Advances in Marine Biology最新文献

The role of abiotic parameters in determining the distribution of coral communities was assessed on the relatively pristine Maputaland reefs of South Africa from comprehensive reef survey data. The reefs, on which 42 communities could be defined, occur within three geographically separate complexes. Patterns in benthic distribution could be partially explained by latitude and depth, in particular, with slope, turbulence and reef aspect playing far less role in that order. A few species were associated exclusively or in high abundance with some of the communities; in most, it was the ratio of otherwise cosmopolitan species within all of the reef complexes that distinguished them. Complex biotic variables were also considered but not quantified and it is likely that low genetic connectivity and high levels of self-seeding result in a measure of isolation of the communities within a latitudinal gradient.

This chapter provides a review of the fate and transport modelling of emerging pollutants (EPs) and discusses the major research challenges. The overwhelming limitation of the past modelling studies has been the lack of data necessary for model validation, thus calling for large-scale field data sampling. The identification and understanding of fate and transport processes and their interactions of the target EPs and the corresponding selection of appropriate parameter values were also challenging. Such limitations and challenges were evidenced by the elaboration of the representative models in the field. The review also reveales that the model parameter values varied significantly with the EPs (and chemical compositions) and media of concerns. Sensitivity analysis was found to be necessary for modelling of those EPs with limited references in the literature. In comparison with traditional water pollutants, the concentrations of many EPs in water bodies are usually low and even at a trace level, leading to uncertainties or inaccuracy in measured data. This could further challenge model calibration and validation, and especially the determination of parameter values when lacking sufficient data support. How to improve the existing models to address such an issue special for EPs is an urgent task for researchers to ensure the accuracy and reliability of modelling results.

Why females would mate with multiple partners and have multiple fathers for clutches or litters is a long-standing enigma. There is a broad dichotomy in hypotheses ranging from polyandry having benefits to simply being an unavoidable consequence of a high incidence of male-female encounters. If females simply give in to mating when it is too costly to avoid being harassed by males (convenience polyandry), then there should be a higher rate of mating as density increases. However, if females actively seek males because they benefit from multiple mating, then mating frequency, and consequently the incidence of multiple paternity of clutches, should be high throughout. To explore these competing explanations, here we review the incidence of multiple paternity for sea turtles nesting around the World. Across 30 rookeries, including all 7 species of sea turtle, the incidence of multiple paternity was only weakly linked to rookery size (r²=0.14). However, using high resolution at-sea GPS tracking we show that the specifics of movement patterns play a key role in driving packing density and hence the likely rate of male-female encounters. When individuals use the same focal areas, packing density could be 100× greater than when assuming individuals move independently. Once the extent of adult movements in the breeding season was considered so that movements and abundance could be combined to produce a measure of density, then across rookeries we found a very tight relationship (r²=0.96) between packing density and the incidence of multiple paternity. These findings suggest that multiple paternity in sea turtles may have no benefit, but is simply a consequence of the incidence of male-female encounters.

Sponges form an important component of benthic ecosystems from shallow littoral to hadal depths. In the deep ocean, beyond the continental shelf, sponges can form high-density fields, constituting important habitats supporting rich benthic communities. Yet these habitats remain relatively unexplored. The oil and gas industry has played an important role in advancing our knowledge of deep-sea environments. Since its inception in the 1960s, offshore oil and gas industry has moved into deeper waters. However, the impacts of these activities on deep-sea sponges and other ecosystems are only starting to become the subject of active research. Throughout the development, operation and closure of an oil or gas field many activities take place, ranging from the seismic exploration of subseafloor geological features to the installation of infrastructure at the seabed to the drilling process itself. These routine activities and accidental releases of hydrocarbons during spills can significantly impact the local marine environment. Each phase of a field development or an accidental oil spill will therefore have different impacts on sponges at community, individual and cellular levels. Legacy issues regarding the future decommissioning of infrastructure and the abandonment of wells are also important environmental management considerations. This chapter reviews our understanding of impacts from hydrocarbon exploration and exploitation activities on deep-sea sponges and the habitats they form. These impacts include those (1) at community level, decreasing the diversity and density of benthic communities associated with deep-sea sponges owing to physical disturbance of the seabed; (2) at individual level, interrupting filtration owing to exposure to increased sedimentation; and (3) at cellular level, decreasing cellular membrane stability owing to exposure to drill muds. However, many potential effects not yet tested in deep-sea sponges but observed in shallow-water sponges or other model organisms should also be taken into account. Furthermore, to the best of our knowledge, no studies have shown impact of oil or dispersed oil on deep-sea sponges. To highlight these significant knowledge gaps, a summary table of potential and known impacts of hydrocarbon extraction and production activities combined with a simple "traffic light" scheme is also provided.

A large amount of polycyclic aromatic hydrocarbons (PAHs) and their heterocyclic analogues (N, S, O) are released to the marine environment from natural oil seeps, oil spills, bilge discharges and input of land-based sources. Many of these compounds are toxic and have a deleterious effect on marine biota. Nitrogen-containing compounds in crude oils are typically present as cyclic compounds such as polycyclic aromatic nitrogen heterocycles (PANHs) and are generally classified into the two categories of nonbasic (N-PANHs) and basic compounds (B-PANHs). Chromatographic analyses of PANHs are easily to be interfered by other oil components without proper sample preparation prior to instrumental analysis. In this work, dual solid phase extraction columns of 3-(isocyanato)propyl-functionalized silica gel (Si-NCO) and silica gel were employed to efficiently separate both N-PANHs and B-PANHs from saturated and aromatic petroleum hydrocarbons, which enable simultaneous accurate analyses of these groups with single sample preparation. Crude oils studied contain various concentrations of N-PANHs including carbazole, benzocarbazole and B-PANHs including quinolone, acridine and benzoacridine as well as their alkylated homologues. These compounds in light fuel and lubricating oil are generally not detected or are only in trace concentration, but have considerable abundance in heavy fuel oils. Crude oils from different sources and various petroleum products have their unique absolute concentrations and relative distribution patterns of PANHs. Chemical fingerprints of PANHs can provide valuable information for forensic oil spill identification and improve the understanding of the fate, behaviour and chemical degradation of spilled crude oil.

Human activity is generating an excess of atmospheric CO₂, resulting in what we know as ocean acidification, which produces changes in marine ecosystems. Until recently, most of the research in this area had been done under small-scale, laboratory conditions, using few variables, few species and few life cycle stages. These limitations raise questions about the reproducibility of the environment and about the importance of indirect effects and synergies in the final results of these experiments. One way to address these experimental problems is by conducting studies in situ, in natural areas where expected future pH conditions already occur, such as CO₂ vent systems. In the present work, we compile and discuss the latest research carried out in these natural laboratories, with the objective to summarize their advantages and disadvantages for research to improve these investigations so they can better help us understand how the oceans of the future will change.

Emerging contaminants (ECs) may pose adverse effects on the marine ecosystem and human health. Based on the analysis of publications filed in recent years, this paper provides a comprehensive overview on three prominent groups of ECs, i.e., brominated flame retardants, microplastics, and biocides. It includes detailed discussions on: (1) the occurrence of ECs in seawater, sediment, and biota; (2) analytical detection and monitoring approaches for these target ECs; and (3) the biological impacts of the ECs on humans and other trophic levels. This review provides a summary of recent advances in the field and remaining knowledge gaps to address, to enable the assessment of risk and support the development of regulations and mitigation technologies for the control of ECs in the marine environment.

This review discusses the occurrence, impact, analysis and treatment of metformin and guanylurea in coastal aquatic environments of Canada, USA and Europe. Metformin, a biguanide in chemical classification, is widely used as one of the most effective first-line oral drugs for type 2 diabetes. It is difficult to be metabolized by the human body and exists in both urine and faeces samples in these regions. Guanylurea is metformin's biotransformation product. Consequently, significant concentrations of metformin and guanylurea have been reported in wastewater treatment plants (WWTPs) and coastal aquatic environments. The maximum concentrations of metformin and guanylurea in surface water samples were as high as 59,000 and 4502ngL^-1, respectively. Metformin can be absorbed in non-target organisms by plants and in Atlantic salmon (Salmo salar). Guanylurea has a confirmed mitotic activity in plant cells. Analysis methods of metformin are currently developed based on high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The removal of metformin from aquatic environments in the target regions is summarized. The review helps to fill a knowledge gap and provides insights for regulatory considerations. The potential options for managing these emerging pollutants are outlined too.

Synthetic musks (SMs) are promising fragrance additives used in personal care products (PCPs). The widespread presence of SMs in environmental media remains a serious risk because of their harmful effects. Recently, the environmental hazards of SMs have been widely reported in various environmental samples including those from coastal and marine regions. This paper provides a systematic review of SMs, including their classification, synthetic routes, analysis and occurrence in environmental samples, fate and toxicity in the environment, as well as the associated risk assessment and pollution control. Research gaps and future opportunities were also identified with the hope of raising interest in this topic.