Humpback whales, Megaptera novaeangliae, breeding off la Reunion Island (Indian Ocean) undergo large-scale seasonal migrations between summer feeding grounds near Antarctica and their reproductive winter grounds in the Indian Ocean. The main scope of the current study was to investigate chemical exposure of humpback whales breeding in the Indian Ocean by providing the first published data on this breeding stock concerning persistent organic pollutants (POPs), namely polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), DDT and its metabolites (DDTs), chlordane compounds (CHLs), polybrominated diphenyl ethers (PBDEs), and methoxylated PBDEs (MeO-PBDEs). Analyses of stable isotopes δ13C and δ15N in skin resulted in further insight in their feeding ecology, which was in agreement with a diet focused mainly on low trophic level prey species, such as krill from Antarctica. POPs were measured in all humpback whales in the order of HCB > DDTs > CHLs > HCHs > PCBs > PBDEs > MeO-BDEs. HCB (median: 24 ng g−1 lw) and DDTs (median: 7.7 ng g−1 lw) were the predominant compounds in all whale biopsies. Among DDT compounds, p,p′-DDE was the major organohalogenated pollutant, reflecting its long-term accumulation in humpback whales. Significantly lower concentrations of HCB and DDTs were found in females than in males (p < 0.001). Other compounds were similar between the two genders (p > 0.05). Differences in the HCB and DDTs suggested gender-specific transfer of some compounds to the offspring. POP concentrations were lower than previously reported results for humpback whales sampled near the Antarctic Peninsula, suggesting potential influence of their nutritional status and may indicate different exposures of the whales according to their feeding zones. Further investigations are required to assess exposure of southern humpback whales throughout their feeding zones.

Mercury (Hg) concentrations and nitrogen (δ15N) and carbon (δ13C) stable isotopic ratios were measured to assess differences in Hg bioaccumulation in four predatory fish species (Mycteroperca microlepis, Lutjanus campechanus, Caulolatilus microps, and Serioli dumerili) of high commercial and recreational importance in Atlantic waters of the southeastern US. Positive relationships existed between Hg and length, weight, and age, for all species, strongest for M. microlepis and L. campechanus. Intraspecific Hg concentrations also strongly correlated with δ15N for all species, and δ13C for only L. campechanus, and S. dumerili. Comparisons of stable isotopes between species and their impact on mean Hg concentration were inconclusive. This study is the first to report Hg concentrations for C. microps. The current study provides data for an under-sampled region, explores how feeding ecology impacts Hg uptake in commonly co-occurring fishes, and raises questions of the importance of sex and reproduction in Hg accumulation for marine fishes.

Studies of shelter use can provide key insights into the ecology, and structural needs of mobile organisms. Using videos, we examined the usage of tabular corals by large reef fishes, over a 10week period, compared to multiple environmental drivers: visibility, tide (and depth), irradiance, wind speed (as a proxy for wave energy) and water temperature. We found that two of these predictor variables (visibility and wind speed) had a significant effect and together accounted for almost half of the variation in tabular coral usage by fishes. Increases in both variables correlated with increased shelter use. To date use of shelters by fishes has primarily been attributed to UV avoidance. Our results support this notion as more turbid conditions (reduced visibility) have an attenuating effect on UV irradiance. Additionally, tabular corals may reduce the energetic costs of increased wave energy by reducing incidental water velocity beneath the structure.

Migration and dispersal can expose wildlife to threats in different parts of their range, particularly for localized anthropogenic threats. Wildlife exposure to metal contaminants may correlate with local anthropogenic emissions. Feather mercury concentrations of adult and juvenile Lesser Frigatebirds (Fregata ariel) and Great Frigatebirds (F. minor) were determined for individuals breeding in the eastern Indian Ocean. Low mercury concentration in juveniles relative to adults, higher mercury concentration in adult females than adult males, and a trend for Lesser Frigatebirds to have higher mercury concentration than Great Frigatebirds implicate non-breeding ground exposure as the major influence on mercury burden. Aspects of foraging ecology are congruent with high exposure occurring in inshore waters of the non-breeding range, particularly in the South China Sea. These findings highlight the need for tighter mercury emission regulations in southeast Asia to minimise the potential threat to frigatebirds and other species dependent on marine resources including humans.

Marine debris (litter) is a complex problem that affects human activities and the marine environment worldwide. The Clean Coast Program in Israel has had some success in keeping most of the coasts clean most of the time, but without understanding the mechanisms of accumulation of marine debris on the coasts of Israel. In 2012, we initiated a study to characterize the types of marine debris, its origins and spatial distribution. Nineteen surveys were done from June 2012 to March 2015 on eight beaches that spanned the coast of Israel. Average debris density was 12.1 items per 100m2 and 90% of the items were plastic. The top debris categories were food wrappers and disposables, plastic bags and cigarette butts. However, there was variation in the top debris categories among the beaches indicating that a flexible approach with multiple options will be important when addressing the marine debris problem.

In this study, we investigated the environmental impacts of scallop culture on two coastal estuaries adjacent the Bohai Sea including developing a quantitative PCR assay to assess the abundance of the bacterial pathogens Escherichia coli and Vibrio parahaemolyticus. Scallop culture resulted in a significant reduction of nitrogen, Chlorophyll a, and phosphorous levels in seawater during summer. The abundance of bacteria including V. parahaemolyticus varied significantly across estuaries and breeding seasons and was influenced by nitrate as well as nutrient ratios (Si/DIN, N/P). Bacterioplankton diversity varied across the two estuaries and seasons, and was dominated by Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes. Overall, this study suggests a significant influence of scallop culture on the ecology of adjacent estuaries and offers a sensitive tool for monitoring scallop contamination.

A geographically extensive investigation was carried out to analyze the concentrations of heavy metals, PCBs and OCPs in the sediments and marine organisms collected from the Liaohe Estuary. In order to determine the spatial distribution and potential ecological risk of heavy metals, the surface sediments were collected from 44 sites in the Liaohe Estuary. The results showed that the heavy metal contents in the sediments were observed in the following order: Cr (11.2–84.8mg/kg)>Cu (1.7–47.9mg/kg)>Pb (4.3–28.3mg/kg)>As (1.61–12.77mg/kg)>Cd (0.06–0.47mg/kg)>Hg (0.005–0.113mg/kg). In comparison with the concentrations of heavy metals and POPs in other regions, the concentrations of As, Pb and DDTs in the Liaohe Estuary were generally low, and other pollutant concentrations were inconsistent with those reported in other regions. The contamination factor (CF), the pollution load index (PLI), the geoaccumulation index and the potential ecological risk index were used to analyze the pollution situation, which showed that the heavy metal pollution in Liaohe Estuary is mainly dominated by Cd and Hg. The concentrations of the four heavy metals varied significantly in the three kinds of tested organisms (fish, mollusk and crustacean), indicating the different accumulative abilities of the species. The results obtained in this study provide useful information background information for further ecology investigation and management in this region.

In recent years, the ecology, security, and sustainable development of modern mines have become the theme of coal mine development worldwide. However, spontaneous combustion of coal under conditions of oxygen supply and automatic exothermic heating during coal mining lead to coalfield fires. Coal spontaneous combustion (CSC) causes huge economic losses and casualties, with the toxic and harmful gases produced during coal combustion not only polluting the working environment, but also causing great damage to the ecological environment. China is the world’s largest coal producer and consumer; however, coal production in Chinese mines is seriously threatened by the CSC risk. Because deep underground mining methods are commonly adopted in Chinese coal mines, coupling disasters are frequent in these mines with the coalfield fires becoming increasingly serious. Therefore, in this study, we analyzed the development mechanism of CSC. The CSC risk assessment was performed from the aspects of prediction, detection, and determination of the “dangerous area” in a coal mine (i.e., the area most susceptible to fire hazards). A new geophysical method for CSC determination is proposed and analyzed. Furthermore, the main methods for CSC fire prevention and control and their advantages and disadvantages are analyzed. To eventually construct CSC prevention and control integration system, future developmental direction of CSC was given from five aspects. Our results can present a reference for the development of CSC fire prevention and control technology and promote the protection of ecological environment in China.

Alpine lakes of the Tatra Mountains were severely affected by acidification, with minimum recorded values of pH ∼4.5 in the mid-1980s. Since the 1990s, a dramatic decrease in the deposition of acidifying compounds has led to a considerable reversal in lake water chemistry (to pH∼5 in the most severely affected lakes). We studied changes of planktonic crustaceans and chironomid occurrence during the acidification period and the following period of recovery from acidification in three categories of 50 Tatra Mountain lakes (non-acidified, acidified and strongly acidified, according to their status at the beginning of the 1980s). In acidified and strongly acidified lakes, the planktonic crustaceans completely disappeared already by about 1976 except for a few individuals of ubiquitous species in littoral zone due to acidification-induced oligotrophication. In strongly acidified lakes, the original planktonic crustaceans disappeared and littoral species became more abundant already before 1976 due to acidification-induced eutrophication and aluminium toxicity. These processes were quickly reversed following the increase in lake water pH. Extinct species started to return to several acidified and strongly acidified lakes already in the beginning of 1990s. The process of recovery was delayed in many other lakes of the same categories, however, or it did not even start before 2008 despite the improved water chemistry and feeding resources (concentration of chlorophyll-a). Compared to planktonic crustaceans, the reaction of chironomids to acidification and recent recovery has been less pronounced. An analysis of sediment records showed that fluctuations in relative abundance of the dominant chironomid taxa and a decrease of their density occurred. In spite of the fact that chironomid fauna exhibited clear signs of recovery in the last two decades, the recovered assemblage does not exactly reflect the pre-acidification status in the lake. The occurrence and higher proportion of more thermophilous chironomid species in some alpine lakes of all categories could be correlated with increasing air temperature. The considerable effect of climatic factors may thus prevent the full re-establishment of the original status even when the acidification stress completely ceases. The delayed return of planktonic crustaceans to some recovered lakes could be a consequence of the short water residence time of these lakes. In addition, a shortening of the water residence time in recent decades, probably related to recent climate change, in interaction with the ecology of planktonic crustaceans, may possibly be causing further delays in their return.

The applications of multilayered graphenes (MLGs), nanocomposites “MLG–decontaminant” and polydicarbonfluoride intercalation compounds for the localization and deactivation of toxic spills and gaseous emissions under technogenic accidents are investigated in this paper. The intercalation compounds contain oxidizers as intercalants, and MLGs are formed destructively by thermolysis of polydicarbonfluoride intercalation compounds. The sorptive capacity of MLGs (about 240 ml of liquid phase per 1 g of MLG) is much higher than in well-known expanded graphites (EGs) obtained from graphite oxide or graphite acid salts. Our investigation revealed the possibility of the production of the “MLG–decontaminant” nanocomposites with the neutralizator content >95% due to the extremely low (down to 0.4 g/l) apparent density of MLG and its high specific surface (about 370 m²/g). The use of these nanocomposites for the acid–base or redox neutralization of contaminants does not result in the overheating, sputtering or evaporation of liquid phases, because their neutralization products sorb into MLGs. It prevents the soil mineralization by liquid or solid deactivated spills. We revealed that polydicarbonfluoride intercalation compounds with oxidizers (ClF₃, HNO₃, N₂O₄) can be efficiently used for the deactivation of spills and gaseous emissions of nitrogen-containing base compounds.