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71.
Barnett A. Rattner Jennifer L. Pearson Nancy H. Golden Jonathan B. Cohen R. Michael Erwin Mary Ann Ottinger 《Environmental monitoring and assessment》2000,63(1):131-142
In order to examine the condition of biota in Atlantic coast estuaries, "Contaminant Exposure and Effects—Terrestrial Vertebrates" database (CEE-TV) has been compiled through computerized search of published literature, review of existing databases, and solicitation of unpublished reports from conservation agencies, private groups, and universities. Summary information has been entered into the database, including species, collection date (1965–present), site coordinates, estuary name, hydrologic unit code, sample matrix, contaminant concentrations, biomarker and bioindicator responses, and reference source, utilizing a 98-field character and numeric format. Currently, the CEE-TV database contains 3699 geo-referenced records representing 190 vertebrate species and >140,000 individuals residing in estuaries from Maine through Florida. This relational database can be directly queried or imported into a Geographic Information System to examine spatial patterns, identify data gaps and areas of concern, generate hypotheses, and focus ecotoxicological field assessments. Information on birds made up the vast majority (83%) of the database, with only a modicum of data on amphibians (<0.1%). Of the >75,000 chemical compounds in commerce, only 118 commonly measured environmental contaminants were quantified in tissues of terrestrial vertebrates. There were no CEE-TV data records in 15 of the 67 estuaries located along the Atlantic coast and Florida Gulf coast. The CEE-TV database has a number of potential applications including focusing biomonitoring efforts to generate critically needed ecotoxicological data in the numerous "gaps" along the coast, reducing uncertainty about contaminant risk, identifying areas for mitigation, restoration or special management, and ranking ecological conditions of estuaries. 相似文献
72.
Snezana Dragović Brenda J. Howard Jane A. Caborn Catherine L. Barnett Nevena Mihailović 《Environmental monitoring and assessment》2010,166(1-4):677-686
Few data are available to quantify the transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates to facilitate estimation of the internal dose to such biota in models used to assess radiation exposure. To enhance the available data, activity concentrations of 137Cs, 40K, 90Sr, 239?+?240Pu, 241Am, 235U and 238U were measured in ants (Formicidae) and corresponding undisturbed soil collected from the Zlatibor mountain in Serbia and ant/soil concentration ratios (CR) calculated. The 241Am concentration ratios for ants were fourfold higher than those calculated for ants in a previous study whereas they are similar to the more numerous data previously reported for a range of detritivorous invertebrates in other studies. CR values for 137Cs in ants were similar to the few other reported values and slightly lower than those for a range of detritivorous invertebrates. Those for 239?+?240Pu were slightly higher than those for ants in two other studies but they were close to upper limit of a range of data reported for detritivorous invertebrates. All the CR values will be included in a future revision of the ERICA Tool database and will particularly improve the information available for uranium. 相似文献
73.
Maturity,fecundity, and reproductive cycle of the spotted ratfish, <Emphasis Type="Italic">Hydrolagus colliei</Emphasis> 总被引:1,自引:1,他引:0
Lewis A. K. Barnett Ryan L. Earley David A. Ebert Gregor M. Cailliet 《Marine Biology》2009,156(3):301-316
Size at maturity, fecundity, and reproductive periodicity were estimated for the spotted ratfish, Hydrolagus colliei (Lay and Bennett, 1839), off the coast of California, Oregon, and Washington. Maximum body size and size at median maturity
were greater for females than males. Skeletal muscle concentrations of the steroid hormones testosterone (T) and estradiol
(E2) predicted similar, but slightly smaller sizes at maturity than the morphological criterion. Stage of maturity for males
was estimated identically using internal organs or external secondary sexual characters, thus allowing non-lethal maturity
assessments. Size at median maturity was greater north of Point Conception for females, and north of Cape Mendocino for males.
Peak parturition occurred from May to October, with increased concentrations of E2 in skeletal muscle of females correlating with ovarian recrudescence during November to February. No significant seasonal
trends in female T were apparent, but mean female 11-ketotestosterone (11KT) was 300% greater in April than any other month
during the parturition season. There was a marginal evidence for increased number and size of ova with maternal size. Extrapolation
of the hypothesized 6 to 8-month egg-laying season to observed mean parturition rates of captive specimens yielded an estimated
annual fecundity of 19.5–28.9 egg cases. Differences in fecundity among higher taxonomic classifications of chondrichthyans
were detected with chimaeriform fishes more fecund than lamniform, myliobatiform, squaliform, and rhinobatiform fishes, and
less fecund than rajiform fishes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
74.
Regional Environmental Change - This article presents historic energy profiles in order to understand the changing roles of three critical energy flows in eastern Canadian agroecosystems. The first... 相似文献
75.
Emmanuel K. Mbaru Christina C. Hicks Georgina G. Gurney Joshua E. Cinner 《Conservation biology》2021,35(5):1417-1425
Many conservation interventions are hypothesized to be beneficial for both the environment and people's well-being, but this has rarely been tested rigorously. We examined the effects of adoption or nonadoption of a conservation intervention on 3 dimensions of people's well-being (material, relational, and subjective) over time. We focused on a fisheries bycatch management initiative intended to reduce environmental externalities associated with resource extraction. We collected panel data from fishers (n = 250) in villages with (adopters and nonadopters) and without (control) the conservation intervention 3 times over 2 years. We found no evidence that adoption reduced any of the 3 dimensions of well-being in the local populations affected by the intervention. There were modest improvements in material (t = –1.58) and subjective livelihood well-being (p = 0.04) for adopters relative to nonadopters over time. The variations in well-being experiences (in terms of magnitude of change) among adopters, nonadopters, and controls across the different domains over time affirmed the dynamic and social nature of well-being. 相似文献
76.
Adaptive introgression as a resource for management and genetic conservation in a changing climate 下载免费PDF全文
Current rates of climate change require organisms to respond through migration, phenotypic plasticity, or genetic changes via adaptation. We focused on questions regarding species’ and populations’ ability to respond to climate change through adaptation. Specifically, the role adaptive introgression, movement of genetic material from the genome of 1 species into the genome of another through repeated interbreeding, may play in increasing species’ ability to respond to a changing climate. Such interspecific gene flow may mediate extinction risk or consequences of limited adaptive potential that result from standing genetic variation and mutation alone, enabling a quicker demographic recovery in response to changing environments. Despite the near dismissal of the potential benefits of hybridization by conservation practitioners, we examined a number of case studies across different taxa that suggest gene flow between sympatric or parapatric sister species or within species that exhibit strong ecotypic differentiation may represent an underutilized management option to conserve evolutionary potential in a changing environment. This will be particularly true where advanced‐generation hybrids exhibit adaptive traits outside the parental phenotypic range, a phenomenon known as transgressive segregation. The ideas presented in this essay are meant to provoke discussion regarding how we maintain evolutionary potential, the conservation value of natural hybrid zones, and consideration of their important role in adaptation to climate. 相似文献
77.
Joshua A. Vance Norse B. Angus James T. Anderson 《Environmental monitoring and assessment》2013,185(9):7739-7748
Construction of man-made objects such as roads and bridges may have impacts on wildlife depending on species or location. We investigated songbirds and small mammals along the Ohio River, WV, USA at a new bridge both before and after construction and at a bridge crossing that was present throughout the study. Comparisons were made at each site over three time periods (1985–1987 [Phase I] and 1998–2000 [Phase II] [pre-construction], 2007–2009 [Phase III] [post-construction]) and at three distances (0, 100, 300 m) from the bridge or proposed bridge location. Overall, 70 songbirds and 10 small mammals were detected during the study. Cliff swallows (Petrochelidon pyrrhonota) and rock pigeons (Columba livia) showed high affinity for bridges (P?<?0.05). Combined small mammal abundances increased between Phases I and II (P?<?0.05), but did not differ between Phases II and III (P?>?0.05). Species richness and diversity for songbirds and small mammals did not differ before and after bridge construction (P?>?0.05). We found that most species sampled did not respond to the bridge crossing, and believe that the bridge is not causing any measurable negative density impacts to the species we investigated. The new bridge does provide habitat for exotic rock pigeons that are adjusted to man-made structures for nesting. 相似文献
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