A survey of tissue-δ15N and tissue-N values in the green macroalga, Ulva, was conducted around the coast of New Zealand to determine if these indices could be used as indicators of anthropogenic nutrient loading in coastal waters. In addition, data from four case studies showed temporal and spatial responses of tissue-δ15N and tissue-N in Ulva to significant terrestrial nutrient inputs. Tissue-δ15N in Ulva from ‘natural’ exposed coastal sites showed a relatively narrow baseline range of values (6.6±0.1–8.8±0.1‰) in both summer and winter that was consistent throughout New Zealand. Departures in Ulva tissue-δ15N ratios outside this range, particularly when coupled with high (>3.1%) tissue-N values, indicate significant contributions of terrestrially-derived nitrogen to coastal seawater. We note that tissue-N content is also affected by exposure, light and season; however provided such factors are taken into account Ulva can be a cost-effective indicator of relative changes in both source and amount of nitrogen-loading.

As part of a continuing toxic microalgae monitoring program, phytoplankton samples were collected on 16–17 August 2012 at several sampling sites in the southern part of the Bahía de La Paz. A bloom of the dinoflagellate Cochlodinium polykrikoides was detected. Abundance of C. polykrikoides ranged from 73 to 276×103cellsL−1 on the first day to 980–1425×103cellsL−1 on the second day. Study of live specimens showed great variation in cell size and form, mainly as single cells or chains of two cells. Live cells were 30–47μm long and 20–35μm wide (n=30). Seawater temperature during the bloom was 29–30°C. Low densities of Cochlodinium convolutum, Cochlodinium helicoides, and Cochlodinium shuettii were also found in the samples of the bloom event. These high densities of C. polykrikoides did not lead to fish die-offs in the bay.

We compare the chromatographic signatures of petroleum biomarkers in Deepwater Horizon (DH) source oil, three other reference crude oils, DH emulsified mousse that arrived on Alabama’s shoreline in June 2010, and seven tar balls collected from Alabama beaches from 2011 to 2012. Characteristic hopane and sterane fingerprints show that all the tar ball samples originated from DH oil. In addition, the diagnostic ratios of various hopanes indicate an excellent match. Quantitation data for C30αβ-hopane concentration levels show that most of the weathering observed in DH-related tar balls found on Alabama’s beaches is likely the result of natural evaporation and dissolution that occurred during transport across the Gulf of Mexico prior to beach deposition. Based on the physical and biomarker characterization data presented in this study we conclude that virtually all fragile, sticky, brownish tar balls currently found on Alabama shoreline originated from the DH oil spill.

We examine macrofaunal and physico-chemical responses to organic enrichment beneath salmon farms in contrasting flow environments, and reveal pronounced flow-related differences in the magnitude and spatial extent of effects. Total macrofaunal abundances at high flow sites were nearly an order of magnitude greater than at comparable low flow sites, representing a significant benthic biomass. These very high abundances occurred in conjunction with moderate-to-high species richness, and were evident in the absence of appreciable organic matter accumulation. Biological responses to increasing sulfide were variable; however a significant biological threshold was evident at 1500μM. Macrofaunal responses at high flow sites differed substantially from the Pearson–Rosenberg model. The atypical ecological conditions were attributed to (i) limited accumulation of fine sediments, (ii) maintenance of aerobic conditions in near-surface sediments, and (iii) an abundant food supply. Thus, enhanced resilience to organic waste at well-flushed sites appears related to both biological and physical processes.

Surface sediments samples were collected from 9 stations of the Cochin estuary during the monsoon, post-monsoon and pre-monsoon seasons and were analyzed for grain size, total organic carbon (OC), total nitrogen (TN) and stable isotopic ratios of carbon (δ13C) and nitrogen (δ15N) to identify major sources of organic matter in surface sediments. Sediment grain size is found to be the key factor influencing the organic matter accumulation in surface sediments. The δ13C values ranges from −27.5‰ to −21.7‰ in surface sediments with a gradual increase from inner part of the estuary to the seaward side that suggest an increasing contribution of marine autogenous organic matter towards the seaward side. The δ15N value varies between 3.1‰ and 6.7‰ and it exhibits complex spatial and seasonal distributions in the study area. It is found that the dynamic cycling of nitrogen through various biogeochemical and organic matter degradation processes modifies the OC/TN ratios and δ15N to a considerable degree. The fraction of terrestrial organic matter in the total organic matter pool ranges from 13% to 74% in the surface sediments as estimated by δ13C based two end member mixing model.

This study examined the interactive effects of copper and elevated temperature and subsequent depuration on Platygyra acuta coral larvae. Larval mortality and motility were significantly affected by copper alone (70% and 100% inhibition respectively). Their respective lethal/inhibitory concentration (LC50/IC50) were 10–130% and 86–193% higher than those reported for other larvae. Temperature (ambient, 27°C and elevated, 30°C) alone and the combination of temperature and copper did not significantly affect both endpoints. This study provides the first quantitative data on depuration effect on resumption of larval motility after copper exposure, although no sign of larval recovery was observed. These findings suggest that the effects of copper pollution outweigh the thermal tolerance of coral larvae. High LC50 and IC50 recorded may be unique for corals from marginal reefs like Hong Kong which have already been exposed to high levels of copper pollution.

Samples of the polychaete Chaetopterus variopedatus, worm tubes, commensal crab Polyonyx gibbesi and sediments were collected in eight sites in Todos os Santos Bay, Brazil, in order to evaluate the potential use of the polychaetes and crabs as biomonitors and to assess the relationships and accumulation of trace and major elements in different benthic compartments. Trace and major elements were determined by ICP OES. Organic carbon, total nitrogen and sulfur were determined by CNS elemental analyser. Tubes, crabs and polychaetes were important in the retention of trace and major elements. Metals that presented the highest accumulation in polychaetes (i.e. Mg>Al>Fe>Zn>Mn>Co>Cu>Ba>Cr) where the same for crabs (i.e. Mg>Al>Fe>Mn>Co>Zn>Cu>Ba>Cr). High concentrations of Al, Ba, Cr, Mn and Fe, from terrigenous sources, were observed in tubes, which presented accumulation factors up to 81.5 for Mn. Sedentary polychaetes are seen as good biomonitor alternatives for metal contamination studies, because they are one of the most abundant taxon in the benthic system, live in direct contact with sediments, are present in broad distributions and can also handle relatively high concentrations of metals ensuring chronic exposition. The possibility to work with not only the polychaete but also its tube offers advantages compared to bivalves that generally do not accumulate certain metals in very high levels.

The International Convention for the Control and Management of Ship’s Ballast Water and Sediments sets requirements to prevent organism transfers. Vessels on certain routes can be exempted from such requirements based on risk assessment (RA). As the convention nears its entry into force, the interest in exemptions increases. Such RA should be conducted according to the International Maritime Organization G7 Guidelines. We present a RA study for exemptions applied to intra-Baltic shipping considering different RA methods, i.e., environmental matching, species specific method including target species and species biogeographical aspects. As reliable species data in the ports considered are unavailable and following the precautionary principle, no exemptions should be granted. To ensure data reliability, port baseline surveys and regular monitoring programs should be undertaken during the exemption period as new species found influence the RA result. The RA model prepared is considered as of value to other areas worldwide.

Marine water quality monitoring is performed for compliance with regulatory issues, trend detection, model validation and assessment of the effectiveness of adopted policies. As the end users are managers and policy makers, the objectives should be of practical interest and the answers should reduce the uncertainty concerning environmental impact, supporting planning and decision making. Simple and clearcut answers on environmental issues require synthesis of the field information using statistics, simulation models and multiple criteria analysis (MCA). Statistics is easy to apply whereas simulation models enable researchers to forecast future trends as well as test different scenarios. MCA allows the co-estimation of socio-economic variables providing a compromise between scientists’ and policy makers’ priorities. In addition, stakeholders and the public have the right to know and participate. This article reviews marine water quality monitoring principles, design and data analysis procedures. A brief review of international conventions of regional seas is also included.

Surface water samples were collected from substations along Sheva creek and Dharamtar creek mangrove ecosystems of Uran (Raigad), Navi Mumbai, west coast of India. Water samples were collected fortnightly from April 2009 to March 2011 during spring low and high tides and were analyzed for pH, Temperature, Turbidity, Total solids (TS), Total dissolved solids (TDS), Total suspended solids (TSS), Dissolved oxygen (DO), Biochemical oxygen demand (BOD), Carbon dioxide (CO2), Chemical oxygen demand (COD), Salinity, Orthophosphate (O-PO4), Nitrite–nitrogen (NO2–N), Nitrate–nitrogen (NO3–N), and Silicates. Variables like pH, turbidity, TDS, salinity, DO, and BOD show seasonal variations. Higher content of O-PO4, NO3–N, and silicates is recorded due to discharge of domestic wastes and sewage, effluents from industries, oil tanking depots and also from maritime activities of Jawaharlal Nehru Port Trust (JNPT), hectic activities of Container Freight Stations (CFS), and other port wastes. This study reveals that water quality from mangrove ecosystems of Uran is deteriorating due to industrial pollution and that mangrove from Uran is facing the threat due to anthropogenic stress.