Increasing accessibility of coral reefs from the latter third of the 20th century led quickly to recognition of the vulnerability of coral reef communities to a combination of direct and indirect human impacts. Coral reefs are confronted by the stark threats of climate and ocean changes from the increasing number, intensity and forms of human use impacting global and marine systems. Management, particularly of accessible coral reefs, occurs in the context of multiple scale transboundary water column linkages of lifecycle processes and increasing human use of coastal and marine space. Four decades of experience have demonstrated the combined importance of biophysical and socio-economic sciences and sharing knowledge with communities for developing implementing effective management. In the face of environmental and socio-economic change the challenge for science and management is to develop knowledge and management responses that can better understand and increase resilience to improve he outlook for coral reef communities.

Chemical dispersants are well-established as oil spill response tools. Several studies have emphasized their positive effects on oil biodegradation, but recent studies have claimed that dispersants may actually inhibit the oil biodegradation process. In this study, biodegradation of oil dispersions in natural seawater at low temperature (5°C) was compared, using oil without dispersant, and oil premixed with different concentrations of Slickgone NS, a widely used oil spill dispersant in Europe. Saturates (nC10-nC36 alkanes), naphthalenes and 2- to 5-ring polycyclic aromatic hydrocarbons (PAH) were biotransformed at comparable rates in all dispersions, both with and without dispersant. Microbial communities differed primarily between samples with or without oil, and they were not significantly affected by increasing dispersant concentrations. Our data therefore showed that a common oil spill dispersant did not inhibit biodegradation of oil at dispersant concentrations relevant for response operations.

Mercury (Hg) is a highly toxic element for living organisms and is known to bioaccumulate and biomagnify. Here, we analyze the response of benthic foraminifera communities cultured in mesocosm and exposed to different concentrations of Hg. Standard morphological analyses and environmental DNA metabarcoding show evidence that Hg pollution has detrimental effects on benthic foraminifera. The molecular analysis provides a more complete view of foraminiferal communities including the soft-walled single-chambered monothalamiids and small-sized hard-shelled rotaliids and textulariids than the morphological one. Among these taxa that are typically overlooked in morphological studies we found potential bioindicators of Hg pollution. The mesocosm approach proves to be an effective method to study benthic foraminiferal responses to various types and concentrations of pollutants over time. This study further supports foraminiferal metabarcoding as a complementary and/or alternative method to standard biomonitoring program based on the morphological identification of species communities.

This study examined the effects of human lab-generated noise (sweep tone) on the behaviour and biochemistry of a semi-terrestrial crab (Neohelice granulata). The experiment was carried out in tanks equipped with video- and audio-recording systems on a total of seventy-eight specimens. In total, 42 experimental trials with sweep-tone exposure and control conditions were performed using crabs in single and group layouts. After a habituation period of 30 min, the locomotor and acoustic (sound signals emitted by the crabs) behaviours were monitored for 30 min. During this time, the animals in sweep-tone conditions were exposed to ascending sweeps in a bandwidth range of 2.5–25 kHz. Exposure to sweep-tone noise produced significant changes in the number of signals emitted, locomotor behaviours and plasma parameters, such as haemolymph total haemocyte count and glucose, lactate and total protein concentrations, revealing that human noise could represent a disturbance for this crustacean species.

Fibropapillomatosis (FP) poses a significant threat to the conservation of green sea turtles (Chelonia mydas). Polycyclic aromatic hydrocarbons-PAHs are considered mutagenic, carcinogenic and toxic, and can act as cofactor of this disease. In order to evaluate possible differences between green sea turtles with and without FP, we monitored 15 PAHs in liver samples of 44 specimens (24 with FP) captured in Brazil. We detected eight PAHs and quantified phenanthrene in all green sea turtles with FP. Specimens without FP presented lower values than the tumored ones (1.48 ng g−1 and 17.35 ng g−1, respectively; p < 0.0001). There were no significant differences between tumored and non-tumored specimens, among studied areas, or Southwest Atlantic Fibropapillomatosis Score. Even though we found higher concentrations in the liver samples of green sea turtles with FP, further studies are necessary to confirm if these pollutants are involved in the pathogenesis of the disease.

Green algal blooms have occurred in the Yellow Sea for 11 consecutive years since 2007. A “seed bank” comprising micro-propagules including gametes, meiospores, and zygotes, played an important role in the rapid formation of a green tide. In the present study, germination differences among zygotes, meiospores, and gametes were examined. The growth ability and maturation period of alternating generations of sexual Ulva prolifera strains were also assessed. The zygote and meiospore germination rate was 91.67% and 80.29%, respectively, approximately three times greater than that of gametes (30%). In addition, the highest daily growth rate of sporophytes and gametophytes was 266.7% and 288.1%, respectively, and the maturation period of sporophytes and gametophytes was 35.7 and 31.3 days, respectively. These results indicate that sexual reproduction and vegetative growth are mainly responsible for the rapid expansion of macroalgal blooms in the Yellow Sea.

Antarctica and surrounding waters are often considered pristine, but may be subject to local pollution from tourism, fishing and governmental research programme activities. In particular, the quantification of microplastic pollution within the Antarctic Treaty area (south of latitude 60°S) has received little attention. We examined microplastic particle concentrations in sediment samples from 20 locations up to 7 km from Rothera Research Station. The highest concentrations of microplastic (<5 particles 10 ml⁻¹) were recorded in sediment collected near the station sewage treatment plant outfall. The concentrations were similar to levels recorded in shallow and deep sea marine sediments outside Antarctica. The detected microplastics had characteristics similar to those commonly produced by clothes washing. We recommend further research on microplastics around Antarctic stations to inform policy discussions and the development of appropriate management responses.

δ15N values of coastal biota have been used as indicators of land-derived N-loads and sources to estuarine systems and should respond predictably to differences in nitrogen and be sensitive to changes in nitrogen, preferably at the low end of eutrophication. We evaluated Spartina alterniflora as an indicator species of N-loads and sources of δ15N throughout the growing season, and compared the average δ15N to estuarine nitrogen loads and sources for several estuaries receiving different watershed N-loads. δ15N of S. alterniflora differed among estuaries, and these differences were maintained even as δ15N declined during the end of the growing season. δ15N values increased with increasing nitrogen loads to the subestuaries and with increasing percent wastewater-derived nitrogen load. The response of δ15N of S. alterniflora to increased N loads was greater at low N-loads, and decreased as N-loads increased, suggesting that S. alterniflora is a good indicator of incipient nitrogen load.

Silver hake, (Merluccius bilinearis), contributes significant biomass to Northwest Atlantic ecosystems. The incidence of plastic ingestion for 134 individuals collected from Newfoundland, Canada was examined through visual examination of gastrointestinal contents and Raman spectrometry. We found a frequency of occurrence of ingestion of 0%. Through a comprehensive literature review of globally published fish ingestion studies, we found our value to be consistent with 41% (n = 100) of all reported fish ingestion rates. We could not statistically compare silver hake results to other species due to low sample sizes in other studies (less than n = 20) and a lack of standardized sampling methods. We recommend that further studies should 1) continue to report 0% plastic ingestion rates and 2) should describe location and species-specific traits that may contribute to 0% ingestion rates, particularly in locations where fish consumption has cultural and economic significance.

Mangroves have been subject to more metal contamination, including cadmium (Cd). This study evaluated if a relatively short Cd exposure may induce metabolic, morphological and ultrastructural cell disturbance in Avicennia schaueriana. Cd induced evident constraints to seedlings since there was reduction in leaf gas exchanges and the plants did not survive for more than 10 days at a higher Cd exposure in controlled conditions. The highest Cd accumulation was observed in roots and gradually less in stem and leaves. Cadmium induced lignin deposition was observed in xylem cells of all vegetative organs. Intense sclerification in xylem cells, endoderm and change in the hypoderm organization were also detected. Cadmium clearly induced chloroplast deformities with ruptures of its membranes, thylakoids and core and provoked cytoplasm disorganization. These metal constraints under natural conditions for long term can lead to the accumulation of cellular and metabolic damages and jeopardize seedlings establishment and local biodiversity.