Anachronistic facies in the Lower Triassic of South China and their implications to the ecosystems during the recovery time

The end-Permian mass extinction not only severely distressed the Paleozoic ecosystems but also dramatically changed the sedimentary systems, resulting in a peculiar Early Triassic ecosystem and submarine environment during the recovery time following the mass extinction. The Lower Triassic is characteristic of the wide occurrence of various distinctive sediments and related sedimentary structures, such as flatpebble conglomerates, vermicular limestone, subtidal wrinkle structures, microbialite, carbonate seafloor fans, thin-bedded limestone and zebra limestone-mudstone. These sediments were common in the Precambrian to Early Ordovician marine settings, and then they occurred only in some extreme and unusual environments with the expansion of metazoan faunas. However, the Early Triassic witnessed an "anachronistic" reappearance of some distinctive sedimentary records in normal shallow marine settings. The study of these anachronistic facies should be of great importance for the understanding of the unique ecosystem and marine environment through the great Paleozoic-Mesozoic transition. The anachronistic facies characterized by vermicular limestone have been documented in many localities in South China and occur at various horizons of the Lower Triassic. Most types of re- ported distinctive sediments over the world have been observed in the Lower Triassic of South China. This provides an excellent opportunity for understanding the Early Triassic environment and its co- evolution with the biotic recovery. Among the anachronistic facies the vermicular limestone is the most characteristic and common distinctive sediments in the Lower Triassic of South China but has received relatively few investigations. Taking it as a case study, we will detail the variation of vermicular limestone and its stratigraphic distribution in the Three Gorges area, Hubei Province. The investigation on the vermicular limestone and other distinctive sediments from the Lower Triassic of South China further indicates that the appearance of anachronistic facies immediately following the mass extinction and the elimination from normal shallow marine facies with the radiation of Mesozoic marine faunas imply the natural response of the sedimentary systems and ecosystems to the great Paleozoic-Mesozoic transitional events and their induced harsh environments. Therefore, the ups and downs of the anachronistic facies may act as a proxy for the evolution of ecosystems independent of fossil analyses.     

Alkylphenols in marine environments: Distribution monitoring strategies and detection considerations

The presence of alkylphenols (APs) in coastal and marine ecosystems is not as well-documented as it is in freshwater ecosystems. This paper reviews reported concentrations of alkylphenol ethoxylates (APEOs) and APs in seawater, sediments and organisms of marine environments such as estuaries, coastal lagoons, bights, harbours or deep sea in order to study their distribution. Overall contamination of marine aquatic compartments by APs and APEOs has been observed, while coastal areas in the vicinity of wastewater discharges are more impacted than deep sea environments, but to a lesser extent than freshwater sites. Sediments act as sinks for APs and APEOs, especially around wastewater discharge sites. Reported AP concentrations in marine organisms are higher in bivalves and gastropods than in fishes. As nonylphenols and octylphenols are estrogenomimetic, biological responses induced in marine organisms are discussed. Finally, we describe the cell bioassay approach for the biodetection of APs.     

Anthropogenic influences on heavy metals across marine habitats in the western coast of Venezuela

Concentrations of ten metals were measured in waters and sediments at 14 sites during four sampling periods (1996–1997). These sites include various marine ecosystems that are highly influenced by industry, tourism and river discharges, nine of which are within the Morrocoy National Park. Spatially, metal concentrations in water were homogenous, whereas in sediments their distributions were related to grain size. Maximum concentrations of cadmium (Cd) and mean concentrations of copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) in water were above the guideline values proposed by NOAA, indicating the potential of these metals for producing chronic effects in marine biota. Sheltered sites showed the highest metal concentrations in sediments; with Cd and Zn above these guidelines. Enrichment factors and geo-accumulation indexes suggested that metals in sediments were largely of natural origin except for Pb, Cd and vanadium (V), which were apparently associated with industrial effluents. A disruption of the spatial distribution of metals after heavy rainfall, when exposed sites reached concentrations as high as those in sheltered sites, showed the influence of nearby rivers. The potential increase of such climatic events could represent additional stress for natural protected areas in the Caribbean.     

Marine environmental impact due to mining activities of El Salvador copper mine,Chile

Marine environmental impact as a result of copper mine tailing dumping in the sea is studied at Chañaral (North of Chile). These dumpings, from the copper mine El Salvador, have hindered harbour activities, caused geomorphological coastal modifications and affected seriously marine coastal ecosystems and recreational activities. At the old dumping site, Chañaral Bay (1938–1974), nearly 150 million tons of fine sediments were accumulated. Tailing discharges at the new dumping site, Caleta Palito, about 8 km north of Chañaral Bay are accumulating approximately at the rate of 25 000 tons of fine sediments per day, plus unknown quantities of chemicals (Cu, As, CN^?). From January 1975 to July 1976, this site has received over 13 million tons of sediments which has caused deterioration of the marine coastal environment, reduction in light penetration and high mortalities among marine invertebrates, fishes and algae.     

Prevalence of microplastics in Singapore's coastal marine environment

Microplastics have been recently identified as marine pollutants of significant concern due to their persistence, ubiquity and potential to act as vectors for the transfer and exposure of persistent organic pollutants to marine organisms. This study documents, for the first time, the presence and abundance of microplastics (>1.6 microm) in Singapore's coastal environment. An optimized sampling protocol for the collection and analysis of microplastics was developed, and beach sediments and seawater (surface microlayer and subsurface layer) samples were collected from nine different locations around the coastline. Low density microplastics were separated from sediments by flotation and polymer types were identified using Fourier transform infrared (FTIR) spectrometry. Synthetic polymer microplastics identified in beach sediments included polyethylene, polypropylene, polystyrene, nylon, polyvinyl alcohol and acrylonitrile butadiene styrene. Microplastics were detected in samples from four out of seven beach environments, with the greatest quantity found in sediments from two popular beaches in the eastern part of Singapore. Polyethylene, polypropylene and polystyrene microplastics were also found in the surface microlayer (50-60 microm) and subsurface layer (1m) of coastal waters. The presence of microplastics in sediments and seawater is likely due to on-going waste disposal practices from industries and recreational activities, and discharge from shipping.     

Design and analysis of the Sydney deepwater ocean outfall environmental monitoring programme: a critique

The Sydney Environmental Monitoring Programme (EMP) measured the environmental performance of Sydney's new deepwater sewage outfalls against a wide range of criteria related to impacts on marine ecosystems and on human use of marine resources. It consisted of a number of interacting studies conducted during the period 1989 to 1993. Given that all the studies have now been finalized and the data analysed and presented (see papers in this volume), it is appropriate to review the program as a whole and identify, with the benefit of hindsight, where things could have been done better. This paper focuses mainly on the experimental design and statistical treatment of the studies conducted, although management problems are also briefly addressed. Overall it is concluded that the studies making up the EMP contributed greatly to enhancing our understanding of the marine environment of the coastal shelf off Sydney, an area which had previously received only limited attention. Most of the studies, however, suffered from deficiencies in experimental design, which was difficult to overcome when analysing the data. It will be important, in designing future integrated monitoring studies, to draw on the experience of programs such as this to avoid some of the pitfalls which appear to be inherent in these types of large programs.     

Trace metal concentrations in sediments from Long Island Sound

It is important to determine trace metal concentrations in marine sediments because these could be important sources of contamination of marine organisms that reside there. In this study we measured the concentrations of thirteen metals in sediments obtained from Long Island Sound. We found great variations in metal levels for various geographic areas in the Sound; but, generally the highest concentrations found were in the extreme western end of the Sound. Comparison is made between metal levels in sediments from the Sound to seven other areas located in the U.S. and U.K.     

Valuation and use of complex ecosystems: An economist's view

This paper surveys approaches to the economic valuation of ecosystems and the determination of their optimal utilisation. The components of the value of ecosystems are defined and methods of measurement are presented. Also discussed is a simple model of the economic use of a dynamic ecological system. Economically optimal trajectories are shown and scenarios are presented in which it is economically optimal to destroy the ecosystem. Particular problems arise if the ecosystem is a common-property resource as is often the case with marine ecosystems. This issue is also addressed. Moreover, the paper presents some extensions of the model that add complexity and uncertainty.     

Organochlorine, Heavy Metal and Polyaromatic Hydrocarbon Pollutant Concentrations in the Great Barrier Reef (Australia) Environment: a Review

Past monitoring of heavy metals, organochlorine compounds and polyaromatic hydrocarbons (PAHs) has found that pollutant concentrations are generally low within the Great Barrier Reef Marine Park and World Heritage Area and are indicative of a relatively unpolluted environment. The exceptions are sites that are adjacent to human activity such as ports and harbours, urban centres and areas adjacent to intensive agricultural activity. These sites have elevated concentrations of a range of pollutants. Concentrations of dioxins have also been found to be elevated in marine park sediments. Elevated pollutant concentrations are generally the consequence of effluent discharge, urban stormwater, and agricultural and industrial runoff. However, a majority of Great Barrier Reef pollutant data are now dated, and contemporary information is required concerning the distribution and impact of pollutants in the Queensland marine environment. The utility of specialized monitoring tools such as biomarkers for tropical marine environments urgently needs to be examined. With this information, appropriate risk assessment and monitoring can be implemented and effective management strategies developed to protect tropical marine ecosystems including the Great Barrier Reef.     

Evaluation of the presence of major anionic surfactants in marine sediments

The contamination of aquatic environments has become the focus of increasing regulation and public concern due to their potential and unknown negative effects on the ecosystems. The present work develops a monitoring and statistical study, based on the analysis of variance test (ANOVA) and the multivariable analysis, both for insoluble soap and LAS in order to compare the behavior of different anionic surfactants in this environmental compartment. First, a novel and successfully validated methodology to analyze insoluble soap in these samples is developed. The matrix effect and the comparison of different extraction techniques were also performed. The optimized analytical methodologies were applied to 48 representative samples collected from the Almeria Coast (Spain) and then a statistical analysis to correlate anionic surfactant concentration and several variables associated with marine sediment samples was also developed. The results obtained showed relevant conclusions related to the environmental behavior of anionic surfactants in marine sediments.     

Characterization of Individual Rock Magnetic Components by Analysis of Remanence Curves, 1. Unmixing Natural Sediments

Natural sediments are a complex mixture of magnetic minerals with different origins and different geochemical history, each of which is called a magnetic component. Magnetic components practically never occur in isolated form, and their characterization using bulk magnetic measurements relies on the individuation of the systematic variation of some parameters within a large group of samples. These variations can be interpreted either as a mixing trend or as the result of natural processes, which affect the physical and chemical properties of the magnetic particles. An alternative approach is offered by the analysis of magnetization curves using model functions, which are supposed to represent the magnetic properties of individual components. The success of this approach relies on (1) the choice of model functions that can reproduce the natural properties of a component with sufficient accuracy by varying a minimum number of parameters and (2) on very precise and accurate measurements, which are necessary to overcome the extreme sensitivity of the method to noise. In this paper, the analysis of remanent magnetization curves proposed by Egli (2003) is applied to a large set of representative sediments from the most variable environments and to a set of artificial magnetite samples. Despite the variety of materials and natural processes involved in the formation of these sediments, seven groups of magnetic components with well-defined and consistent properties could be identified. It has been found that both lacustrine and marine sediments contain two magnetically distinct groups of magnetosomes, which react differently to changes of the redox potential. The effects of some natural processes, such as weathering, reductive dissolution and transport could be observed on the individual components.     

Handling of waste in ports

A present major problem for ports is arranging adequate reception facilities for ship-generated waste, as the lack of such facilities is a problem to many shipowners. To preserve the environment in and around the ports it is necessary also to deal efficiently with the port-generated waste.

Although international conventions on the retention of waste on board ships for subsequent discharge to shore reception facilities have been ratified by most seafaring nations, a considerable part of the ship-generated waste still goes into the sea. Much of the waste generated in ports will also be dumped in quantities that at least affect the local marine environment. The regulations governing the handling of port-generated waste are often national and/or local legislation, whereas the handling of ship-generated waste is governed by the MARPOL Convention in most parts of the world.

The handling of waste consists of two main phases—collection and treatment. Waste has to be collected in every port and on board every ship, whereas generally only some wastes are treated and to a certain degree in ports and on board ships.

This paper considers the different kinds of waste generated in both ports and on board ships, where and how it is generated, how it could be collected and treated. The two sources are treated together to show how some ship-generated waste may be treated in port installations primarily constructed for the treatment of the port-generated waste, making integrated use of the available treatment facilities.

The different types of wastes can be divided into different categories. A world-wide accepted categorization of ship-generated waste has been established in the MARPOL 73/78 Convention. This will also be used for grouping the port-generated waste.     

Water column monitoring near oil installations in the North Sea 2001-2004

Fisheries have been vital to coastal communities around the North Sea for centuries, but this semi-enclosed sea also receives large amounts of waste. It is therefore important to monitor and control inputs of contaminants into the North Sea. Inputs of effluents from offshore oil and gas production platforms (produced water) in the Norwegian sector have been monitored through an integrated chemical and biological effects programme since 2001. The programme has used caged Atlantic cod and blue mussels. PAH tissue residues in blue mussels and PAH bile metabolites in cod have confirmed exposure to effluents, but there was variation between years. Results for a range of biological effects methods reflected exposure gradients and indicated that exposure levels were low and caused minor environmental impact at the deployment locations. There is a need to develop methods that are sufficiently sensitive to components in produced water at levels found in marine ecosystems.     

An oil spill-food chain interaction model for coastal waters

An oil spill-food chain interaction model, composed of a multiphase oil spill model (MOSM) and a food chain model, has been developed to assess the probable impacts of oil spills on several key marine organisms (phytoplankton, zooplankton, small fish, large fish and benthic invertebrates). The MOSM predicts oil slick thickness on the water surface; dissolved, emulsified and particulate oil concentrations in the water column; and dissolved and particulate oil concentrations in bed sediments. This model is used to predict the fate of oil spills and transport with respect to specific organic compounds, while the food chain model addresses the uptake of toxicant by marine organisms. The oil spill-food chain interaction model can be used to assess the environmental impacts of oil spills in marine ecosystems. The model is applied to the recent Evoikos-Orapin Global oil spill that occurred in the Singapore Strait.     

Distribution of faecal coliforms in bottom sediments from the New York Bight

The distribution of faecal coliform densities found in New York Bight sediments indicated that sewage sludge material has contaminated areas extending 11 km north and 37 km south from the disposal site. A high degree of confidence for enumerating faecal coliforms in marine sediments was demonstrated by standard water methodology since 82.3% of the faecal coliform group isolated were Escherichia coli. This study also indicated that marine sediments could be stored 4 days at 4°C without appreciable changes in the faecal coliform count, and that, in situ, faecal coliforms would persist longer when sediment temperatures were low.     

Plastic in the Thames: A river runs through it

Although contamination of the marine ecosystems by plastics is becoming recognised as a serious pollution problem, there are few studies that demonstrate the contribution made by freshwater catchments. Over a three month period from September to December 2012, at seven localities in the upper Thames estuary, 8490 submerged plastic items were intercepted in eel fyke nets anchored to the river bed. Whilst there were significant differences in the numbers of items at these locations, the majority were some type of plastic. Additionally in excess of 20% of the litter items were components of sanitary products. The most contaminated sites were in the vicinity of sewage treatment works. While floating litter is visible, this study also demonstrates that a large unseen volume of submerged plastic is flowing into the marine environment. It is therefore important that this sub-surface component is considered when assessing plastic pollution input into the sea.     

Research on intact marine ecosystems: a lost era

It is proposed that a new, fifth era should be added to the four historical phases of marine research identified by Rupert Riedl, specifically an era devoted to studying and ameliorating disturbed marine ecosystems. In an age of global environmental deterioration, many marine ecosystems and organisms are high on the list of threatened entities. This poor status prompts research that would otherwise have been unnecessary and hinders research that would normally have been conducted. I argue that research into intact marine ecosystems is becoming increasingly difficult, and that most of our future insights into marine habitats will stem from knowledge gained by examining various disfunctions of those systems rather than their functions. The new era will therefore differ from past research in its underlying aim, the range of topics studied, the selection and funding of those topics, the validity of its conclusions, and in its urgency. Sea turtles and cetaceans are cited as case studies at the organismic level, shallow-water benthic communities, including coral reefs, at the ecosystem level.     

Spatial variability of ocean fertilizing nutrients in the dust‐emitting ephemeral river catchments of Namibia

Research into global hot spots of dust emission has focused on exposed fine‐grained sediments in palaeo‐ or ephemeral dryland lake basins including Etosha (Namibia) and Makgadikgadi (Botswana) in southern Africa. Namibia's western ephemeral river valleys are also known to produce dust but have remained largely overlooked as a regionally significant source. Nutrient enrichment of valley sediments and proximity to the South Atlantic suggests aeolian dust could play an important role in ocean fertilization. The fertility of valley dust is dependent on fluvial sediments originating in the upper catchments on the Southern African Central Plateau. In this study we investigate climate, geology, vegetation and land use variability and how these may influence the nitrogen, phosphorus and iron availability in the catchments. We intensely sampled the Huab, Kuiseb and Tsauchab river systems to map the spatial distribution of nutrients from upper catchments to river termini. Samples were analysed for the bioavailable fractions of iron, nitrogen and phosphorus as well as total nitrogen and phosphorus. Results show that the lower valley reaches are sources of aeolian dust enriched in nutrients. Nitrogen levels correlate with precipitation and vegetation levels and phosphorus levels with geology. However, differences in upper catchment sediment nutrient levels were not representative of downstream nutrient differences between valleys. Rather, it is the hydrological and geomorphological processes of the ephemeral river systems that are key for producing the enriched sediments in the lower reaches. We demonstrate that the ephemeral river valleys of western Namibia are an extensive and enriched source of mineral dust that could play a critical role in marine productivity of the southern Atlantic. © 2017 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.     

Assessment of heavy metal impact on sediment quality of the Xiaoqinghe estuary in the coastal Laizhou Bay,Bohai Sea: Inconsistency between two commonly used criteria

Surface sediments in the Xiaoqinghe estuary, southwestern coastal Laizhou Bay, were examined to assess the bio-toxic risk of heavy metals (Cd, Cu, Ni, Pb and Zn) with the effects range-low and effects range-median guidelines (ERL–ERMs) and the concentration ratio of simultaneously extractable metals to acid volatile sulfides ([SEM]/[AVS]). Based on the ERL–ERM guidelines, bio-toxic effect caused by Cu, Ni, Pb and Zn could be expected in the riverine surface sediments of the Xiaoqinghe estuary; and the surface sediments in the marine area were in good quality and only Ni might cause bio-toxic effect occasionally. The AVS–SEM guidelines revealed that no bio-toxic effect could be caused by any of the studied metals in both the riverine and marine sediments, since there were excess sulfides in surface sediments which could form water-insoluble substances with free metal ions and reduce the bioavailability of heavy metals.     

Characterization of Organic Contaminants in New York/New Jersey Harbor Sediments Using FTIR‐ATR and Synchrotron FTIR

Dredging and remediation of contaminated Harbor sediments requires characterization of organic pollutants. In this paper, we apply a combination of Fourier transform IR attenuated total reflectance (FTIR‐ATR) and synchrotron FTIR techniques to the investigation of sediments and related materials from New York/New Jersey Harbor and other locations. The FTIR techniques give information on the functional groups of the compounds found in the sediments and make possible measurements with a spatial resolution of about 0.015 mm. Comparisons of natural organic materials namely, river and groundwater humic substances, recent marine and lacustrine sediments, and ancient sedimentary kerogen show that contaminated NY/NJ Harbor sediments display a strong and distinct absorption in their IR spectra at 2850–2950 cm^?1 identified as a C? H stretching band, indicative of the presence of anthropogenic hydrocarbons. We suggest that the presence of this band could be used for rapid screening for the presence of contaminant organic compounds in sediments encountered in dredging operations and/or as an indicator for the efficacy of sediment decontamination technologies used for treatment of dredged material.