warming along China coast is the most important factor, most likely contributed by global warming instead of internal climate variability. This result is further confirmed by the CMIP6 model simulations. [ABSTRACT FROM AUTHOR]