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121.
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
122.
Rosa De Las Heras José Luis Rodríguez-Gil Jon San Sebastián Sauto Paz Sánchez Sánchez 《Journal of environmental science and health. Part. B》2013,48(9):567-579
ABSTRACTThe development of field-based biomarkers can allow for a more reliable assessment of the exposure of organisms to pollutants. Different sampling sites, along two streams running through an irrigable agricultural area, were selected to evaluate the effect of agrochemical load on the measured endpoints. The levels of lipid peroxidation were evaluated in several organs of Procambarus clarkii. The same method was applied to leaves of two woody species. Determining levels of MDA (malonaldehyde) by thiobarbituric acid reactive substances assay allows measuring the levels of lipid peroxidation. Differences in lipid peroxidation levels were observed in P. clarkii individuals collected at different sites; however, the patterns varied depending on the organ (when accounting for variations due to sex). The use of a MDA-gills/MDA-hepatopancreas index allowed for discrimination between reference and polluted sites. Significant differences in oxidative damage between sites were found in the leaves of Quercus rotundifolia but not in Salix sp. The lipid peroxidation of crayfish organs and holm oak leaves as a suitable biomarker of environmental pollution deserves further investigation. 相似文献
123.
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
124.
Removal of chloride from recycled cooling water is needed to reduce corrosion and prolong equipment life. Laboratory experiments have demonstrated that the ultra-high lime with aluminum (UHLA) process has the ability to achieve high chloride removal efficiency from recycled cooling water. In an effort to further understand the behavior of chloride in the UHLA process, a fundamental model of the chemical processes was developed. The purpose of this paper is to describe this equilibrium model and present values for solubility products of precipitated solids that have not been investigated previously. The model was based on PHREEQC and a new program called INVRS K was integrated with PHREEQC to calculate values of unknown or poorly defined equilibrium or kinetic constants using a Gauss-Newton nonlinear regression routine. Model predictions indicated that the results could be best described by assuming the formation of a solid solution of calcium chloroaluminate (Ca4Al2Cl2OH12), tricalcium hydroxyaluminate (Ca3Al2OH12), and tetracalcium hydroxyaluminate (Ca4Al2OH14). 相似文献
125.
126.
Quantifying species recovery and conservation success to develop an IUCN Green List of Species 下载免费PDF全文
H. Resit Akçakaya Elizabeth L. Bennett Thomas M. Brooks Molly K. Grace Anna Heath Simon Hedges Craig Hilton‐Taylor Michael Hoffmann David A. Keith Barney Long David P. Mallon Erik Meijaard E.J. Milner‐Gulland Ana S.L. Rodrigues Jon Paul Rodriguez P.J. Stephenson Simon N. Stuart Richard P. Young 《Conservation biology》2018,32(5):1128-1138
Stopping declines in biodiversity is critically important, but it is only a first step toward achieving more ambitious conservation goals. The absence of an objective and practical definition of species recovery that is applicable across taxonomic groups leads to inconsistent targets in recovery plans and frustrates reporting and maximization of conservation impact. We devised a framework for comprehensively assessing species recovery and conservation success. We propose a definition of a fully recovered species that emphasizes viability, ecological functionality, and representation; and use counterfactual approaches to quantify degree of recovery. This allowed us to calculate a set of 4 conservation metrics that demonstrate impacts of conservation efforts to date (conservation legacy); identify dependence of a species on conservation actions (conservation dependence); quantify expected gains resulting from conservation action in the medium term (conservation gain); and specify requirements to achieve maximum plausible recovery over the long term (recovery potential). These metrics can incentivize the establishment and achievement of ambitious conservation targets. We illustrate their use by applying the framework to a vertebrate, an invertebrate, and a woody and an herbaceous plant. Our approach is a preliminary framework for an International Union for Conservation of Nature (IUCN) Green List of Species, which was mandated by a resolution of IUCN members in 2012. Although there are several challenges in applying our proposed framework to a wide range of species, we believe its further development, implementation, and integration with the IUCN Red List of Threatened Species will help catalyze a positive and ambitious vision for conservation that will drive sustained conservation action. 相似文献
127.
Aseel A. Takshe Meg Huby Sofia Frantzi Jon C. Lovett 《Journal of environmental management》2010,91(4):887-896
In July 2006 a war between Lebanon and Israel resulted in severe environmental damage in Lebanon from Israeli bombing raids. An attack on the Lebanese Jiyyeh Power Plant released 15,000 tons of heavy fuel oil into the Mediterranean Sea. Remarkably, a clean-up operation was effected despite a continued state of war and lack of capacity in the Lebanese government. Civil society environmentalists played a key role in dealing with the pollution and complying with pollution-control legislation. In this study we use Q-methodology to analyse discourses on the effectiveness of pollution legislation during times of conflict using the Jiyyeh oil spill as an example. We interviewed 35 people from eight different stakeholder groups involved in environmental issues. Five distinct discourses were generated covering compensation schemes, need for new legislation, role of stakeholders during wartime and strengthening government ministries. 相似文献
128.
Stefan George Bolam Jon Barry Michaela Schratzberger Paul Whomersley Mike Dearnaley 《Environmental monitoring and assessment》2010,168(1-4):499-510
Dredged material is increasingly being regarded as a potential resource, and one of its many uses is to create and/or improve intertidal habitats (i.e. beneficial use). However, uncertainties over the longer-term environmental consequences of such schemes have, to date, limited the practice to small-scale applications in UK waters. This paper studies the macrofaunal recolonisation of fine-grained dredged material recharged concurrently at four adjacent recharge areas along the south-east coast of the UK in order to facilitate predictions regarding the recolonisation of comparable schemes and, thereby, to promote effective environmental management. During the 2-year study period, the four recharge areas were distinctly different in terms of their environmental characteristics, primarily wave exposure and bed level. These conditions resulted in different macrofaunal recolonisation rates and community structures. While the low-level, wave-sheltered area experienced rapid recolonisation, the process was delayed until 12 months post-recharge at the relatively wave-exposed areas. Bed level differences resulted in distinctly different communities in wave-sheltered areas but not under wave-exposed conditions. While we are unable to separate the effects of individual environmental variables on recolonisation, these results provide general conclusions as to the importance of environmental conditions on resulting macrofaunal communities. 相似文献
129.
130.
Population context should influence pollination success and selection on floral display in animal-pollinated plants because attraction of pollinators depends not only on the characteristics of individual plants, but also on the attractiveness of co-occurring conspecifics. The insect-pollinated herb Primula farinosa is polymorphic for inflorescence height. Natural populations may include both long-scaped plants, which present their flowers well above the soil surface, and short-scaped plants, with their flowers positioned close to the ground. We experimentally tested whether seed production in short-scaped P. farinosa varied with local morph frequency and surrounding vegetation height. In tall vegetation, short-scaped plants in polymorphic populations produced more fruit and tended to produce more seeds than short-scaped plants did in monomorphic populations. In low vegetation, population composition did not significantly affect fruit and seed output of short-scaped plants. The results suggest that long-scaped plants facilitate short-scaped plants in terms of pollinator attraction and that the facilitation effect is contingent on the height of the surrounding vegetation. The documented facilitation should contribute to the maintenance of the scape length polymorphism in ungrazed areas where litter accumulates and vegetation grows tall. 相似文献