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White lupin plants were grown in hydroponics with 0, 90 and 180 µmol L?1 Pb(II) ethylenediaminetetraacetate complex for 30 days. Pb distribution (shoot/root ratio) was 0.34 and 0.46 for both Pb treatments. In the shoots, no decrease in biomass nor in photosynthetic pigment levels and no changes in the concentrations of malondialdehyde and glutathione were detected. In the roots, malondialdehyde increased by 20%, glutathione 2–3.6 times and phytochelatin concentrations 4–5 times. The high tolerance of white lupin makes it a valuable plant for phytoremediation of Pb-contaminated soil.  相似文献   
134.
The overall resource requirements for the production of germanium wafers for III–V multi-junction solar cells applied in concentrator photovoltaics have been assessed based on up to date process information. By employing the cumulative energy demand (CED) method and the cumulative exergy extraction from the natural environment (CEENE) method the following resources have been included in the assessment: fossil resources, nuclear resources, renewable resources, land resources, atmospheric resources, metal resources, mineral resources and water resources. The CED has been determined as 216 MJ and the CEENE has been determined as 258 MJex. In addition partial energy and exergy payback times have been calculated for the base case, which entails the installation of the high concentration photovoltaics (HCPVs) in the Southwestern USA, resulting in payback times of around 4 days for the germanium wafer production. Due to applying concentration technology the germanium wafer accounts for only 3% of the overall resource consumption of an HCPV system. A scenario analysis on the electricity input to the wafer production and on the country of installation of the HCPV has been performed, showing the importance of these factors on the cumulative resource consumption of the wafer production and the partial payback times.  相似文献   
135.
Feeding ecology was analysed for the first time in the larvae of the European hake (Merluccius merluccius) to determine whether their diet and selectivity were constrained by environmental conditions and how these feeding characteristics were related to ontogeny, prey availability and visual capabilities. Larvae collected during both day and night were analysed, and it was found that feeding incidence was high, regardless of the time of day. Examination of the visual system corroborated the hypothesis that hake larvae should be able to cope with a wide range of photic conditions and to forage even at low light intensity. A clear preference for adult calanoid copepods and, especially, for Clausocalanus spp. was observed in all sizes analysed. Prey number increased with larval size, but prey size did not. This finding indicates that hake larvae behave as selective and specialist predators that consume an increasing number of prey rather than larger prey during larval growth.  相似文献   
136.
We present examples of cumulative chemical risk mapping methods developed within the NoMiracle project. The different examples illustrate the application of the concentration addition (CA) approach to pesticides at different scale, the integration in space of cumulative risks to individual organisms under the CA assumption, and two techniques to (1) integrate risks using data-driven, parametric statistical methods, and (2) cluster together areas with similar occurrence of different risk factors, respectively. The examples are used to discuss some general issues, particularly on the conventional nature of cumulative risk maps, and may provide some suggestions for the practice of cumulative risk mapping.  相似文献   
137.
Socially dominant males often signal their status to rival males and/or females. We tested the hypotheses that Lacerta monticola femoral gland secretions and copulatory plugs convey chemical information about male identity and dominance status. We estimated male dominance status by staging male–male agonistic encounters in a neutral arena. We then conducted two experiments to compare male tongue-flick behavior toward chemical stimuli consisting of cotton swabs bearing (1) deionized water (control), the lizard’s own femoral secretions, and the femoral secretions of another male and (2) phosphate-buffered saline solution (control), the lizard’s own plug products, and the plug products of another male. Results indicate that males discriminated their own femoral secretions and plugs from those of other males. They also discriminated morphological attributes of other males that were associated with dominance status based on chemical cues arising from femoral secretions and discriminated the dominance status of other males based on chemical cues arising from the plugs. Femoral secretions that convey information about male identity and dominance status may be hypothesized to function in the establishment of L. monticola dominance hierarchies through scent-marking of territories. We suggest that copulatory plugs and femoral secretions may allow males to scent-mark the female body and postulate that this behavior may influence male and female reproductive decisions under selective pressures of sperm competition.  相似文献   
138.
We studied the effects of elevated heavy metal uptake on the sperm quality and the antioxidant mechanisms of sperm and testis of red deer from a Pb mining area in Spain. Testis, liver and bone of red deer from mining (n = 21) and control (n = 20) areas were obtained from hunters and analyzed for Pb, Zn, Cu, Cd, As and Se. Testes were weighed and measured. Motility, acrosome integrity and viability and functionality of membrane were evaluated in epididymal spermatozoa. Lipid peroxidation, total glutathione, glutathione peroxidase (GPX) and superoxide dismutase (SOD) were studied in testis and spermatozoa. Deer from mined areas showed less Cu in testis, a higher testis mass and size and reduced spermatozoa membrane viability and acrosome integrity. Effects on sperm quality were associated to decreased Cu and increased Se in testis, and to decreases in the activity of SOD and GPX in testis and spermatozoa.  相似文献   
139.
Phytoremediation of metal-polluted soils can be promoted by the proper use of soil amendments and agricultural practices. A 4-year phytoremediation programme was applied to a site affected by the toxic spill of pyrite residue at Aznalcóllar (Spain) in 1998, contaminated with heavy metals (Zn, Cu, Pb, Cd) and arsenic. This consisted of active phytoremediation, using organic amendments (cow manure and compost) and lime and growing two successive crops of Brassica juncea (L.) Czern., followed by natural attenuation without further intervention. Changes in soil pH, extractable metal and As concentrations, organic carbon content and microbial biomass was evaluated. The initial oxidation of metal sulphides from pyrite residues released soluble metals and reduced soil pH to extremely acidic values (mean 4.1, range 2.0-7.0). The addition of lime (up to 64 t ha(-1)) increased soil pH to adequate values for plant growth, resulting in a significant decrease in DTPA-extractable metal concentrations in all plots. The natural attenuation phase showed also a decrease in extractable metals. Organic treatments increased the soil total organic carbon, which led to higher values of microbial biomass (11.6, 15.2 and 14.9 g kg(-1) TOC and 123, 170 and 275 microg g(-1) biomass-C in control, compost and manure plots, respectively). Active phytoremediation followed by natural attenuation, was effective for remediation of this pyrite-polluted soil.  相似文献   
140.
In an agonistic interaction, the assessment of the probable outcome of future encounters with the same individuals may be the best way of decreasing costs of fighting, but this may only be accomplished if animals are able to recognize individual conspecifics. We staged encounters between male lizards, Podarcis hispanica, to examine whether odoriferous cues are involved in rival recognition during agonistic interactions. We experimentally manipulated the odour of intruding males, creating familiar males with their own odour or bearing odours of unfamiliar males, and unfamiliar males bearing unfamiliar odours or odours of familiar males. The results showed that when familiar males were impregnated with scents from unfamiliar males, they elicited an aggressive response by resident unmanipulated males similar to that observed for a new unfamiliar male with unfamiliar odour. This suggests that resident males were unable to recognize familiar males when their own scents were removed. In contrast, responding males were less aggressive towards familiar males impregnated with their own odour and towards unfamiliar males impregnated with scents of familiar males, suggesting that when two males have already interacted, their scents become familiar for both males, and that the detection in successive encounters of the familiar scent suffices to reduce the aggressive response of territorial males. Therefore, recognition mechanisms based on chemical cues during agonistic encounters may contribute to reducing the intensity and the costs of fighting in P. hispanica and may play an important role in the organization of their social system.  相似文献   
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