This study investigated long-term (1980–2009) yields and variability of total organic carbon (TOC) from four major coastal rivers in Louisiana entering the Northern Gulf of Mexico where a large-area summer hypoxic zone has been occurring since the middle 1980s. Two of these rivers drain agriculture-intensive (>40%) watersheds, while the other two rivers drain forest-pasture dominated (>50%) watersheds. The study found that these rivers discharged a total of 13.0×104t TOC annually, fluctuating from 5.9×104 to 22.8×104t. Seasonally, the rivers showed high TOC yield during the winter and early spring months, corresponding to the seasonal trend of river discharge. While river hydrology controlled TOC yields, land use has played an important role in fluxes, seasonal variations, and characteristics of TOC. The findings fill in a critical information gap of quantity and quality of organic carbon transport from coastal watersheds to one of the world’s largest summer hypoxic zones.

Number of heterotrophic bacteria ability to decompose organic phosphorus compounds and the level of phosphatase activity in the sand of two marine beaches (southern coast of the Baltic Sea) differing in the level of anthropopressure were studied. The study showed that the number of bacteria and level phosphatase activity were higher in the sand of the beach subjected to stronger anthropopressure. In both studied beaches bacteria hydrolysing DNA were the most numerous (92.7–302.8CFU·g−1 d.w.). The least numerous were phytin (26.0·103CFU·g−1 d.w.) and phenolphthalein diphosphate (11.1·103CFU·g−1 d.w.) decomposing bacteria. Number of bacteria able to attack tested organic phosphorus compounds were the most numerous in dry zones (10.77–739.92CFU·g−1 d.w.) then wet zones (3.34–218.15CFU·g−1 d.w.). In both studied beaches bacteria hydrolysing organic phosphorus compounds and phosphatase activity generally were more numerous in surface sand layer. Seasonal variation in the occurrence of bacteria in both studied beaches was observed.

Facing a generalized increase in water degradation, several programmes have been implemented for protecting and enhancing the water quality and associated wildlife, which rely on ecological indicators to assess the degree of deviation from a pristine state. Here, single (species number, Shannon–Wiener H’, Pielou J’) and multi-metric (Estuarine Fish Assessment Index, EFAI) community-based ecological quality measures were evaluated in a temperate estuary over an 8-year period (2005–2012), and established their relationships with an anthropogenic pressure index (API). Single metric indices were highly variable and neither concordant amongst themselves nor with the EFAI. The EFAI was the only index significantly correlated with the API, indicating that higher ecological quality was associated with lower anthropogenic pressure. Pressure scenarios were related with specific fish community composition, as a result of distinct food web complexity and nursery functioning of the estuary. Results were discussed in the scope of the implementation of water protection programmes.

Urban estuaries are susceptible to metal and organic pollution, yet most remain understudied in South Africa with respect to the presence, concentrations and distribution of contaminants. Metal and organic chemical concentrations were assessed in sediment and organisms from different trophic levels in the lower reaches of the Swartkops Estuary. Species sampled included Upogebia africana (Malacostraca: Upogebiidae), Gilchristella aestuaria (Clupeidae), Psammogobius knysnaensis (Gobiidae), Mugil cephalus (Mugilidae), Lichia amia (Carangidae), Argyrosomus japonicus (Sciaenidae), Pomadasys commersonnii (Haemulidae) and Larus dominicanus (Avis: Laridae). This study is one of the most comprehensive studies to date assessing pollution levels in a food web in estuaries in South Africa. Due to biomagnification, higher concentrations of Arsenic, Lead, Mercury and Cadmium were found in the juveniles stages of popular angling fishes. High concentrations of Cadmium and Arsenic were recorded in the liver of L. amia, A. japonicus and P. commersonnii which exceed international quality food guidelines. Eggs from the gull, L. dominicanus, showed detectable concentrations of PCBs.

An assessment of hazard stemming from operational oil ship discharges in the Southern Adriatic and Northern Ionian (SANI) Seas is presented. The methodology integrates ship traffic data, the fate and transport oil spill model MEDSLIK-II, coupled with the Mediterranean Forecasting System (MFS) ocean currents, sea surface temperature analyses and ECMWF surface winds. Monthly and climatological hazard maps were calculated for February 2009 through April 2013. Monthly hazard distributions of oil show that the zones of highest sea surface hazard are located in the southwestern Adriatic Sea and eastern Ionian Sea. Distinctive “hot spots” appear in front of the Taranto Port and the sea area between Corfu Island and the Greek coastlines. Beached oil hazard maps indicate the highest values in the Taranto Port area, on the eastern Greek coastline, as well as in the Bari Port area and near Brindisi Port area.

Pacific angel sharks (Squatina californica) are a benthic elasmobranch that occupy intermediate trophic level positions in coastal food webs. Angel sharks’ life history characteristics make them susceptible to accumulating high amounts of contaminants. Four angel sharks were opportunistically captured in southern California and their liver and uterine contents were analyzed for PCBs, DDTs and other pesticides. High DDT:PCB ratios were found in the sharks indicating direct or indirect foraging near a local EPA Superfund Site. Organic contaminants were measured in ovulated eggs, indicating that females are able to maternally offload contaminants. Despite the potential mismatch between ovarian and uterine fecundity, we estimated females to offload approximately 13±5% of their total body load, which represents the upper limit of this capability. Although low in sample size, the initial findings from this study suggest that habitat use might play an important role in contaminant accumulation in this species.

Seagrass ecosystems represent a global marine resource that is declining across its range. To halt degradation and promote recovery over large scales, management requires a radical change in emphasis and application that seeks to enhance seagrass ecosystem resilience. In this review we examine how the resilience of seagrass ecosystems is becoming compromised by a range of local to global stressors, resulting in ecological regime shifts that undermine the long-term viability of these productive ecosystems. To examine regime shifts and the management actions that can influence this phenomenon we present a conceptual model of resilience in seagrass ecosystems. The model is founded on a series of features and modifiers that act as interacting influences upon seagrass ecosystem resilience. Improved understanding and appreciation of the factors and modifiers that govern resilience in seagrass ecosystems can be utilised to support much needed evidence based management of a vital natural resource.

Heavy metal concentrations and physicochemical parameters in seawater were measured in Guangdong coastal waters, South China. Results showed that the concentrations and distribution of heavy metals varied spatially and seasonally. Generally, heavy metal concentrations in the east regions were higher than in the west. Concentrations of Pb, Zn, Cd and Cr in wet seasons were generally higher than in dry seasons owing to the seasonal differences of the river discharge, rainfall and seawater intrusion. Principal component (PC) analysis showed that PC1, PC2 and PC3 in the east were correlated to Pb+Cr+Zn+Cd, As+Cd and Cu, respectively, and they were correlated to Pb+Cr, Zn+Cu+Cd and As+Cu, respectively, in the west. That was maybe due to the differences of local heavy metal sources. The anthropogenic activities contributed more to the main sources of heavy metals, and contamination factors indicated that Zn and Pb pollution was serious in study area.

Particulate matter samples (PM10 and PM2.5) in downtown Nelson, New Zealand were collected from 2006 to 2012. These samples were used to investigate sources of PM10 and PM2.5, and to evaluate long-term trends in PM10 and BC concentrations. Five PM10 and PM2.5 sources were identified using positive matrix factorization: biomass combustion, motor vehicles, secondary sulfate, marine aerosol and soil. Overall, biomass combustion was the dominant contributor to PM10 (48%) and PM2.5 (77%) mass. The biomass combustion factor profile featured arsenic, suggesting that locals were burning copper chrome arsenate-treated timber, an activity that appears to occur throughout New Zealand.Trend analyses on PM10 and black carbon concentrations revealed that both were decreasing year-on-year, at an average rate of 0.5 μg m−3 per year and 100 ng m−3 per year, respectively. This study provides important information for Nelson City Council, who are responsible for managing air quality in Nelson, to effectively manage air quality. This study also shows that relatively simple mitigation measures can instigate decreases in PM and BC concentrations.

The indoor environment of schools where children stay for long periods of time is a matter of primary concern due to the vulnerability and sensibility of children to air pollutant exposure. The aims of this study were to characterize the indoor air quality of elementary schools in Seoul, Korea, to compare the indoor levels according to the surrounding environments and year of remodeling. The air pollutants, including particle matter (PM10), nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxide (CO2), total bacteria count (TBC), total volatile organic compounds (TVOC) and formaldehyde (HCHO), were sampled during autumn from classrooms and laboratories at 116 elementary schools employing natural ventilation. The schools were selected based on their surrounding environments: surrounded by buildings (SB), roadways (RW), and mountains (MT). The indoor air quality measured at elementary schools in Seoul, Korea showed generally low levels of pollutants due to low occupancy and adequate ventilation and the indoor levels of PM10 and TBC in schools near roadways were significantly lower than other surrounding environments due to dispersion of pollutants, without obstruction by buildings and mountains. TVOC and HCHO concentrations of schools remodeled within a year were significantly higher. Therefore, suitable management for school building characteristics is needed.