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1.
Gebbink WA Letcher RJ Burgess NM Champoux L Elliott JE Hebert CE Martin P Wayland M Weseloh DV Wilson L 《Environment international》2011,37(7):1175-1182
In the present study, we identified and examined the spatial trends, sources and dietary relationships of bioaccumulative perfluorinated sulfonate (PFSA; C(6), C(8), and C(10) chain lengths) and carboxylate (PFCA; C(6) to C(15) chain lengths) contaminants, as well as precursor compounds including several perfluorinated sulfonamides, and fluorotelomer acids and alcohols, in individual eggs (collected in 2008) from four gull species [glaucous-winged (Larus glaucescens), California (Larus californicus), ring-billed (Larus delawarensis) and herring (Larus argentatus) gulls] from 15 marine and freshwater colony sites in provinces across Canada. The pattern of PFSAs was dominated by perfluorooctane sulfonate (PFOS; >89% of ΣPFSA concentration) regardless of egg collection location. The highest ΣPFSA concentrations were found in the eggs collected in the urbanized areas in the Great Lakes and the St. Lawrence River area [Big Chicken Island 308 ng/g ww, Toronto Harbour 486 ng/g ww, and Ile Deslauriers (HG) 299 ng/g ww]. Also, eggs from all freshwater colony sites had higher ΣPFSA concentrations, which were significant (p<0.05) in many cases, compared to the marine sites with the exception of the Sable Island colony in Atlantic Canada off the coast of Nova Scotia. C(6) to C(15) chain length PFCAs were detected in the eggs, although the pattern was variable among the 15 sites, where PFUnA and PFTrA dominated the pattern for most colonies. Like the ΣPFSA, the highest concentrations of ΣPFCA were found in the eggs from Big Chicken Island, Toronto Harbour, Ile Deslauriers (HG), and Sable Island, although not all freshwater sites had higher concentrations compared to marine sites. Dietary tracers [δ(15)N and δ(13)C stable isotopes (SIs)] revealed that PFSA and PFCA exposure is colony dependent. SI signatures suggested that gulls from most marine colony sites were exposed to PFCs via marine prey. The exception was the Mandarte Island colony in Pacific British Columbia, where PFSA and PFCA exposure appeared to be via terrestrial and/or freshwater prey consumption. The same was true for the freshwater sites where egg SIs suggested both aquatic and terrestrial prey consumption as the source for PFC exposure depending on the colony. Both aquatic (marine and freshwater) and terrestrial prey are likely sources of PFC exposure to gulls but exposure scenarios are colony-specific. 相似文献
2.
Thiam Djiby Racine Dinar Ariel Ntuli Hebert 《Environmental Economics and Policy Studies》2021,23(1):173-210
Environmental Economics and Policy Studies - In many urban settings around the world the severity of water scarcity has induced changes in household behavior, leading to reduction in the volume of... 相似文献
3.
Use of genetic,climatic, and microbiological data to inform reintroduction of a regionally extinct butterfly
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Vlad Dincă Zsolt Bálint Raluca Vodă Leonardo Dapporto Paul D. N. Hebert Roger Vila 《Conservation biology》2018,32(4):828-837
Species reintroductions are increasingly used as means of mitigating biodiversity loss. Besides habitat quality at the site targeted for reintroduction, the choice of source population can be critical for success. The butterfly Melanargia russiae (Esper´s marbled white) was extirpated from Hungary over 100 years ago, and a reintroduction program has recently been approved. We used museum specimens of this butterfly, mitochondrial DNA data (mtDNA), endosymbiont screening, and climatic‐similarity analyses to determine which extant populations should be used for its reintroduction. The species displayed 2 main mtDNA lineages across its range: 1 restricted to Iberia and southern France (Iberian lineage) and another found throughout the rest of its range (Eurasian lineage). These 2 lineages possessed highly divergent wsp alleles of the bacterial endosymbiont Wolbachia. The century‐old Hungarian specimens represented an endemic haplotype belonging to the Eurasian lineage, differing by one mutation from the Balkan and eastern European populations. The Hungarian populations of M. russiae occurred in areas with a colder and drier climate relative to most sites with extant known populations. Our results suggest the populations used for reintroduction to Hungary should belong to the Eurasian lineage, preferably from eastern Ukraine (genetically close and living in areas with the highest climatic similarity). Materials stored in museum collections can provide unique opportunities to document historical genetic diversity and help direct conservation. 相似文献
4.
Sulfur isotopes link overwinter habitat use and breeding condition in Double-crested Cormorants. 总被引:1,自引:0,他引:1
North American Double-crested Cormorant (Phalacrocorax auritus) populations have increased greatly. Both breeding and overwintering ground factors have likely contributed to these increases. However, demonstrating how overwintering conditions may affect breeding birds has not been possible because of the difficulty in linking breeding birds to their wintering grounds. Here, we demonstrate the utility of stable sulfur isotopes to elucidate overwintering habitat use by cormorants breeding on Lake Erie. Sulfur isotopes in feathers grown on overwintering grounds provided insights into the degree to which birds used freshwater vs. marine environments. The proportion of birds utilizing freshwater habitats increased through time. This change may have reflected increases in freshwater aquaculture (i.e., catfish) in the U.S. south. Examination of body condition in birds returning to breed on Lake Erie indicated that those individuals that solely used marine habitats for at least a portion of the overwintering period were in poorer condition than birds using freshwater. Enhanced foraging opportunities at aquaculture facilities may improve the fitness of individuals that have returned to breed after overwintering at such locations. This study is the first to demonstrate a linkage between overwinter habitat use and breeding ground parameters in Double-crested Cormorants. These results underscore that factors throughout the Mississippi flyway are likely acting together to regulate cormorant populations. 相似文献
5.
Robin C. Puett Andrew B. Lawson Allan B. Clark James R. Hebert Martin Kulldorff 《Environmental and Ecological Statistics》2010,17(3):303-316
Many statistical tests have been developed to assess the significance of clusters of disease located around known sources
of environmental contaminants, also known as focused disease clusters. The majority of focused-cluster tests were designed
to detect a particular spatial pattern of clustering, one in which the disease cluster centers around the pollution source
and declines in a radial fashion with distance. However, other spatial patterns of environmentally related disease clusters
are likely given that the spatial dispersion patterns of environmental contaminants, and thus human exposure, depend on a
number of factors (i.e., meteorology and topography). For this study, data were simulated with five different spatial patterns
of disease clusters, reflecting potential pollutant dispersion scenarios: (1) a radial effect decreasing with increasing distance,
(2) a radial effect with a defined peak and decreasing with distance, (3) a simple angular effect, (4) an angular effect decreasing
with increasing distance and (5) an angular effect with a defined peak and decreasing with distance. The power to detect each
type of spatially distributed disease cluster was evaluated using Stone’s Maximum Likelihood Ratio Test, Tango’s Focused Test,
Bithell’s Linear Risk Score Test, and variations of the Lawson–Waller Score Test. Study findings underscore the importance
of considering environmental contaminant dispersion patterns, particularly directional effects, with respect to focused-cluster
test selection in cluster investigations. The effect of extra variation in risk also is considered, although its effect is
not substantial in terms of the power of tests. 相似文献
6.
Deirdre J. Semeyn Carolyn C. Cush Kerri M. Scolardi Jennifer Hebert Justin D. McBride Denis Grealish John E. Reynolds 《Journal of Coastal Conservation》2011,15(4):573-583
Conservation and management of the endangered Florida manatee is often centered on reducing mortality caused by watercraft
collisions. Lee County, Florida, has led the state in watercraft-related mortality for eight of the last 10 years. This county
is of particular concern as it contains important habitat for manatees, including extensive feeding grounds and an artificial
warm-water refuge where more than 900 manatees have been recorded on a single day. Distributional aerial surveys were conducted
from April 2007 through April 2009 over Lee County waters. Surveys yielded higher numbers of manatees than previously observed
in this area. Using GIS methodology, kernel density analysis illustrated seasonal changes in distribution patterns and highlighted
areas where manatees were most densely clustered. For example, during summer months, manatees were widely distributed throughout
the survey area, with high-density areas associated with seagrass beds. During winter months, manatees were densely clustered
at warm-water sites and over feeding grounds within close distance of these sites. These seasonal distribution patterns coincide
well with speed zone designations. Counts and distributions of manatees were made available, almost immediately if necessary,
to local marine law enforcement in an attempt to focus resources toward reducing manatee-watercraft collisions. Future studies
should implement similar communication strategies to improve conservation efforts. 相似文献
7.
DNA barcoding of Pacific Canada’s fishes 总被引:1,自引:0,他引:1
Dirk Steinke Tyler S. Zemlak James A. Boutillier Paul D. N. Hebert 《Marine Biology》2009,156(12):2641-2647
DNA barcoding—sequencing a standard region of the mitochondrial cytochrome c oxidase 1 gene (COI)—promises a rapid, accurate means of identifying animals to a species level. This study establishes that
sequence variability in the barcode region permits discrimination of 98% of 201 fish species from the Canadian Pacific. The
average sequence variation within species was 0.25%, while the average distance separating species within genera was 3.75%.
The latter value was considerably lower than values reported in other studies, reflecting the dominance of the Canadian fauna
by members of the young and highly diverse genus Sebastes. Although most sebastids possessed distinctive COI sequences, four species did not. As a partial offset to these cases, the
barcode records indicated the presence of a new, broadly distributed species of Paraliparis and the possibility that Paraliparis pectoralis is actually a species pair. The present study shows that most fish species in Pacific Canadian waters correspond to a single,
tightly cohesive array of barcode sequences that are distinct from those of any other species, but also highlights some taxonomic
issues that need further investigation. 相似文献
8.
Gebbink WA Letcher RJ Hebert CE Chip Weseloh DV 《Journal of environmental monitoring : JEM》2011,13(12):3365-3372
In this study, temporal trends and patterns of major C(4) to C(15) chain length PFCAs and PFSAs and some sulfonamide, fluorotelomer acid and alcohol precursors were determined in herring gull (Larus argentatus) egg pools. Samples were analyzed from fifteen collection years including 1990 and all years from 1997 to 2010, and from seven colonies located throughout the Great Lakes, ranging from remote to highly urbanized areas. Other than at the Toronto Harbour colony, the slopes of ∑PFSA concentrations (C(6), C(8), and C(10)) versus time were negative indicating general declines between 1990 and 2010. PFOS was the dominant PFSA regardless of colony or year, ranging from 80 to 99% of ∑PFSA. For ∑PFCA (C(8)-C(15)), slopes of concentrations versus time were generally positive with 4 of 7 colonies showing statistically significant (p < 0.05) increases in levels through time. Individual PFCAs showed similar increasing trends except for PFOA. Regardless of colony, the PFCA pattern was dominated by the C(10) to C(13) PFCAs. Consistent with the PFOS declines, concentrations of the PFOS precursor, PFOSA, declined at most colonies between 1990 and 2006 and post-2006 concentrations were below detection limits. Declining concentrations of the C(8) PFCs, PFOS, PFOA and PFOSA, were consistent with the phase out in 2002 by the 3M Company in North America of all of C(8) PFC-related chemistry products. Increasing production volumes of fluorotelomer based compounds, and degradation of these compounds to PFCAs may explain increasing trends of PFCAs in gull eggs. Dietary changes as measured by carbon and nitrogen stable isotopes, showed minimal relationships to PFC levels in gull eggs, which indicates the complexity of aquatic and terrestrial food of gulls and sources of PFCs. 相似文献
9.
Hebert GN Odom MA Craig PS Dick DL Strauss SH 《Journal of environmental monitoring : JEM》2002,4(1):90-95
The determination of sub-ppm concentrations of aqueous perfluoroalkylsulfonate (PFSt) anions, including perfluorooctylsulfonate (PFOS), has been accomplished with a relatively simple mass spectrometric procedure that does not require extraction of the analytes into an organic solvent or a chromatographic separation prior to injection into the negative-ion electrospray ionization mass spectrometer. Sample pretreatment was minimized and consisted of dilution of the aqueous samples of groundwater, surface water, tap water, and distilled water with acetonitrile, addition of dodecylsulfate (DDS) as an internal standard, and, in some cases, addition of known amounts of perfluorobutylsulfonate (PFBS) or PFOS for standard-addition experiments. The linear-response range for PFOS is 25.0 microg L(-1) to 2.5 mg L(-1). The lower limit of this range is three orders of magnitude lower than an equally straightforward chromatographic method. The relative errors for standard aqueous solutions containing only 25.0 microg L(-1) and 2.5 mg L(-1) PFOS are +/- 14% and +/- 7%, respectively, with 133 microg L(-1) DDS as the internal standard. The detection limit and quantification limit for PFOS in these standards are 5.0 microg L(-1) and 25.0 microg L(-1), respectively. Six different PFS anions, containing three to eight carbon atoms, were identified and quantified in an aqueous film-forming foam (AFFF) formulation using the method of standard additions. Two alkylsulfate anions and two perfluoroalkylcarboxylate anions were also identified in the AFFF formulation. 相似文献
10.
Comparative phylogeography of marine cladocerans 总被引:1,自引:0,他引:1
We examined the population genetics of six species of marine cladocerans, using a ~600 bp fragment of the cytochrome oxidase
subunit I gene sequence. Phylogenetic analysis revealed significant intraspecific, semi-allopatric phylogenetic breaks in
four out of five species belonging to the Podonidae, supporting an ancient radiation and oceanic expansion for this group.
By contrast, Penilia
avirostris (Sididae) displayed no phylogeographic structure across a global sampling, suggesting a recent worldwide expansion. Our results
also show a transoceanic distribution of identical or very similar haplotypes in several species of marine Cladocera, which
may be interpreted as either natural transport or evidence of recent anthropogenic transport. If the latter is the case, marine
cladocerans represent one of the first genetically documented cases of exotic or invasive marine zooplankton, likely an underreported
group.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Sequence data from this article have been deposited with the EMBL/GenBank Data Libraries under accession nos. EU675871–EU675924. 相似文献