Coastal Sites Research Articles

Aqueous VOCs in complex water environment of oil exploitation sites: Spatial distribution, migration flux, and risk assessment

Pollution of the aqueous environment by volatile organic compounds (VOCs) has caused increasing concerns. However, the occurrence and risks of aqueous VOCs in oil exploitation areas remain unclear. Herein, spatial distribution, migration flux, and environmental risks of VOCs in complex surface waters (including River, Estuary, Offshore and Aquaculture areas) were investigated at a typical coastal oil exploitation site. Among these surface waters, River was the most polluted area, and 1,2-Dichloropropane—which emerges from oil extraction activities—was the most prevalent VOC. Positive matrix factorization showed that VOCs pollution sources changed from oil exploitation to offshore disinfection activities along River, Estuary, Offshore and Aquaculture areas. Annual volatilization of VOCs to the atmosphere was predicted to be ∼34.42 tons, and rivers discharge ∼23.70 tons VOCs into the Bohai Sea annually. Ecological risk assessment indicated that Ethylbenzene and Bromochloromethane posed potential ecological risks to the aquatic environment, while olfactory assessment indicated that VOCs in surface waters did not pose an odor exposure risk. This study provides the first assessment of the pollution characteristics of aqueous VOCs in complex aqueous environments of oil exploitation sites, highlighting that oil exploitation activities can have nonnegligible impacts on VOCs pollution profiles.

Backed pieces at Sharbithat SHA-10 (Sultanate of Oman): Technological issues and chronological assessment

Sharbithat 10 (SHA-10) was discovered in 2017 during the first extensive survey of the northern part of the Dhofar region. Located on a vast mesa surrounded by wadi deltaic branches and abundant sources of flint, SHA-10 is characterized by flint scatters, dwellings, and cairns. Initial test trenches revealed a single period stratification sequence, highlighting a rich marine faunal composition and intense flintknapping activity. The fishing equipment, typical of coastal sites from this period, accompanies a distinctive lithic industry comprising blades, backed pieces, and tanged points. Through the study of technological processes leading to the manufacture of these artefacts, analysis of the points’ morphological variability, and examination of the prevalence of backed bladelets, new hypotheses regarding coastal subsistence strategies and chronological issues have emerged. However, the potential co-occurrence of different facies complicates a chronological definition which can be partly clarified by radiocarbon data results. In this communication, we present a preliminary study of this unique assemblage, discuss its chrono-typological implications, and explore their significance within the framework of South Arabian prehistory.

Habitat selection and spatial behaviour of vulnerable juvenile lemon sharks: Implications for conservation

Nearshore environments represent important habitat for many marine vertebrates during their early-life stages. Globally, these coastal sites are impacted by human activities that have the potential to negatively impact biodiversity in ways we do not yet fully appreciate. To improve our understanding of the relevance of mangrove removal in tropical elasmobranch nursery grounds, we studied the globally Vulnerable lemon shark (Negaprion brevirostris) in a mangrove-fringed lagoon in Bimini, The Bahamas, following a decade of coastal development and habitat disruption. We used two years of acoustic telemetry detections and generalised linear mixed models (GLMMs) to evaluate the link between juvenile shark spatial behaviour and six features of their physical environment. AIC-adjusted model-averaged predictions of habitat selection demonstrated that distance from the central mangrove forest was the most important feature for sharks. After updating model averaging to account for overall preference for proximity to the central forest, we found that medium density seagrass was secondarily preferred over all other habitat types (bare sand, sargassum, urban and rocky outcrops, and deep water) within the core use area (probability of use ≥ 50 %). Locally, our results support including this core area in future marine protected area considerations. More broadly, in the face of rapid global population declines of many elasmobranchs and wide-spread habitat fragmentation in coastal marine nurseries, we identified widely applicable habitat features underpinning an area of high ecological significance for a threatened shark during a vulnerable life stage and outlined a habitat selection framework suitable for using marine vertebrate movement data as ecological indicators for future applied conservation.

Probability and severity of climate change threats to natural world heritage sites vary across site specifics and over time

This study contributes a first comparison of current and potential threats to Natural World Heritage Sites from climate change, as assessed by experts, when site and location characteristics (size, year of inscription to the World Heritage list, continent, climate zone and kind of site) are controlled for. The probability of a threat as well as its intensity is analysed. Another novelty lies in the use of data from the IUCN Conservation Outlook Assessment, covering all 245 Natural and Mixed World Heritage Sites across the world for three points in time: 2014, 2017 and 2020. The threat of climate change is broadly defined and includes temperature extremes, rising temperatures, disappearing glaciers, coral bleaching, droughts, desertification, and rising sea levels. Results based on a simultaneous Probit model with random effects show that the probability of actual and potential climate change threats increases over time, but with differences for size, kind of site and location. The probability that a threat is identified is highest for marine and coastal sites, and for those in Latin America, while it is significantly lower for sites on the African continent. Larger sites have a higher probability of being assessed as at risk and the severity of threats is found to be lower for recently inscribed sites. The rate at which the likelihood of a threat assessment increases is consistent for both current and future situations, while the probability of the most severe threat is larger for the current than the future period. A serious threat from climate change is assessed as highest for locations in the tropical monsoon (current period) or the tropical savannah climate (future period). Estimations also show that pure descriptive statistics or bivariate correlations may not correctly identify the risk or the dignity of a threat.

Climate Change Impacts on Maritime Resources in Lebanon Using Satellites Imagery, Chekka Case Study

This paper aims to explore the impact of climate change on underwater and coastal sites over the past few decades, with a specific focus on the Chekka area in North Lebanon. Given its rich maritime archaeology potential, this region has become a focal point, especially with the ongoing developments posing a threat to cultural resources. Detecting climate changes necessitates extensive measurements from various sources globally, including land stations, ships, and satellite imagery. In this study, we concentrate on changes in sea surface temperature (SST) over the last 20 to 40 years. The analysis heavily relies on satellite imagery, with a primary focus on Landsat 8, equipped with two bands of the thermal infrared sensor (TIRS), and Landsat 7, which carries the Enhanced Thematic Mapper Plus (ETM+) sensor, and also Landsat 5 TM. Utilizing QGIS for the calculation of SST, our findings reveal a noteworthy increase of 1° in sea surface temperature over the past two decades. This observation underscores the significance of ongoing climate change and its potential repercussions for the underwater and coastal cultural heritage in the Chekka area and its suburbs.

The combination of detection and simulation for the distribution and sourcing of microplastics in Shing Mun River estuary, Hong Kong

For the first time, combined detection and simulation was performed on microplastic (MP) debris in surface water, sediment, and oyster samples at ten coastal sites of Shing Mun River estuary, Hong Kong at different tidal conditions. The MP debris were extracted and detected using Fourier transform infrared (FT-IR) spectroscopy, and the simulation was conducted using Weather Research & Forecasting Model (WRF) / Regional Ocean Modelling System (ROMS) coupled hydro-dynamic modelling and the subsequent Lagrangian particle tracking.The results demonstrated the majority of polyethylene (with partial chlorine substitution) debris among all the MPs found, and great spatial and tidal variabilities of MP concentrations were observed. The combination of MP observation and simulations referred to the interpretation that a considerable percentage of MPs found in this study originated from South China Sea. Those MPs were probably transported to Tolo Harbour through sea currents and drifted inshore and offshore with tides. This study provided baseline measures of MP concentrations in Shing Mun River estuary and comprehensive understanding for how MPs transport and distribute within a dynamic estuarine system.

Scenic degradation and visual pollution along the Agadir coastline (Morocco): Analysis and management

Visual pollution refers to the degradation of landscape aesthetics, manifesting as visible deterioration. On the Agadir coast in Morocco, factors such as urbanization, erosion, marine wracking, litter, sewage, beach driving, and animal waste contribute to this issue, which detracts from coastal scenery. This study employs the coastal scenery evaluation system (CSES) to conduct a scenic assessment of 40 coastal sites, aiming to describe the current state of visual pollution and inform management interventions. The CSES utilizes a checklist comprising 18 physical and 8 human parameters to calculate a scenic evaluation index (D value), which categorizes coastal sites into five classes. These range from Class I — typically undisturbed natural areas with pristine scenic qualities — to Class V — which are degraded natural areas significantly impacted by human activities. The scenic evaluation classified these sites into three classes. Four sites (10 %) were classified as Class III, fifteen (37.5 %) as Class IV, and twenty-one (52.5 %) as Class V. No sites were classified as Classes I or II. The assessments presented here offer a comprehensive overview of the Agadir coastal scenery and establish a baseline for developing strategies to address visual pollution.

Capturing the fusion of two ancestries and kinship structures in Merovingian Flanders

The Merovingian period (5th to 8th cc AD) was a time of demographic, socioeconomic, cultural, and political realignment in Western Europe. Here, we report the whole-genome shotgun sequence data of 30 human skeletal remains from a coastal Late Merovingian site of Koksijde (675 to 750 AD), alongside 18 remains from two Early to Late Medieval sites in present-day Flanders, Belgium. We find two distinct ancestries, one shared with Early Medieval England and the Netherlands, while the other, minor component, reflecting likely continental Gaulish ancestry. Kinship analyses identified no large pedigrees characteristic to elite burials revealing instead a high modularity of distant relationships among individuals of the main ancestry group. In contrast, individuals with >90% Gaulish ancestry had no kinship links among sampled individuals. Evidence for population structure and major differences in the extent of Gaulish ancestry in the main group, including in a mother-daughter pair, suggests ongoing admixture in the community at the time of their burial. The isotopic and genetic evidence combined supports a model by which the burials, representing an established coastal nonelite community, had incorporated migrants from inland populations. The main group of burials at Koksijde shows an abundance of >5 cM long shared allelic intervals with the High Medieval site nearby, implying long-term continuity and suggesting that similarly to Britain, the Early Medieval ancestry shifts left a significant and long-lasting impact on the genetic makeup of the Flemish population. We find substantial allele frequency differences between the two ancestry groups in pigmentation and diet-associated variants, including those linked with lactase persistence, likely reflecting ancestry change rather than local adaptation.

Climate-induced vulnerability and conservation strategies for coastal heritage sites in the southern Mediterranean Sea using integrated remote sensing and flood modeling

Coastal heritage sites along the southern Mediterranean Sea confront immediate and severe threats from climate change, intensified by rising sea levels and ongoing shoreline erosion. This study presents a comprehensive approach to monitor and safeguard these significant locations, addressing the challenges posed by climate change. Leveraging high-resolution satellite data sources such as Pleiades imagery and Landsat data, shoreline detection was optimized using the Lee Filter and Canny edge detection techniques. Flood modeling and sea-level rise projections were incorporated to comprehensively assess dynamic coastal landscapes. Advanced methods, including the Prophet model, were employed for temperature predictions, showcasing good predictive accuracy. The results provide crucial insights into climate resilience and temperature forecasting amid rising temperatures associated with climate change. Alarming statistics include an annual erosion rate of −4.47 m/year and critical vulnerability to sea-level rise scenarios. In the extreme 4-m sea-level rise scenario, approximately 35 % of the total surface area (approximately 116.79 m2) is projected to be at risk of submersion, emphasizing the severe susceptibility of these sites to climate-induced sea-level rise. Even in the less severe 2-m scenario, around 24 % of the total area (approximately 80.79 m2) could potentially face submersion, posing a substantial threat to the ancient fortifications of the El Borj heritage site. This study underscores the critical role of preserving coastal heritage in addressing the challenges posed by climate change.

Disaster risk management of cultural heritage: A global scale analysis of characteristics, multiple hazards, lessons learned from historical disasters, and issues in current DRR measures in world heritage sites

This study focuses on disaster risk reduction (DRR) in World Heritage (WH) sites around the world. The contents of disaster risk management in management plans, maps, and photographs of target WH sites are examined to understand the characteristics and hazards of heritage sites, lessons learned from historical disasters, and the status and issues in current strategies and measures. Through analyzing these results, it is found that there are diversified hazards in groups of buildings and archaeological sites in Asia and Europe. It is also revealed that fires, earthquakes, strong winds, and floods frequently occurred and caused enormous damage to the heritage sites, as well as human-induced disasters such as terrorism and explosions. Moreover, it was identified that heritage sites with wooden construction or construction partially composed of wooden components were more often damaged by fire, heritage sites located on multiple kinds of terrain were affected by a variety of disasters, and especially coastal heritage sites were exposed to shore erosion and sea level rise related to climate change. Through analyzing the damage, the various fire causes and the need for DRR measures against fires, earthquakes, and floods, become clear, and the urgency to investigate and address human-induced disasters is understood. It is further revealed that few surveyed WH sites have adopted intervention measures for earthquakes, storms, and human-induced hazards.

Mercury cycling in contaminated coastal environments: modeling the benthic-pelagic coupling and microbial resistance in the Venice Lagoon

Anthropogenic activities have been releasing mercury for centuries, and despite global efforts to control emissions, concentrations in environmental media remain high. Coastal sediments can be a long-term repository for mercury, but also a secondary source, and competing processes in marine ecosystems can lead to the conversion of mercury into the toxic and bioaccumulative species methylmercury, which threatens ecosystem and human health. We investigate the fate and transport of three mercury species in a coastal lagoon affected by historical pollution using a novel high-resolution finite element model that integrates mercury biogeochemistry, sediment dynamics and hydrodynamics. The model resolves mercury dynamics in the seawater and the seabed taking into account partitioning, transport driven by water and sediment, and photochemical and microbial transformations. We simulated three years (early 2000s, 2019, and 2020) to assess the spatio-temporal distribution of mercury species concentrations and performed a sensitivity analysis to account for uncertainties. The modeled mercury species concentrations show high temporal and spatial variability, with water concentrations in some areas of the lagoon exceeding those of the open Mediterranean Sea by two orders of magnitude, consistent with available observations from the early 2000s. The results support conclusions about the importance of different processes in shaping the environmental gradients of mercury species. Due to the past accumulation of mercury in the lagoon sediments, inorganic mercury in the water is closely related to the resuspension of contaminated sediments, which is significantly reduced by the presence of benthic vegetation. The gradients of methylmercury depend on the combination of several factors, of which sediment resuspension and mercury methylation are the most relevant. The results add insights into mercury dynamics at coastal sites characterized by a combination of past pollution (i.e. sediment enrichment) and erosive processes, and suggest possible nature-based mitigation strategies such as the preservation of the integrity of benthic vegetation and morphology.

Temporal Variation and Chemical Composition of Wet Atmospheric Deposition From Two Coastal Sites in the Gulf of Mexico

Temporal Variation and Chemical Composition of Wet Atmospheric Deposition From Two Coastal Sites in the Gulf of Mexico

Patterns of prokaryotic activity along the marine planktonic matter continuum

Prokaryotic abundance and activity are commonly assessed by dividing them into two size-fractions: free-living and attached to particles. Nevertheless, organic matter, essential for the growth of heterotrophic prokaryotes, is present in the environment in a continuum of sizes, from purely dissolved to large particles. Therefore, defining the activity of the prokaryotic community would be more accurate by considering all the distinct size fractions. To achieve this, we measured prokaryotic abundance (PA), heterotrophic prokaryotic activity (as leucine incorporation) and extracellular enzyme activities at a coastal site in the NW Mediterranean Sea. We conducted measurements in both bulk seawater and size fractionated samples sequentially passing through 5 different filter types: 0.2–0.8–3–5–10 μm pore size. Our results indicate that the fraction <0.8 μm contained the highest percentage of cells (91.6 ± 1.1 %) and leucine incorporation rates (72.2 ± 3.5 %). Most of the extracellular enzyme activity appeared in the dissolved fraction (<0.2 μm; 19.8–79.4 %), yet the specific activity of the enzymes (per cell activity) was 100–1000 times higher in the particulate (>0.8 μm) than in the free-living (0.2–0.8 μm) fraction. The size fraction with highest specific activities for leucine incorporation and most of the enzyme activities (β-glucosidase, esterase, Leu-aminopeptidase and alkaline phosphatase) was the 5–10 μm fraction. In contrast, the higher specific chitobiase activity in the >10 μm fraction, suggests that the prokaryotic community colonizing large particles might be more specialized in the hydrolysis of organic matter of zooplanktonic origin than the community colonizing smaller particles.

Cliff dynamics in western Crimea

The paper considers the long-term dynamics of clayey cliffs of the Western Crimea in view of the problem of further recreational development of the Crimean Peninsula. Open-source satellite imagery and long-term (over 40 years) cliff section measurements were analyzed. The paper provides data on the geomorphology of individual coastal sites. It is shown that landslides are the main mechanism causing the cliff retreat on the larger part of the coastline. Slumps are typical for the southern part of the region and their movement episodes are relatively rare. Landslides become more active during the winter — spring period, when the moisture content of clayey cliff rocks increases substantially and the abrasion intensifies. Landslides can also be triggered by short-term heavy precipitation, which is usually observed in the summer. There is no definite relationship between the amount of annual precipitation, storm activity and landslide activity, either synchronous or with a time lag. No regularity in landslide dynamics was identified. It was found that the average long-term rates of cliff edge retreat are 0.1–1.2 m/year. In the northern part of the coast, the rates are the highest, decreasing towards the southern part of the region. The obtained average annual rates of cliff edge retreat are significantly less than those previously reported in the literature. There is a decrease in the beach-forming sediment supply due to a reduction in the stretch of the cliffs. Out of 50 km coastline with cliffs, only 39 km are left in the study area due to being covered by various structures and terracing. The paper also discusses anthropogenic activity, which leads to the formation and movement of man-made landslides and an increase in natural landslide activity. It is shown that the construction of transverse beach-retaining structures leads to blocking of littoral sediment transport, and to increase in the cliff retreat rate outside the protected reach.

Short-term trend and temporal variations in atmospheric methane at an Atlantic coastal site in Southwestern Europe

Methane (CH4) was measured at El Arenosillo observatory, in an Atlantic coastal area located in Southwestern Europe, throughout a four-year period (September 2019–December 2023). Short-term trend, temporal variations and patterns were explored. A trend of 12.1 ± 1.1 nmol mol−1 year−1 was obtained based on daily averages. CH4 exhibited its highest mole fraction in cold months and its lowest in summer, and a seasonally varying diurnal cycle was also observed, with peaks in the early morning (7:00–8:00 UTC) and minimum values at 18:00–19:00 UTC. Mitigation strategies should be implemented based on an understanding of CH4 patterns. To achieve this, CH4 variations under an atmosphere governed by two synoptic patterns were studied. The atmospheric dynamic was analysed with the wind fields from ERA5 data reanalysis and the air masses pathways with the back-trajectories computed with the HYSPLIT model. CH4 horizontal distribution was explored with the TROPOMI observations. The CH4 baseline was collected under the influence of Atlantic air, while a rise from 40 to 80 nmol mol−1 was found with continental airflows from the inland Guadalquivir Valley. CH4 under sea-land breezes did not contribute to the increase of CH4. However, XCH4 from TROPOMI showed an accumulation in the marine area of the Gulf of Cadiz. Ongoing CH4 observations will be used to identify potential changes in the trend, understand the contribution of transported CH4 from areas such as the Western Mediterranean Basin, or assess its impact on surface ozone, among other objectives.

Productivity of the eelgrass biotope and the resilience of fisher-hunter-gatherers in prehistoric Denmark

In the shallow coastal waters of the Danish archipelago, eelgrass (Zostera marina) forms extensive and extremely productive stands, which support food webs that are isotopically distinct from those based on the primary productivity of marine phytoplankton. The isotopic signatures of eelgrass and phytoplankton food webs explain much of the variation in δ13C, δ15N and δ34S values in marine vertebrate remains recovered from prehistoric coastal sites in Denmark. Isotope data from human and dog remains reflect the overwhelming importance of the eelgrass biotope to the fisher-hunter-gatherer subsistence during the Late Mesolithic Ertebølle epoch (∼7400-5800 cal BP). By recognising eelgrass and pelagic resources as isotopically distinct, we obtain more accurate diet reconstructions and dietary 14C reservoir effect corrections for Ertebølle individuals. Longstanding research issues, including technology, palaeodemography, and the resilience and sustainability of the Ertebølle economy need to be reassessed in view of the isotopic signature and productivity of the eelgrass biotope in Danish waters. Eelgrass productivity is also pertinent to comparisons between Ertebølle and Neolithic economies in Denmark, and between fisher-hunter-gatherer adaptations in Denmark and neighbouring regions, and may be key to understanding the much-discussed delay in the transition to farming.

Observation-Based Diagnostics of Reactive Nitrogen Recycling through HONO Heterogenous Production: Divergent Implications for Ozone Production and Emission Control.

Understanding of nitrous acid (HONO) production is crucial to photochemical studies, especially in polluted environments like eastern China. In-situ measurements of gaseous and particulate compositions were conducted at a rural coastal site during the 2018 spring Ozone Photochemistry and Export from China Experiment (OPECE). This data set was applied to investigate the recycling of reactive nitrogen through daytime heterogeneous HONO production. Although HONO levels increase during agricultural burning, analysis of the observation data does not indicate more efficient HONO production by agricultural burning aerosols than other anthropogenic aerosols. Box and 1-D modeling analyses reveal the intrinsic relationships between nitrogen dioxide (NO2), particulate nitrate (pNO3), and nitric acid (HNO3), resulting in comparable agreement between observed and simulated HONO concentrations with any one of the three heterogeneous HONO production mechanisms, photosensitized NO2 conversion on aerosols, photolysis of pNO3, and conversion from HNO3. This finding underscores the uncertainties in the mechanistic understanding and quantitative parametrizations of daytime heterogeneous HONO production pathways. Furthermore, the implications for reactive nitrogen recycling, ozone (O3) production, and O3 control strategies vary greatly depending on the HONO production mechanism. On a regional scale, the conversion of HONO from pNO3 can drastically enhance O3 production, while the conversion from NO2 can reduce O3 sensitivity to NOx changes in polluted eastern China.

Characterization of aerosol and its oxidative potential in a coastal semi-rural site of Southern Italy

Considering the scarce number of studies investigating the oxidative potential of PM2.5 in Italy, a measurement campaign was conducted from February 2020 to October 2020 in a coastal semi-rural site of Basilicata (Southern Italy) with the goal to characterize the fine fraction of ambient particulate matter (PM) and investigate its chemical and toxicological properties, by means of oxidative potential. Different instruments such as an automatic low-volume sampler, an aethalometer and an optical particle counter, were employed for the measurement of PM2.5 mass concentration, equivalent black carbon (eBC) concentration and absorption Ångström exponent (AAE), and particle number size distribution in 0.25–31 μm size range, respectively. 108 daily PM samples, collected on quartz fibre filters, were chemically analysed. Organic (OC) and elemental (EC) carbon content was estimated by thermo-optical transmittance technique (TOT), the concentrations of the main water-soluble ions and total elements were determined by ion chromatography and ED-XRF technique, while the oxidative potential of the water-soluble fraction was estimated through the dithiothreitol (DTT) assay. The mean value of PM2.5 mass concentration was 9.2 ± 2.5 μg/m3 and the average contribution of measured species on PM2.5 mass was 3.3% EC; 19.3% OC; 27.0% secondary inorganic aerosol (sum of SO42−, NH4+ and NO3−), and 10.2% of the other ions and elements. The OC and EC contributions to PM2.5 mass and their mean ratio (OC/EC = 6.6 ± 3.1) suggest that the site is affected by the combined contribution of traffic emissions and biomass combustion (domestic heating and agricultural activities), with the latter prevailing over the traffic, as supported by the mean AAE value of 1.3. The mean OP normalized by sampled volume, OPDTTV, was as high as 0.34 ± 0.22 nmol/min·m3, a value comparable to those recorded for PM2.5 in suburban areas of Italy. The correlation between OPDTTV and the chemical species observed in the PM2.5 samples showed a good agreement with the carbonaceous component OC (r = 0.62) and with some ions, K+ and SO42− (r = 0.60). These results identify combustion sources as the most responsible for the relatively high OPDTTV activity of PM2.5 recorded in this area.

Paleodiet reconstructions and human utilization of middle Holocene Equus ferus in northwest Europe

This study uses tooth meso- and microwear together with bone collagen stable isotope ratios (carbon (δ13C), nitrogen (δ15N), and sulphur (δ34S)) to investigate diet and human utilization of two middle Holocene (∼5 ka cal B.P.) populations of wild horses, Equus ferus from northwest Europe. The results of the mesowear analysis places one population (Ginnerup, Denmark) amongst extreme grazers and the other (Hüde I, NW Germany) amongst less-abrasion dominated grazers. These are contrasted by microwear, which suggest that both populations were killed, when browsing. The low microwear scratch variation in the Ginnerup population suggests that the duration of the mortality event(s) was short and confined to the same season. The mesowear analysis further suggests that the horses at Hüde I included more browse in their diet than at Ginnerup. This is supported by depleted δ13C values in the Hüde I population. The δ34S values also differ between the two sites. The higher values at Ginnerup (a coastal site) compared to Hüde I (an inland site) is interpreted as an effect of marine-influenced sulphur-enriched rainfall. Furthermore, the rather consistent δ34S values at the two sites respectively suggest that the horses killed were from locally available herds. In general, δ13C and δ15N isotope values of horses and other animals from Ginnerup and contemporary nearby sites show tendencies towards more depleted values in the horses and other wild herbivores than in livestock. We suggest that this is a result of niche partitioning and hunting pressure. The results presented here further our understanding of some of the youngest known never-domesticated populations of wild horses Equus ferus in northwest Europe.

Quantification of heavy metals in wild gravid female mud crab (Scylla olivacea) collected from different rivers of Sundarbans mangrove region

Heavy metals pollution is one of our major problems in Sundarbans mangrove zone as we all their surrounding rivers. The presence of industrial development in the nearby areas of coastal and marine aquacultures sites are the cause of heavy metals pollution. The aim of the research was to quantify heavy metals in gravid female mud crabs (Scylla olivacea) in three different rivers of Sundarbans region. Mud crabs and their surrounding water and soil sediments were collected from Mongla, Kholpetua, and Kopotakkho rivers. Analysis of river water was conducted in the laboratory of Shiva Analyticals (India) Private Limited, India, whereas live mud crabs and sediment samples were analyzed from Quality Control Laboratory (QCL), Khulna, Bangladesh for the quantification of heavy metals. The results showed that the heavy metals As, Cr, Cd, Hg and Pb were detected in mud crabs and their surrounding river water and sediments, but the concentration of heavy metals in mud crabs was remains below the limit of human’s consumptions except the heavy metal Chromium (Cr). Maximum concentration of heavy metals was detected Kopotakkho river followed by Mongla and Kholpetua river. The concentration of heavy metals was highest in soil sediments followed by mud crabs and river waters. Mud crabs were contaminated by heavy metals that bioaccumulated from their surrounding sediments and water sources. The hierarchy of mean concentrations (mg/kg) of the heavy metals were Pb>As>Cr>Pb>Hg. Heavy metals are carcinogenic for human consumption when exceeded their permissible levels. It is urgent to stop pollution in Sundarbans mangrove zone and led to serve healthy foods for the nations.