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Correlation between atmospheric deposition of Cd, Hg and Pb and their concentrations in mosses specified for ecological land classes covering Europe
2013
Schröder, Winfried | Pesch, Roland | Hertel, Anne | Schonrock, Simon | Harmens, Harry | Mills, Gina | Ilyin, Ilia
Referring to Europe as a whole and to single European countries, previous studies have shown that heavy metal concentrations in mosses (1) are primarily determined by atmospheric deposition of heavy metals; (2) are country and element–specific; and (3) agree well with respect to element–specific spatial patterns and temporal trends of atmospheric deposition of heavy metals. This paper investigates correlations between the concentrations of cadmium, lead and mercury in atmospheric deposition and mosses within the units of an ecological land classification of Europe. To this end, measurements from the 2005/2006 European moss survey and modeled atmospheric deposition in the previous three years were intersected with a map on ecologically defined land classes of Europe. Then, the minimum numbers of sampling sites required within the ecological land classes were computed. Considering spatial auto–correlations, subsequently the correlations between the concentrations of heavy metals in mosses and corresponding deposition were calculated and mapped for each of those ecological land classes containing moss sampling sites. It was concluded that the numbers of sampling sites within Europe and most participating countries as well as within most of the ecological land classes are sufficient for estimating the mean of measurements for the above mentioned three spatial levels within 20% of its true value with 95% confidence. Spatial patterns of correlations between the atmospheric deposition and bioaccumulation were shown to vary by element and ecologically defined land classes.
Afficher plus [+] Moins [-]Consistent assessment of trace metal contamination in surface sediments and suspended particulate matter: A case study from the Jade Bay in NW Germany
2013
Beck, Melanie | Böning, Philipp | Schückel, Ulrike | Stiehl, Thorsten | Schnetger, Bernhard | Rullkötter, J. | Brumsack, Hans-Jürgen
Recently, within the framework of European directives, the importance of marine monitoring programs has increased. In this study, a dense sampling grid was applied for a detailed assessment of the metal contents of surface sediments and suspended particulate matter from the Jade Bay, one of the tidal basins in the southern North Sea. The local lithogenic background was defined and compared with average shale, a common reference material. Based on the calculated non-lithogenic fraction and a cluster analysis, the metals are distributed in two groups: (i) elements of mainly natural origin (Co, Cr, and a major portion of Cd) and (ii) elements associated with anthropogenic activity (As, Cd, Cu, Ni, Pb, Sn, and Zn). However, even the metals of the second group are enriched by at most a factor of two relative to the local background, suggesting minimal anthropogenic impact. Spatial distribution maps show that the harbor area of Wilhelmshaven may be a particularly important source of metal.
Afficher plus [+] Moins [-]Geo-Chip analysis reveals reduced functional diversity of the bacterial community at a dumping site for dredged Elbe sediment
2013
Störmer, Rebecca | Wichels, Antje | Gerdts, Gunnar
The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring.
Afficher plus [+] Moins [-]One size does not fit all: The emerging frontier in large-scale marine conservation
2013
Toonen, Robert J. | Wilhelm, T ‘Aulani | Maxwell, Sara M. | Wagner, Daniel | Bowen, Brian W. | Sheppard, Charles R.C. | Taei, Sue M. | Teroroko, Tukabu | Moffitt, Russell | Gaymer, Carlos F. | Morgan, Lance E. (Lance Edward) | Lewis, Nai‘a | Sheppard, Anne L.S. | Parks, John | Friedlander, Alan M.
On the 20th anniversary of the Convention on Biological Diversity, a network of very large marine protected areas (the Big Ocean network) has emerged as a key strategy in the move to arrest marine decline and conserve some of the last remaining relatively undisturbed marine areas on the globe. Here we outline the ecological, economic and policy benefits of very large-scale MPAs and show their disproportionate value to global marine conservation targets. In particular we point out that very large-scale MPAs are a critical component of reaching the Aichi targets of protecting 10% of global marine habitats by 2020, because in addition to encompassing entire ecosystems, they will bring forward the expected date of achievement by nearly three decades (2025 as opposed to 2054). While the need for small MPAs remains critical, large MPAs will complement and enhance these conservation efforts. Big Ocean sites currently contain more than 80% of managed area in the sea, and provide our best hope for arresting the global decline in marine biodiversity.
Afficher plus [+] Moins [-]Plastic ingestion in marine-associated bird species from the eastern North Pacific
2013
Avery-Gomm, S. | Provencher, J.F. | Morgan, K.H. | Bertram, D.F.
In addition to monitoring trends in plastic pollution, multi-species surveys are needed to fully understand the pervasiveness of plastic ingestion. We examined the stomach contents of 20 bird species collected from the coastal waters of the eastern North Pacific, a region known to have high levels of plastic pollution. We observed no evidence of plastic ingestion in Rhinoceros Auklet, Marbled Murrelet, Ancient Murrelet or Pigeon Guillemot, and low levels in Common Murre (2.7% incidence rate). Small sample sizes limit our ability to draw conclusions about population level trends for the remaining fifteen species, though evidence of plastic ingestion was found in Glaucous-Winged Gull and Sooty Shearwater. Documenting levels of plastic ingestion in a wide array of species is necessary to gain a comprehensive understanding about the impacts of plastic pollution. We propose that those working with bird carcasses follow standard protocols to assess the levels of plastic ingestion whenever possible.
Afficher plus [+] Moins [-]Concentration of organic sun-blocking agents in seawater of beaches and coral reefs of Okinawa Island, Japan
2013
Tashiro, Yutaka | Kameda, Yutaka
The concentration of UV filters (UVFs) and UV light stabilizers (UVLSs) were measured in seawater and river water collected from sites at four beaches, two reefs, and one river on Okinawa Island, Japan. UVFs and/or UVLSs of 8–10 types were detected in beaches samples and 6–9 types were detected in reef samples. The total UVF concentrations at the beach sites were highest either in July or August with a maximum of 1.4μgL−1. The concentrations at the reef sites did not show peaks in summer and the maximum values were close to 10ngL−1. The detected UVF profiles reflected the ingredients of sunscreens used in each region. The highest UVLS concentrations at the reefs were observed not only in summer but also in June and September. The UVLS concentrations at the reefs were similar to or even higher than that at the beaches or in the river.
Afficher plus [+] Moins [-]Distribution of the genus Alexandrium (Halim) and paralytic shellfish toxins along the coastline of New South Wales, Australia
2013
Farrell, Hazel | Brett, Steve | Ajani, Penelope | Murray, Shauna
Blooms of Alexandrium species, in particular the species Alexandrium catenella, accounted for more than 50% of algal related, shellfish aquaculture harvest zone closures in New South Wales (NSW) Australia since 2005. While there are indications that species of Alexandrium are more abundant than they were formerly, there is little data available on the spatial and temporal distribution and abundance of the genus in NSW. A six and a half year dataset comprising a total of 8649 fortnightly samples from 31 estuaries spread over 2000km of NSW coastline was analysed. The greatest abundances of Alexandrium spp. were observed during the austral Spring and Summer, in estuaries in the mid and southern latitudes of the state. In identifying these high risk zones, we propose variables such as season, temperature, rainfall and estuarine flushing to be targeted in intensive site specific studies, to support the development of predictive tools for resource managers.
Afficher plus [+] Moins [-]Daily accumulation rates of marine debris on sub-Antarctic island beaches
2013
(Harry),
The worlds’ oceans contain a large but unknown amount of plastic debris. We made daily collections of marine debris stranded at two sub-Antarctic islands to establish (a) physical causes of strandings, and (b) a sampling protocol to better estimate the oceans’ plastic loading. Accumulation rates at some beaches were dependent on tide and onshore winds. Most of the 6389 items collected were plastic (Macquarie 95%, Heard 94%) and discarded or lost fishing gear comprised 22% of those plastic items. Stalked barnacles (Lepas spp.) were a regular attachment on Macquarie debris but not at Heard Island. The daily accumulation rate of plastic debris on Macquarie Island was an order of magnitude higher than that estimated from monthly surveys during the same 4months in the previous 5years. This finding suggests that estimates of the oceans’ plastic loading are an order of magnitude too low.
Afficher plus [+] Moins [-]Assessing the spatial variability, level and source of organic chemical contaminants in bivalve fishing grounds on the Galician coast (NW Spain)
2013
Polychlorinated biphenyls, organochlorine pesticides, organotin compounds and triazines were quantified in sediments and bivalves collected in four areas on the Galician coast. One or several species were analysed at each site depending on their availability, including mussels (Mytilus galloprovincialis), cockles (Cerastoderma edule), clams (Venerupis pullastra and Ruditapes decussatus) and razor shells (Ensis siliqua). The general spatial distribution of contaminants was consistent in spite of the different sources of contamination. High inter-species variability was also observed. M. galloprovincialis and V. pullastra showed the highest levels of contaminants and intra-spatial variability, which highlights them as suitable species to be used as sentinel organisms. The area of O Burgo showed some worrisome results: PCB sediment concentrations were within the range that could cause biological effects. Also the level of heptachlor observed in V. pullastra was above limits accepted on edible seafood. Finally TBT concentration in mussels correlated with concentrations causing imposex in snails.
Afficher plus [+] Moins [-]Investigations on the impact of single direct and indirect, and multiple emission–control measures on cold–season near–surface PM2.5 concentrations in Fairbanks, Alaska
2013
Mölders, Nicole
The impact of two direct (wood–burning device changeout, introduction of gas), an indirect (introduction of low–sulfur fuel) and a multiple (wood–burning device changeout plus introduction of low–sulfur fuel) emission control measure on near surface PM2.5 concentrations in Fairbanks, Alaska was examined for a cold season by WRF/Chem simulations and the 2008/09 hourly observations. The benefits for air quality would vary in persistence and the diurnal course among measures. None of these emission control measures would provide design values below the National Ambient Air Quality Standard (35µg m–3). Substituting all wood–burning by gas would reduce PM2.5 emissions by ~11% and the 2008 design value of 44.7µg m–3 to 38.9µg m–3. The estimated ~4% PM2.5 emission decrease due to changeout of noncertified by certified wood–burning devices would reduce the design value to 42.3µg m–3. The use of low–sulfur fuel in oil–fired furnaces and facilities would reduce total SO2 and PM2.5 emissions by ~23 and 15%, respectively, but provide a similar design value. The multiple emission control measure would reduce these emissions by ~36 and 19%, respectively, and the design value to 39.3µg m–3. The indirect emission control measure is most sensitive to meteorology. The efficiency of the multiple emission control measures is not generally the sum of the efficiency of the respective single measures.
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