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The objective of this study was to determine the potential for dietary transfer of sediment-associated fluoranthene from tubificid oligochaetes (Monopylephorus rubroniveus) to grass shrimp (Palaemonetes pugio). Grass shrimp, either in the presence or absence of sublethal waterborne concentrations of the metabolic inhibitor, piperonyl butoxide (PBO), were fed fluoranthene-dosed oligochaetes for 5-days. All grass shrimp bioaccumulated fluoranthene; however, bioaccumulation was 3X higher in the presence of PBO. Trophic transfer coefficients (TTCs) were 0.02 and 0.01 in the presence and absence of PBO, respectively. Following the 5-day accumulation period, shrimp in both treatments were allowed to depurate for 3 days. Depuration rates were significantly higher in PBO-exposed shrimp. These results demonstrated that sediment-associated fluoranthene can be transferred through the diet from oligochaetes to grass shrimp, and the presence of PBO enhanced fluoranthene bioaccumulation. However, the comparatively low TTCs suggest that biomagnification of fluoranthene in estuarine food webs is low. 相似文献
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Michael P. Weinstein 《Estuaries and Coasts》2007,30(2):365-370
More than ever, there is a need to integrate restoration ecology, as practiced by the scientific community, and ecological
restoration, a province that is largely, but not entirely the purview of practitioners. Success in some coastal restoration
projects is increasingly measured in the context of practioner skills and cultural goals rather than by the manifestation
of underlying ecological principles and mechanisms in the restoration process. Especially in human-dominated landscapes, restoration
practices should attempt to balance human needs with those of extant biota in a consensus based combination of restoration
ecology and ecological restoration criteria. The goal is to devise plans at the appropriate scale that allow humans and other
biota to share space and resources in an increasingly complex landscape. No matter where restoration takes place, both ecological
fidelity (in ecocentric terms) and human dimensions (in anthropocentric terms) must comprise the restoration design, but ultimately
in proportion to human density in the landscape. Without this integration, compromise, and balance, restoration will not likely
prosper in the mainstream of society. 相似文献
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Michael P. Weinstein 《Estuaries and Coasts》2009,32(6):1044-1053
Although the organizing committee for the 2007 Coastal and Estuarine Research Federation (CERF) Biennial Conference and its
international members supported the inclusion of sustainability science as a thematic element of the meeting, a preliminary
review of program abstracts, conducted by entering various combinations of key words into the conference search engine, identified
only 50 individual abstracts that incorporated one or more of the key words, or 3.8% of the 1,300 papers presented. Moreover,
only 25 abstracts (1.9%) made specific reference to the integration of the natural and social sciences in emerging coastal
research priorities. In this context, a framework is presented for incorporating the concepts of sustainable development,
sustainability science, especially for the urban coast, and human dimensions into the amalgam of future US and international
CERF research. 相似文献
35.
Profitability of fish farming can be undermined by a suite of biological constraints. Effects of these constraints on the biology of the animal, the functioning of a tissue, or the quality of the final filleted product can be detected with very sensitive hi-tech approaches, grouped by the term ‘-omics’. These -omics technologies further present powerful tools for the genetic selection of diverse traits and, as such, will contribute substantially to the future development of the aquaculture sector. Sustainability issues of importance to the industry, such as environmental impacts, use of therapeutants, fish health management and fishmeal replacement, can again be aided, at least in part, through the effective use of -omics technologies. It thus appears that -omics technologies may be a key tool for the responsible growth of intensive aquaculture in the 21st century. In this paper we review the current status of -omics technologies and the potential for application within the aquaculture industry. 相似文献
36.
Measurements of Pb isotopes in aerosols, precipitation, and size-fractionated particulate matter from the Gulf of Maine, Scotian Shelf and Labrador Sea are used to investigate the source of Pb. The 206Pb/207Pb ratio in aerosols and precipitation collected at New Castle, NH suggests that anthropogenic Pb is a mixture of US and Canadian sources. 206Pb/207Pb ratios in >53 μm particulate matter from the Gulf of Maine and Scotian Shelf slope waters are consistent with contaminant Pb inputs predominantly from US and Canadian sources, while in shelf waters 206Pb/207Pb ratios in >0.4 μm and >53 μm particles are consistent with a mixture of US and Canadian sources, as well as Pb associated with resuspended surface sediment. 206Pb/207Pb ratios in particulate matter (>0.4 μm, 10-53 μm, and >53 μm) from Labrador Sea surface waters range from 1.165 to 1.211 and are a mixture of Pb derived from ore compositions consistent with Broken Hill, Australia and southeast Missouri, US sources. 相似文献
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Tsunami Warning Centers issue rapid and accurate tsunami warnings to coastal populations by estimating the location and size of the causative earthquake as soon as possible after rupture initiation. Both US Tsunami Warning Centers have therefore been using Mwp to issue Tsunami Warnings 5–10 min after Earthquake origin time since 2002. However, because Mwp (Tsuboi et al., Bulletin of the Seismological society of America 85:606–613, 1995) is based on the far-field approximation to the P-wave displacement due to a double couple point source, we should only very carefully apply Mwp to data obtained in the near field, at distances of less than a few wavelengths from the fault. On the other hand, the surface waves from Great Earthquakes, including those that occur just offshore of populated areas, such as the 2011 Tohoku earthquake, clip seismographs located near the fault. Because the first arriving P-waves from such large events are often on scale, Mwp should provide useful information, even for these Great Earthquakes. We therefore calculate Mwp from 18 unclipped STS-1 broadband P-wave seismograms, recorded at 2–15° distance from the Tohoku epicenter to determine if Mwp can usefully estimate Mw for this earthquake, using data obtained close to the epicenter. In this case there should be a good chance to get reliable Mwp values for stations at epicentral distances of 9–10°, since the source duration for the Tohoku earthquake is less than 200 s and the time window used to estimate Mwp is 120 s in duration. Our analysis indicates that Mwp does indeed give reliable results (Mw ~ 9.1) beginning at about 11° distance from the epicenter. The values of Mwp from seismic waveforms obtained at 11–15° epicentral distance from the Mw 9.1 off the east coast of Tohuku earthquake of March 11, 2011 fell within the range 9.1–9.3, and were available within 4–5 min after origin time. Even the Mwp values of 7.7–8.4, obtained at less than 5° epicentral distance, exceed the PTWC’s threshold of Mw 7.6 for issuing a regional tsunami warning to coastal populations within 1,000 km of the epicenter, and of Mw 6.9 for issuing a local tsunami warning to the coastal populations of Hawaii. 相似文献