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The chemical and biological properties of the water column at a Tyrrhenian site (Isola del Giglio) were studied during a 3-year period. The results highlighted the oligotrophic features of the site, characterised by quite low concentrations of organic carbon (on average DOC 102 micromol/L and POC 9 micromol/L). Relevant bacterial biomass (on average 42.1 microg C/L) and a notable activity (in terms of frequency of dividing cells, on average more than 5%) were observed. However, remarkable changes for these parameters were seasonally recorded. The cyclic occurrence, generally during the late spring-summer period, of benthic mucilage indicated that localised distrophic processes may occur. In particular, the benthic mucilage events of 2000 and 2001 were investigated, although some comparative information was available also for 1999 and 2002. The mucilage aggregates generally showed high bacterial colonisation, which have remarkable effects on the organic matter cycle both inside the aggregates and in the surrounding seawater. During the benthic mucilage development, an increase of DOC and POC concentrations was observed (up to 129 and 18 micromol/L, respectively, in June 2000 and up to 145 and 10 micromol/L, respectively, in May and June 2001) in the water column adjacent to the bottom. However, a general decrease of the trophic value of particulate matter (in terms of C/N ratio) was also observed, especially in 2000 after the disappearance of the mucilage. The available energy and organic matter during the mucilage events led to an increased presence of bacteria in the bottom waters of the Isola del Giglio, with maximum biomass values in 2001. Similarly, the replicative activity of bacteria was higher in 2001 (frequency of dividing cells about 5% vs. 3% of 2000). The lower activity of 2000, in addition to the lower trophic value of organic matter and different environmental conditions (namely lower temperature), might be involved in the persistence of mucilage in 2000 with respect to the rapid disappearance observed in 2001.

Abstract The transportation of liquefied natural gas by sea has a strategic function for ensuring the energy security of Poland and, in a broader perspective, also of the countries in the Central and Eastern Europe region (primarily the Visegrad Group - V4 and others). The article points out the importance of Polish LNG/FSRU terminals in diversification and building the region's energy independence. It analyzes the security environment of the Baltic coastal waters, which is the arena for the activity of many countries with different multidimensional interests. A package of threats to maritime critical infrastructure facilities (LNG/FSRU terminals) and cryogenic tankers in the air, surface, and underwater domains is identified, noting the dynamic nature of many of them. The author analyzes the capabilities (strengths and weaknesses) of autonomous maritime systems (USV, UUV-ROV, UAV) in terms of their use to increase the effectiveness of LNG/FSRU terminal security systems. Possibilities of cooperation and achieving a synergy effect within the combined architecture of USV/UUV-ROV/UAV platforms are also indicated. The article presents a package of missions that autonomous systems can perform to increase the safety of operators and reduce the response time to threats, thus increasing the level of protection. The article presents a vision of a modular USV base platform model as a base element for an autonomous system dedicated to protecting LNG terminal/FSRU infrastructure and cryogenic tankers.

While the number of studies investigating the effects of species diversity on ecosystem properties continues to expand, few have explicitly examined how ecosystem functioning depends quantitatively on the degree of niche complementarity among species. We report the results of a microcosm experiment where similarity in habitat use among aquatic snail species was evaluated as a predictor of changes in community and ecosystem properties due to increasing species richness. Replicate microcosms with all possible one- and two-species combinations of a guild of six snail species were stocked with identical initial snail biomass. Microcosms with two species of snails had greater final snail biomass, lower attached algae biomass, and less total organic matter than monocultures. Snail species differed in their use of five distinct habitat types in the microcosms. Similarity in habitat use between a species pair was negatively related to the magnitude of change (e.g., deltaEF [change in ecosystem function]) in dissolved oxygen. periphyton biomass, and accrual of organic matter with a change in diversity. However, using the most stringent criterion for complementarity effects (e.g., Dmax [proportional deviation of the total polyculture yield from the highest yielding monoculture]), a relationship between species' niche similarity and changes in function with increasing species richness was only observed for dissolved oxygen. The identity of snail species present in the microcosms had strong effects on total organic matter, snail biomass, dissolved oxygen, periphyton biomass, and sedimentation rate. In this study, herbivore identity, sampling effects, and niche complementarity all appear to contribute to species richness effects on pond ecosystem properties and community structure. The analytical approach employed here may profitably be used in other systems to quantify the role of niche complementarity in species richness-ecosystem function relationships.

Total petroleum hydrocarbons (TPH), n-alkanes, petroleum-related biomarkers of terpanes and steranes, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the intertidal sediments in the Bay of Fundy, Nova Scotia/New Brunswick, Canada. Sites close to the harbour and more densely populated areas had higher TPH levels than other pristine areas. n-Alkanes presented a typical single bell-shape in n-C16 to n-C35 range and an obvious odd to even carbon preference. Most sites had trace amounts of petroleum biomarkers. Abundant non-alkylated PAHs and lower amounts of alkylated PAHs represented the major input of the incomplete combustion of solid (e.g., coal, coke, biomass, and coal tar) and liquid fuels. The toxicity estimation for PAHs indicates that they did not have potential toxicity to benthic organisms at most sampling sites. However, possible to probable negative effects from the measured PAH concentrations were found for the two samples from Courtenay Bay and Saint Andrews.

The official involvement of Italy in Antarctic research dates back to 1985, when Mario Zucchelli Station (the former Terra Nova Bay Station) was established in Terra Nova Bay. Italy joined the Antarctic Treaty in 1987. This article is an overview of the wide-ranging research in marine biology performed in the last three decades by the author's team in the Ross Sea. Fundamental questions have been addressed, related to cold adaptations--with special attention to the molecular bases--evolved by marine organisms along with progressive cooling in this geographic area, also analysed in comparison with other important areas, such as the Peninsula, the Weddell Sea, the sub-Antarctic and the Arctic. The basic stepping stone of this research was the integration of ecophysiology with molecular aspects, in the general framework of biodiversity, adaptation and evolution. Investigations have addressed a number of Ross Sea taxa, comprising fish, birds, urchins, whales, seals and bacteria. Its significance has special meaning in view of the control that Antarctica exerts on the world climate and ocean circulation, which has awakened great interest in the evolutionary biology of the organisms that live there.

The impact of temporary storage sites for radioactive wastes in Guba Andreeva on the environmental conditions in the coastal zone of the Barents Sea after 50 years of operation is evaluated on the basis of general chronological reconstruction of the dynamics of radioactive contamination of the marine environment. The bottom deposits along the seacoast at different distances from the repository were investigated. It was found that the region of constant impact of the repository on the conditions in the marine environment is localized near the perimeter of the sanitary-protective zone. Growth of the specific activity of 137Cs, 90Sr, 238Pu, 239,240Pu is recorded in sediments layers up to the level 16–20 cm. The impact of the emission of radionuclides from the repository site is not perceptible in the seacoast zone (Motovskii Zaliv). The age of the sedimentary layers was determined: it shows that the significant concentration of 137Cs in the deposits in Motovskii Zaliv corresponds to the mid-1960s and 1986 and is associated with atmospheric fallout of radionuclides as a result of the nuclear weapons tests and the accident at the Chernobyl NPP.

Development of substrate organisms (oysters, barnacles) and the health of a monitored oyster reef were investigated in the Yangtze Estuary. Very low salinity suppressed oyster survival. Nevertheless, middle- to high-salinity significantly increased the abundance and biomass of substrate organisms, and macrobenthos species and diversity. Long-term variation in substrate organisms was steady after a major fluctuation, yet the macrobenthic community structure lagged behind that of oysters. Overall, the oyster reef was in a healthy state. The M-AMBI results showed that its ecological status under high-salinity was better than medium-salinity conditions. Redundancy analysis indicated these results were associated with changes in water salinity and substrate factors. Taken together, our results suggest this constructed intertidal oyster reef has had a positive effect on the community and health status of macrobenthos in the Yangtze Estuary. Further, these ecological benefits increased going from medium- to high-salinity waters, but were generally absent under low salinity.

Abstract Monitoring and Verification (M&V) was reviewed in this journal in 2015 as part of the Special Issue to mark the tenth anniversary of the IPCC report on CCS. This article provides an update, focusing on identifying areas where there has been technical progress. Activity in CCS has continued since 2015, but the shift towards commercial utilization has altered the context for M&V. Published field experimentation, and verification with monitoring methods, has not progressed as much as was hoped. While much high-quality theoretical work has continued, especially in the area of the design of monitoring systems, an imbalance is apparent. One area where field tests have continued, and progress has been marked, is the rapid development of distributed acoustic sensing and its pairing with permanent seismic sources. Progress here has the potential to make seismic monitoring cheaper and less intrusive. Interesting proposals have been made for monitoring with pressure data, but most have not been tested. Methods of monitoring in the marine ecosystem are rapidly being adapted to the requirements of M&V. These methods are well adapted to the quantification of leakage that is mandated in some jurisdictions. Overall, the need for testing the numerous good ideas in field experiments is very apparent.

AbstractClimate change effects along with anthropogenic activities present the main factors that threaten the existence of heritage sites across the north Nile Delta of Egypt close to the coastline of the Mediterranean Sea. Observing the changes in the landscape close to the archaeological sites is an important issue for decision‐makers in terms of reducing the negative impact of natural events and human activities. The coastal heritage sites are becoming strongly threatened by the rising sea level phenomena that will happen due to global warming. Focusing on the distribution of the archaeological sites, this study aims to detect the areas at risk of shoreline erosion or accretion in the northern shoreline of the Nile Delta. In this study, the changes in the northern shoreline of the Nile Delta were observed and calculated during the last hundred years based on the integration between the old topographic maps from surveys in 1900, 1925 and 1945, optical satellite images captured by Landsat in 1972, 1986 and 2000; Sentinel2 2021; and the Radar SRTM data. The results of this study showed that the changes were enormous with a great shoreline erosion process over the last 121 years recorded along the shoreline in the periods between 1900–1925, 1925–1945, 1945–1972, 1972–1986, 1986–2000 and 2000–2021. The areas eroded were about 5.3, 4.7, 5.6, 8.9, 2.5 and 5.4 km2, respectively. Such negative movements caused the loss of two heritage sites, and the expected changes will lead to the loss of additional heritage sites in the next 500 years. Furthermore, a model was suggested for protecting the coastal heritage sites threatened by the risk of submergence. This study can help the decision‐makers to detect the coastal archaeological sites at risk and create innovative solutions for protecting these irreplaceable heritage sites.