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961.
Ali Hosseini Justin Emrys Brown Mark Dowdall William Standring Per Strand 《Environmental monitoring and assessment》2011,173(1-4):653-667
Significant shifts in opinion regarding environmental protection from ionising radiation have resulted in the development and availability of bespoke approaches for the assessment of impacts on wildlife from radioactive contaminants. The application of such assessment methodologies to actual situations, however, remains relatively limited. This paper describes the implementation of the ERICA Integrated Approach and associated tools within the context of routine discharges of radioactive materials to a freshwater environment. The article follows the implementation through its relevant stages and discusses strengths and weaknesses of the approach in relation to the case study. For current discharge levels, 137Cs and 60Co constitute the main dose contributors to the majority of reference organisms studied, although 241Am and 3H are the main contributors for the phyto- and zooplankton categories. Patterns are observed depending on whether the reference organism is sediment-associated or not. At current discharge levels, none of the reference organisms exceeded or approached the selected screening level, and impacts on biota could be regarded as negligible. 相似文献
962.
Mercury concentrations in oligohaline wetland vegetation and associated soil biogeochemistry 总被引:1,自引:0,他引:1
Concentrations of mercury were determined in above- and below-ground tissues of dominant plant species, as well as soils, in the wetlands of Lake Maurepas, Louisiana. Indicators of wetland soil biogeochemical status, such as soil redox potential, pore-water nutrient concentrations, and pore-water total sulfides, were also determined. Total mercury concentrations in plant tissues were within the typical range for vegetation not exposed to mercury contamination. Similarly, total mercury concentrations in soils were typical of uncontaminated wetlands within this geographic region. Soil methyl mercury levels in this study are slightly lower than those reported in other studies of nearby wetlands. This may reflect the less extensive geographic sampling in this study, or the low water levels in the Lake Maurepas system immediately prior to and during this study, which would have altered soil biogeochemical status. This is corroborated by measurements of soil redox potential and soil pore-water nitrogen and sulfur constituents conducted during this study that suggest minimal sulfate reduction was occurring in surficial soils. This study indicates that the wetlands surrounding Lake Maurepas are typical of many uncontaminated oligohaline wetlands in the southeastern U.S. in regard to mercury concentrations. 相似文献
963.
The concentrations of Cu, Pb, Zn, Cd, and Ni were measured in surface and core sediments to determine their distribution characteristics and toxicity in the sediments of Lake Chaohu. The results revealed that metal concentrations in the surface sediments had a tendency to increase from the estuarine mouth to the lake center. The distribution characteristics of the five target metals were similar along the sediment profiles at each site. Principal component analysis revealed that all of the measured variables were loaded in the same component, indicating that there was a strong relationship among these measured variables, which was confirmed by the correlation analysis. Two sets of sediment quality guidelines (SQGs): simultaneously extracted metal (SEM) and acid volatile sulfides (AVS) models (including ∑SEM/AVS, ∑SEM-AVS, and ∑SEM-AVS/ f (oc)) and threshold effect level and probable effect level values were used to predict the sediment toxicity. Comparison of the results obtained using these two sets of SQGs revealed that only a small portion of the entire set was identical, while the majority of the results were different and sometimes completely contradictory. These contradictory results would cause a great deal of trouble for environment managers. More accurate and universal SQGs must be developed for environmental researchers and local environmental managers and regulators. 相似文献
964.
Santamaría J Quinonez-Diaz Mde J Lemond L Arnold RG Quanrud D Gerba C Brusseau ML 《Journal of environmental monitoring : JEM》2011,13(12):3481-3484
The objective of this study was to investigate the impact of length scale (travel distance) on the retention and transport of Cryptosporidium oocysts in a sandy soil. Long columns (1 and 2 meters) and an in situ lysimeter (4 m) were used to allow investigation of larger-scale transport under controlled conditions. Significant retention of oocysts was observed, with the magnitude of removal from solution ranging between 2 to 5 logs. While the removal was greater for longer travel distances (or residence times), the increase was not log-linear. This observation indicates that oocyst transport was not consistent with standard colloid filtration theory. The observed behavior is speculated to arise, at least in part, from intrapopulation variability in oocyst properties. The results of this study indicate that while Cryptosporidium oocysts may be expected to experience significant retention and removal during transport in sandy soil, the magnitude of retention may be less than that which would be predicted by applying standard colloid filtration theory to the results of typical short-column experiments. Thus, a fraction of the oocysts may be more mobile than anticipated and thereby pose a greater than expected risk to groundwater. 相似文献
965.
Sizmur T Tilston EL Charnock J Palumbo-Roe B Watts MJ Hodson ME 《Journal of environmental monitoring : JEM》2011,13(2):266-273
The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid restoration practices. Eisenia veneta (epigeic), Lumbricus terrestris (anecic) and Allolobophora chlorotica (endogeic) earthworms were cultivated in columns containing 900 g soil with 1130, 345, 113 and 131 mg kg(-1) of As, Cu, Pb and Zn, respectively, for up to 112 days, in parallel with earthworm-free columns. Leachate was produced by pouring water on the soil surface to saturate the soil and generate downflow. Ryegrass was grown on the top of columns to assess metal uptake into biota. Different ecological groups affected metals in the same way by increasing concentrations and free ion activities in leachate, but anecic L. terrestris had the greatest effect by increasing leachate concentrations of As by 267%, Cu by 393%, Pb by 190%, and Zn by 429% compared to earthworm-free columns. Ryegrass grown in earthworm-bearing soil accumulated more metal and the soil microbial community exhibited greater stress. Results are consistent with earthworm enhanced degradation of organic matter leading to release of organically bound elements. The degradation of organic matter also releases organic acids which decrease the soil pH. The earthworms do not appear to carry out a unique process, but increase the rate of a process that is already occurring. The impact of earthworms on metal mobility and availability should therefore be considered when inoculating earthworms into contaminated soils as new pathways to receptors may be created or the flow of metals and metalloids to receptors may be elevated. 相似文献
966.
Darbah JN Jones WS Burton AJ Nagy J Kubiske ME 《Journal of environmental monitoring : JEM》2011,13(9):2436-2442
We studied the effect of high ozone (O(3)) concentration (110-490 nmol mol(-1)) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O(3) pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O(3) exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O(3) and/or CO(2) for 12 years, were harvested. Acute O(3) damage was not uniform within the crowns of aspen suckers; it was most severe in the mature, fully expanded photosynthesizing leaves. Young expanding leaves showed no visible signs of acute O(3) damage contrary to expectations. Stomatal conductance played a primary role in the severity of acute O(3) damage as it directly controlled O(3) uptake. Maple sprouts, which had lower stomatal conductance, smaller stomatal aperture, higher stomatal density and larger leaf surface area, were tolerant of acute O(3) exposure. Moreover, elevated CO(2) did not ameliorate the adverse effects of acute O(3) dose on aspen and maple sprouts, in contrast to its ability to counteract the effects of long-term chronic exposure to lower O(3) levels. 相似文献
967.
Miklós Laczi Gergely Hegyi Márton Herényi Dorottya Kiss Gábor Markó Gergely Nagy Balázs Rosivall Eszter Szöllősi János Török 《Die Naturwissenschaften》2013,100(10):983-991
The possible integration of different sexual ornaments into a composite system, and especially the information content of such ornament complexes, is poorly investigated. Many bird species display complex plumage coloration, but whether this represents one integrated or several independent sexual traits can be unclear. Collared flycatchers (Ficedula albicollis) display melanised and depigmented plumage areas, and the spectral features (brightness and UV chroma) of these are correlated with each other across the plumage. In a 5-year dataset of male and female plumage reflectance, we examined some of the potential information content of integrated, plumage-level colour attributes by estimating their relationships to previous and current year body condition, laying date and clutch size. Females were in better condition the year before they became darker pigmented, and males in better current year condition were also darker pigmented. Female pigment-based brightness was positively, while male structurally based brightness was negatively related to current laying date. Finally, the overall UV chroma of white plumage areas in males was positively associated with current clutch size. Our results show that higher degree of pigmentation is related to better condition, while the structural colour component is associated with some aspects of reproductive investment. These results highlight the possibility that correlated aspects of a multiple plumage ornamentation system may reflect together some aspects of individual quality, thereby functioning as a composite signal. 相似文献
968.
AbdelHamid Sherihan G. Refaat Aya A. Benjamin Anthony M. Elmawardy Laila A. Elgendy Lougine A. Manolly Mark M. Elmaksoud Nada Abd Sherif Nourhan Hamdy Nadia M. 《Environmental science and pollution research international》2021,28(39):54209-54221
Environmental Science and Pollution Research - COVID-19 pandemic waves hitting worldwide result in drastic postinfection complications with interindividual variations, which raised the question for... 相似文献
969.
Han Ziming Ma Jincai Yang Ching-Hong Ibekwe Abasiofiok Mark 《Environmental science and pollution research international》2021,28(5):5575-5586
Environmental Science and Pollution Research - Complexities of biotic-abiotic interactions in soils result in the lack of integrated understanding of environmental variables that restrict the... 相似文献
970.