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Application of macrobenthos functional groups to estimate the ecosystem health in a semi-enclosed bay Полный текст
2013
Peng, Shitao | Zhou, Ran | Qin, Xuebo | Shi, Honghua | Ding, Dewen
In this study, the functional group concept was first applied to evaluate the ecosystem health of Bohai Bay. Macrobenthos functional groups were defined according to feeding types and divided into five groups: a carnivorous group (CA), omnivorous group (OM), planktivorous group (PL), herbivorous group (HE), and detritivorous group (DE). Groups CA, DE, OM, and PL were identified, but the HE group was absent from Bohai Bay. Group DE was dominant during the study periods. The ecosystem health was assessed using a functional group evenness index. The functional group evenness values of most sampling stations were less than 0.40, indicating that the ecosystem health was deteriorated in Bohai Bay. Such deterioration could be attributed to land reclamation, industrial and sewage effluents, oil pollution, and hypersaline water discharge. This study demonstrates that the functional group concept can be applied to ecosystem health assessment in a semi-enclosed bay.
Показать больше [+] Меньше [-]Incidence of plastic fragments among burrow-nesting seabird colonies on offshore islands in northern New Zealand Полный текст
2013
Buxton, Rachel T. | Currey, Caitlin A. | Lyver, Philip O’B. | Jones, Christopher J.
Marine plastic pollution is ubiquitous throughout the world’s oceans, and has been found in high concentrations in oceanic gyres of both the northern and southern hemispheres. The number of studies demonstrating plastic debris at seabird colonies and plastic ingestion by adult seabirds has increased over the past few decades. Despite the recent discovery of a large aggregation of plastic debris in the South Pacific subtropical gyre, the incidence of plastics at seabird colonies in New Zealand is unknown. Between 2011 and 2012 we surveyed six offshore islands on the northeast coast of New Zealand’s North Island for burrow-nesting seabird colonies and the presence of plastic fragments. We found non-research related plastic fragments (0.031pieces/m2) on one island only, Ohinau, within dense flesh-footed shearwater (Puffinus carneipes) colonies. On Ohinau, we found a linear relationship between burrow density and plastic density, with 3.5 times more breeding burrows in areas with plastic fragments found. From these data we conclude that plastic ingestion is a potentially a serious issue for flesh-footed shearwaters in New Zealand. Although these results do not rule out plastic ingestion by other species, they suggest the need for further research on the relationship between New Zealand’s pelagic seabirds and marine plastic pollution.
Показать больше [+] Меньше [-]Assessment of metal contamination in surface sediments from Zhelin Bay, the South China Sea Полный текст
2013
Wang, Zhao-Hui | Feng, Jie | Jiang, Tao | Gu, Yang-Guang
Metals and biogenic elements were analyzed from surface sediments collected from Zhelin Bay in the South China Sea in December 2008. The high concentrations of TOC, TN and BSi indicate the high nutrient level and diatom productivity in Zhelin Bay. The concentrations of metals were generally far lower than the effects-range-low (ERL) values that define pollutant levels. Enrichment factors (EF) and geoaccumulation indices (Igeo) suggest there are pollution levels of Cd, Cu and Zn at some stations. As, Cu, and Pb are potentially biotoxic in some stations. Correlation and principal component analyses indicate that most of the metals primarily originate from natural sources, and from maricultural activities as well. Mariculture contributes considerable Cd and Cu contamination. As and Pb comes primarily from combustion of gasoline and diesel fuel by ships.
Показать больше [+] Меньше [-]Mercury profiles in surface sediments from ten bays along the coast of Southern China Полный текст
2013
Xu, Weihai | Yan, Wen | Huang, Weixia | Chen, Zhong | Wang, Shuhong | Miao, Li | Zhong, Lifeng | Chen, Han
Spatial and temporal variations of mercury (Hg) were investigated from ten representative bays along the coast of Southern China. The total Hg (THg) in surface sediments varied widely with concentrations from 25 to 264ng/g. As a whole, Hg pollution in several bays occupied by busy sea traffic and industrial activities, such as Shantou (ST) Bay and Dapeng (DP) Bay were remarkably more serious than others, which reflected the direct effects of anthropogenic activities around the coastal areas. Hg variations in sediment cores clearly display upcore rising trend which obviously correlates with the trend of economic development and urbanization in the last five decades. No significant correlations were found between Hg and organic matter and particle size, suggesting that the distribution of Hg is not fully controlled by these variables.
Показать больше [+] Меньше [-]Temporal changes in carbon and nitrogen stable isotope ratios of macrozoobenthos on an artificial tidal flat facing a hypertrophic canal, inner Tokyo Bay Полный текст
2013
Kanaya, Gen | Nakamura, Yasuo | Koizumi, Tomoyoshi | Yamada, Katsumasa | Koshikawa, Hiroshi | Kohzu, Ayato | Maki, Hideaki
Temporal changes in benthic food web structure were analyzed in an artificial tidal flat in inner Tokyo Bay, Japan, using carbon and nitrogen stable isotope ratios (δ13C and δ15N). Microphytobenthos were the most important food sources of macrozoobenthos, due to high microphytobenthic biomass on the tidal flat, while phytoplankton in canal water (canal POMPP), terrestrial materials from urban surface runoff (canal POMTM), and marsh plants were less important. Dietary contribution of microphytobenthos was highest in April to June, while decreased towards December owing to the supply of canal POMPP and canal POMTM following red tides and heavy rainfall events in summer to fall. Temporal changes in δ15N (Δδ15N) of consumer corresponded well to the 15N-enrichment in canal POMPP in summer. A meta-analysis showed that the consumer-Δδ15N was considerably larger in inner Tokyo Bay than those in other estuaries, which may be a specific characteristic of benthic food web in highly urbanized estuaries.
Показать больше [+] Меньше [-]Spatial distribution and historical input of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediments from a subtropical estuary (Guaratuba Bay, SW Atlantic) Полный текст
2013
Combi, Tatiane | Taniguchi, Satie | Figueira, Rubens Cesar Lopes | Mahiques, Michel Michaelovitch de | Martins, César C.
This study evaluated the occurrence and distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in 22 surface sediment samples and one core collected in Guaratuba Bay, a large and well-preserved estuary in Southern Atlantic, Brazil. The concentration of PCBs in the superficial sediment samples ranged from <LQ (below the limit of quantification) to 5.62ngg−1, while the concentration of OCPs ranged from <LQ to 0.74ngg−1. The spatial distribution of the organochlorine compounds (OCs) suggested that the sources of these contaminants are located outside the bay and are related to human activities on the margins of the two main rivers that discharge in the region. The OCs in the sediment core ranged from <LQ to 0.52ngg−1 and from <LQ to 1.52ngg−1 for PCBs and OCPs, respectively. Despite their usage worldwide, the low concentrations of OCs in Guaratuba Bay suggest low input levels, which may represent the background levels for this region.
Показать больше [+] Меньше [-]The measurement of gamma-emitting radionuclides in beach sand cores of coastal regions of Ramsar, Iran using HPGe detectors Полный текст
2013
Tari, Marziyeh | Moussavi Zarandi, Sayyed Ali | Mohammadi, Kheirollah | Zare, Mohammad Reza
Radionuclides which present in different beach sands are sources of external exposure that contribute to the total radiation exposure of human. 226Ra, 235U, 232Th, 40K and 137Cs analysis has been carried out in sand samples collected at six depth levels, from eight locations of the northern coast of Iran, Ramsar, using high-resolution gamma-ray spectroscopy. The average Specific activities of natural radionuclides viz., 226Ra, 235U, 232Th, 40K and 137Cs, in the 0–36cm depth sand were found as: 19.2±0.04, 2.67±0.17, 17.9±0.06, 337.5±0.61 and 3.35±0.12 Bqkg−1, respectively. The effects of organic matter content and pH value of sand samples on the natural radionuclide levels were also investigated. Finally, the measured radionuclide concentrations in the Ramsar beach were compared with the world average values, as reported by UNSCEAR (2000). None of the studied beaches were considered as a radiological risk.
Показать больше [+] Меньше [-]Baseline metals pollution profile of tropical estuaries and coastal waters of the Straits of Malacca Полный текст
2013
Looi, Ley Juen | Ahmad Zaharin Aris, | Wan Johari, Wan Lutfi | Md. Yusoff, Fatimah | Hashim, Zailina
The status report on metal pollution in tropical estuaries and coastal waters is important to understand potential environmental health hazards. Detailed baseline measurements were made on physicochemical parameters (pH, temperature, redox potential, electrical conductivity, salinity, dissolved oxygen, total dissolved solid), major ions (Na, Ca, Mg, K, HCO3, Cl, SO4 and NO3) and metals concentrations (27Al, 75As, 138Ba, 9Be, 111Cd, 59Co, 63Cu, 52Cr, 57Fe, 55Mn, 60Ni, 208Pb, 80Se, 66Zn) at estuaries and coastal waters along the Straits of Malacca. Principal component analysis (PCA) was employed to reveal potential pollution sources. Seven principal components were extracted with relation to pollution contribution from minerals-related parameters, natural and anthropogenic sources. The output from this study will generate a profound understanding on the metal pollution status and pollution risk of the estuaries and coastal system.
Показать больше [+] Меньше [-]Biogeochemical characterization of MC252 oil:sand aggregates on a coastal headland beach Полный текст
2013
Urbano, Marilany | Elango, Vijaikrishnah | Pardue, John H.
MC252 oil:sand aggregates, termed surface residue balls (SRBs), were sampled for physical, chemical and microbial characteristics from different tidal zones on a coastal headland beach in Louisiana, USA. Supratidal SRBs were smaller, had low moisture content, and salinities that were <2ppt. Intertidal SRBs were hypersaline and had higher N and sulfate concentrations, consistent with regular tidal inundation. Crude oil components were highest in the intertidal “oil mat” SRBs with C1- and C2-phenanthrenes, C2- and C3-dibenzothiophenes comprising the majority of the PAH concentrations. In the other SRB categories, PAHs and alkanes were depleted and profiles were skewed toward higher molecular weight compounds. Oxygen microelectrode measurements demonstrated that saturated O2 is present immediately after wetting, but O2 consumption in the interior of the aggregate occurs after a few days. Microbial populations varied with position on the beach but sequences similar to known PAH-degrading taxa (Mycobacterium sp. and Stenotrophomonas sp.) were observed.
Показать больше [+] Меньше [-]Ingestion of plastic marine debris by Common and Thick-billed Murres in the northwestern Atlantic from 1985 to 2012 Полный текст
2013
Bond, Alexander L. | Provencher, Jennifer F. | Elliot, Richard D. | Ryan, Pierre C. | Rowe, Sherrylynn | Jones, Ian L. | Robertson, Gregory J. | Wilhelm, Sabina I.
Plastic ingestion by seabirds is a growing conservation issue, but there are few time series of plastic ingestion with large sample sizes for which one can assess temporal trends. Common and Thick-billed Murres (Uria aalge and U. lomvia) are pursuit-diving auks that are legally harvested in Newfoundland and Labrador, Canada. Here, we combined previously unpublished data on plastic ingestion (from the 1980s to the 1990s) with contemporary samples (2011–2012) to evaluate changes in murres’ plastic ingestion. Approximately 7% of murres had ingested plastic, with no significant change in the frequency of ingestion among species or periods. The number of pieces of plastic/bird, and mass of plastic/bird were highest in the 1980s, lowest in the late 1990s, and intermediate in contemporary samples. Studying plastic ingestion in harvested seabird populations links harvesters to conservation and health-related issues and is a useful source of large samples for diet and plastic ingestion studies.
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