Local Marine Sources Research Articles

Modelled and observed plastic pollution on remote Scottish beaches: The importance of local marine sources

Beach-cleans conducted on the west coast of Scotland investigated the distribution of land- and marine-sourced litter and compared these with a particle tracking model representing the presumed principal land-based source. Modelled particles dispersed widely, even reaching the remote northwest coast, with ‘hotspots’ and ‘coldspots’ on windward and leeward coasts respectively. In beach sampling, however, land-sourced litter represented only 19% of items by count and 8% by weight, while marine-sourced litter represented 46% by count and 62% by weight. The source of the remainder could not be identified. Windward coasts had an average count of 1859 litter items per 100 m, and weight of 14,862 g per 100 m. Leeward coasts had an average count of 32 litter items per 100 m and weight of 738 g per 100 m. Field observations and model predictions were consistent in many respects for land-sourced litter, however marine-sourced litter is dominant on many coastlines.

Pharmaceutical Applications of Chitosan Extracted from Local Marine Sources

Identification of chitosan from new local marine sources could be a great challenge for research in terms of using this biopolymer in various pharmaceutical, environmental or food applications. In the present study, two chitosan powder samples extracted from processed shrimps waste and Rapana venosa eggs capsules were compared with a food supplement sample based on chitosan, from the point of view of spectral analyses (FTIR spectroscopy), of their solubility in dilute acetic acid solutions (1 %), insoluble substances content, and fats binding capacity. In order to determine the fat binding capacity of the tested chitosan samples, different types of cold pressed vegetables oils (olive oil, sunflower oil, soybean oil, argan oil and coconut oil) and animal fats (butter and pork lard) were used. The present study highlighted that the chitosan samples, chemically extracted with low financial efforts by waste recovery of crustaceans and mollusks from Romanian Black Sea coast, could be an important source with high potential. The obtained results showed a good fat binding capacity, especially for chitosan samples extracted from shrimps waste compared to the chitosan sample chosen as reference. These compounds may be successfully used in pharmaceutical applications, in various formulations as dietary supplement, or as useful therapeutic component in the hypocholesterolemia treatment or in prevention of cardiovascular risk, due to their good solubility in dilute acidic solutions and lower values of insoluble content.

Dimethyl sulfide in the summertime Arctic atmosphere: measurements and source sensitivity simulations

Abstract. Dimethyl sulfide (DMS) plays a major role in the global sulfur cycle. In addition, its atmospheric oxidation products contribute to the formation and growth of atmospheric aerosol particles, thereby influencing cloud condensation nuclei (CCN) populations and thus cloud formation. The pristine summertime Arctic atmosphere is strongly influenced by DMS. However, atmospheric DMS mixing ratios have only rarely been measured in the summertime Arctic. During July–August, 2014, we conducted the first high time resolution (10 Hz) DMS mixing ratio measurements for the eastern Canadian Archipelago and Baffin Bay as one component of the Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments (NETCARE). DMS mixing ratios ranged from below the detection limit of 4 to 1155 pptv (median 186 pptv) during the 21-day shipboard campaign. A transfer velocity parameterization from the literature coupled with coincident atmospheric and seawater DMS measurements yielded air–sea DMS flux estimates ranging from 0.02 to 12 µmol m−2 d−1. Air-mass trajectory analysis using FLEXPART-WRF and sensitivity simulations with the GEOS-Chem chemical transport model indicated that local sources (Lancaster Sound and Baffin Bay) were the dominant contributors to the DMS measured along the 21-day ship track, with episodic transport from the Hudson Bay System. After adjusting GEOS-Chem oceanic DMS values in the region to match measurements, GEOS-Chem reproduced the major features of the measured time series but was biased low overall (2–1006 pptv, median 72 pptv), although within the range of uncertainty of the seawater DMS source. However, during some 1–2 day periods the model underpredicted the measurements by more than an order of magnitude. Sensitivity tests indicated that non-marine sources (lakes, biomass burning, melt ponds, and coastal tundra) could make additional episodic contributions to atmospheric DMS in the study region, although local marine sources of DMS dominated. Our results highlight the need for both atmospheric and seawater DMS data sets with greater spatial and temporal resolution, combined with further investigation of non-marine DMS sources for the Arctic.

Levoglucosan and phenols in Antarctic marine, coastal and plateau aerosols

Due to its isolated location, Antarctica is a natural laboratory for studying atmospheric aerosols and pollution in remote areas. Here, we determined levoglucosan and phenolic compounds (PCs) at diverse Antarctic sites: on the plateau, a coastal station and during an oceanographic cruise. Levoglucosan and PCs reached the Antarctic plateau where they were observed in accumulation mode aerosols (with median levoglucosan concentrations of 6.4pgm−3 and 4.1pgm−3, and median PC concentrations of 15.0pgm−3 and 7.3pgm−3). Aged aerosols arrived at the coastal site through katabatic circulation with the majority of the levoglucosan mass distributed on larger particulates (24.8pgm−3), while PCs were present in fine particles (34.0pgm−3). The low levoglucosan/PC ratios in Antarctic aerosols suggest that biomass burning aerosols only had regional, rather than local, sources. General acid/aldehyde ratios were lower at the coastal site than on the plateau. Levoglucosan and PCs determined during the oceanographic cruise were 37.6pgm−3 and 58.5pgm−3 respectively. Unlike levoglucosan, which can only be produced by biomass burning, PCs have both biomass burning and other sources. Our comparisons of these two types of compounds across a range of Antarctic marine, coastal, and plateau sites demonstrate that local marine sources dominate Antarctic PC concentrations.

Amino acids in Arctic aerosols

Abstract. Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids and quantify compounds at fmol m−3 levels. Mean total FAA concentration was 1070 fmol m−3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45–60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m−3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (< 0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanic emissions.

Ports in a Storm

In many parts of the world, shipping-related emissions have already exceeded or are expected to soon exceed those from land-based sources. Shipping emissions can be reduced substantially by using some of the same technologies being applied to land-based sources, including cleaner engines and fuels, exhaust control methods, and operational modifications. Various ports are testing the feasibility of these mechanisms with varying degrees of success. What is perhaps most greatly needed is expedited creation of better regulations at all levels, from the International Maritime Organization to port city authorities.

TESTING ISOSOURCE: STABLE ISOTOPE ANALYSIS OF A TROPICAL FISHERY WITH DIVERSE ORGANIC MATTER SOURCES

We sampled consumers and organic matter sources (mangrove litter, freshwater swamp-forest litter, seagrasses, seagrass epiphytes, and marine particulate organic matter [MPOM]) from four estuaries on Kosrae, Federated States of Micronesia for stable isotope (sigma13C and sigma34S) analysis. Unique mixing solutions cannot be calculated in a dual-isotope, five-endmember scenario, so we tested IsoSource, a recently developed statistical procedure that calculates ranges in source contributions (i.e., minimum and maximum possible). Relatively high minimum contributions indicate significant sources, while low maxima indicate otherwise. Litter from the two forest types was isotopically distinguishable but had low average minimum contributions (0-8% for mangrove litter and 0% for swamp-forest litter among estuaries). Minimum contribution of MPOM was also low, averaging 0-13% among estuaries. Instead, local marine sources dominated contributions to consumers. Minimum contributions of seagrasses averaged 8-47% among estuaries (range 0-88% among species). Minimum contributions of seagrass epiphytes averaged 5-27% among estuaries (range 0-69% among species). IsoSource enabled inclusion of five organic matter sources in our dual-isotope analysis, ranking trophic importance as follows: seagrasses > seagrass epiphytes > MPOM > mangrove forest > freshwater swamp-forest. IsoSource is thus a useful step toward understanding which of multiple organic matter sources support food webs; more detailed work is necessary to identify unique solutions.

Development of a cliff‐top dune indicated by particle size and geochemical characteristics: Rubjerg Knude, Denmark

AbstractParticle size and geochemical data have been used to investigate the development of a large cliff‐top dune at Rubjerg Knude, located on the western coast of Jutland, Denmark. Textural parameters and geochemical ratios provided useful indicators of the dune sediment provenance and mode of evolution of the dune. The dune sediments themselves showed no significant spatial particle size trends and reflect a number of processes, including grainfall, wind‐ripple migration and avalanching (grainflow), which formed a high proportion of the deposits on both the stoss and lee sides of the present dune. Fine grainfall sediments, which have accumulated to form a sandplain in the lee of the dune, show fining and improved sorting with distance, and extend more than 2 km downwind of the dune crest. Comparison of the textural and geochemical data from Rubjerg Knude and other locations on the Jutland coast indicates that, although there is a contribution of sand to the dune from local marine sources, the main source of sand to the cliff‐top dune and sand plain sediments has been provided by the wind erosion of the underlying cliffs, which are composed of Weichselian age sandy glaciofluvial and glaciolacustrine deposits. Optically stimulated luminescence dating indicated an apparent age for the sand at the base of 274 ± 14 years. If this date is reliable, it suggests that accumulation of the aeolian sand in this area began within approximately the last 300 years. Map and photographic evidence indicate that the modern high dune only began to form after 1885, apparently associated with an acceleration in the rate of coastal cliff retreat.

Chemically resolved submicrometric size distribution and external mixing of the Arctic haze aerosols

Atmospheric aerosol particles were collected with filter and impactor samplers at Ny-Alesund, Spitzbergen during an Arctic haze event in the Spring of 1983. Additional integral aerosol parameters particle light scattering coefficient and total number concentration were also measured. The samples were analyzed for mass, elemental and soot content. With the exception of chlorine that was due to local marine sources, concentrations of the chemical species were all highly correlated with each other and with total mass concentration, light scattering and total number concentration. Mass concentration varied between 4 and 12 μg m -3 , other species showed values within the range reported previously under similar conditions. The impactor and total number concentration data were inverted to yield size distributions for the size range 0.01 to 1.0 μm radius. The mode of the total and elemental mass size distributions was in the range 0.13 to 0.26 μm with the exception of soot, which had a mode at slightly less than 0.13 μm. The main mass of the particulate material had hygroscopic properties similar to that previously observed for urban or continental aerosols. However, soot was observed to be associated with particles that were hygrophobic and it was concluded that it was externally mixed. Overall, the aerosol had properties indicative of one that had remained relatively unchanged after transport from its source region. DOI: 10.1111/j.1600-0889.1987.tb00200.x

VIBRIO PARAHÆMOLYTICUS FOOD-POISONING IN BRITAIN

An outbreak of food-poisoning caused by the marine organism Vibrio para- hœmolyticus is described among holidaymakers who had eaten crabs, locally caught, prepared, and dressed. This is the first confirmed outbreak in Britain associated with home-produced sea-food. The serotype concerned was subsequently isolated from other local marine sources. Twelve people are known to have become ill, and it is probable that several times this number were affected but were not ill enough to seek medical treatment.