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821.
A. Breccia E. Gattavecchia A.M. Di Pietra G. Albonetti 《Journal of environmental science and health. Part. B》2013,48(4):361-367
Abstract This communication describes the metabolic pathways of selenium containing compounds such as, sodium selenite (75Se), o‐methyl‐75Se‐cinnamic acid and 75Se‐1‐flavone, by the plant Brasaica Oleracea to elucidate their role in selenium flavonoid biosynthesis. 相似文献
822.
Abstract: The goal of this research was to measure the effect of a print-based interpretive program on acceptance by U.S. Coast Guard personnel of an endangered-species protection program. We used a within-subjects design to measure changes in eight survey items measuring beliefs about endangered species. There were significant changes in three items. The initial attitude toward endangered species was a strong predictor of subsequent response in a "regression to the mean effect" in which the least change was found in subjects with the highest initial scores on attitude items. Our results suggest that the print-based program was effective at changing the most highly targeted attitudes, but had little effect on more general attitudes. 相似文献
823.
Spider monkeys (Ateles spp.) live in social groups that exhibit high levels of fission–fusion dynamics, in which group members form subgroups of varying sizes and compositions. Within these fluid societies, how individuals establish contact with dispersed group members with whom they might choose to associate remains unclear. Long-range vocalizations might facilitate interactions between group members and provide a means of social coordination in fission–fusion societies. We evaluated this possibility for one spider monkey vocalization, the loud call, by examining calling behavior, the relationship between loud calls and changes in subgroup size, and the response of individuals to distant calls and playback experiments in a single study group. We found that 82 % of loud calls were emitted within 30 min of a call from a different location, suggesting that individuals frequently emit loud calls in response to the calls of distant group members. Subgroups that emitted loud calls, especially those that responded to distant calls, were much more likely to experience an increase in subgroup size within an hour after calling than those that did not. Animals also approached distant loud calls more than they avoided or ignored these calls. Finally, playbacks of male calls demonstrated that females respond preferentially to the calls of some individuals over others. Taken together, these results provide support for the hypothesis that spider monkey loud calls function to facilitate and initiate interactions between dispersed group members and suggest that vocal signals can play an important role in influencing social interactions in fission–fusion societies. 相似文献
824.
Effects of habitat and landscape fragmentation on humans and biodiversity in densely populated landscapes 总被引:3,自引:0,他引:3
Manuela Di Giulio Rolf Holderegger Silvia Tobias 《Journal of environmental management》2009,90(10):2959-2968
Landscape fragmentation has often been seen as an only ecological problem. However, fragmentation also has a societal perspective, namely, in how humans perceive landscape fragmentation and in how landscape fragmentation potentially influences human well-being. These latter aspects have rarely been addressed so far. The inter-relationship of ecological and human dimensions of landscape fragmentation becomes especially evident when looking at the landscape where most people in industrial countries live, namely in suburban and urban areas. In these areas, landscape planners and environmental managers are confronted with the problem that landscapes should fullfil various functions, often with conflicting goals, e.g. nature reserves to enhance species richness vs. recreational areas for city-dwellers. We reviewed the ecological and sociological literature relevant for fragmentation in suburban and urban landscapes. In an interdisciplinary approach, we evaluated whether there are similarities and dissimilarities between the ecological and the human aspects of landscape fragmentation. We found important similarities. An example is that for both, humans and biodiversity, the loss of semi-natural areas has more drastic effects than the fragmentation of these areas per se. However, there are also relevant differences. We concluded that in densely populated landscapes a shift from responsive planning to an intentional design of environments is therefore needed. 相似文献
825.
826.
Di Gregorio S Barbafieri M Lampis S Sanangelantoni AM Tassi E Vallini G 《Chemosphere》2006,63(2):293-299
The process of EDTA-assisted lead phytoextraction from the Bovisa (Milan, Italy) brownfield soil was optimized in microcosms vegetated with Brassica juncea. An autochthonous plant growth-promoting rhizobacterium (PGPR), Sinorhizobium sp. Pb002, was isolated from the rhizosphere of B. juncea grown on the Pb-contaminated soil in presence of 2 mM EDTA. The strain was augmented (10(8) CFU g(-1) soil) in vegetated microcosms to stimulate B. juncea biomass production and, hence, its phytoextraction potential. Triton X-100 was also added to microcosms at 5 and 10 times the critical micelle concentration (cmc) to increase the permeability of root barriers to the EDTA-Pb complexes. Triton X-100 amendment determined an increase in Pb concentration within plant tissues. However it contextually exerted a phytotoxic effect. Sinorhizobium sp. Pb002 augmentation was crucial to plant survival in presence of both bioavailable lead and Triton X-100. The combination of the two treatments produced up to 56% increase in the efficiency of lead phytoextraction by B. juncea. The effects of these treatments on the structure of the soil bacterial community were evaluated by 16S rDNA denaturing gradient gel electrophoresis (DGGE). 相似文献
827.
Ceria nanoparticles supported on aligned carbon nanotubes (CeO(2)/ACNTs), a novel adsorbent for Cr(VI) from drinking water, were prepared by chemical reaction of CeCl(3) with NaOH in aligned carbon nanotube solution and subsequent heat treatment. The best Cr(VI) adsorption effect of CeO(2)/ACNTs occurs at a pH range of 3.0-7.4. The largest adsorption capacity of CeO(2)/ACNTs reaches 30.2 mg g(-1) at an equilibrium Cr(VI) concentration of 35.3 mg l(-1) at pH 7.0. The experiment results suggest that CeO(2)/ACNTs have great potential applications in environmental protection. 相似文献
828.
Climate change affects the productivity of agricultural ecosystems. Farmers cope with climate change based on their perceptions of changing climate patterns. Using a case study from the Middle Yarlung Zangbo River Valley, we present a new research framework that uses questionnaire and interview methods to compare local farmers’ perceptions of climate change with the adaptive farming strategies they adopt. Most farmers in the valley believed that temperatures had increased in the last 30 years but did not note any changes in precipitation. Most farmers also reported sowing and harvesting hulless barley 10–15 days earlier than they were 20 years ago. In addition, farmers observed that plants were flowering and river ice was melting earlier in the season, but they did not perceive changes in plant germination, herbaceous vegetation growth, or other spring seasonal events. Most farmers noticed an extended fall season signified by delays in the freezing of rivers and an extended growing season for grassland vegetation. The study results showed that agricultural practices in the study area are still traditional; that is, local farmers’ perceptions of climate change and their strategies to mitigate its impacts were based on indigenous knowledge and their own experiences. Adaptive strategies included adjusting planting and harvesting dates, changing crop species, and improving irrigation infrastructure. However, the farmers’ decisions could not be fully attributed to their concerns about climate change. Local farming systems exhibit high adaptability to climate variability. Additionally, off-farm income has reduced the dependence of the farmers on agriculture, and an agricultural subsidy from the Chinese Central Government has mitigated the farmers’ vulnerability. Nevertheless, it remains necessary for local farmers to build a system of adaptive climate change strategies that combines traditional experience and indigenous knowledge with scientific research and government polices as key factors. 相似文献
829.
Ford CI Walter M Northcott GL Di HJ Cameron KC Trower T 《Journal of environmental quality》2007,36(6):1599-1608
This study was conducted to improve the pentachlorophenol (PCP) bioremediation ability of white-rot fungi in highly contaminated field soils by manipulating bioaugmentation variables. These were the dry weight percentage of fungal inoculum addition (31-175 g kg(-1)), PCP concentration (100-2137 mg kg(-1) PCP), fungal inoculum formulation, and time (1-7 wk). Five fungal isolates were used: the New Zealand isolates Trametes versicolor (L.: Fr.) HR131 and Trametes sp. HR577; the North American isolates Phanerochaete chrysosporium Burds. (two isolates) and Phanerochaete sordida (Karst.) Erikss. & Ryv. Pentachlorophenol removal, manganese peroxidase, and laccase activity, and the formation of chloroanisoles in the contaminated field soils were measured. The majority of PCP removed by the Trametes isolates was in the first week after bioaugmentation. The maximum PCP removal by the fungi varied from 50 to 65% from a 1065 mg kg(-1) PCP contaminated field soil. Pentachlorophenol was preferentially converted to pentachloroanisole (PCA) by the Phanerochaete isolates (>60%), while 2 to 9% of the PCP removed by two Trametes isolates was converted to PCA. A pH increase was measured following bioaugmentation that was dependent on PCP concentration, fungal inoculum addition, and formulation. This, together with rapid initial PCP removal, possibly changed the bioavailability of the remaining PCP to the fungi and significantly decreased the sequestering of PCP in the contaminated field soils. The research supports the conclusion that New Zealand Trametes spp. can rapidly remove PCP in contaminated field soils. Bioavailability and extractability of PCP in the contaminated field soil may significantly increase after bioaugmentation. 相似文献
830.
Phosphate rock (PR) and phosphoric acid (PA) are an effective combination of P sources for immobilizing Pb in contaminated soils. This column experiment examined the effectiveness of different application methods on Pb immobilization in a contaminated soil. Phosphate was applied at a P/Pb molar ratio of 4 with half as PR and half PA. While PR was mixed with the soil or placed as a layer, aqueous PA was applied from the top of the column as one or two applications. After 4 wk of incubation, total and soluble Pb and P, TCLP-Pb (toxicity characteristic leaching procedure) and PBET-Pb (physiologically-based extraction test) in the P-treated soil were determined. Phosphate addition effectively reduced leachable Pb to below the EPA drinking water standard of 15 microg L(-1) in all treatments. Mixing both PA and PR with the soil was the most effective method in Pb immobilization, reducing TCLP-Pb by up to 95% and PBET-Pb by 25 to 42%. Application of PR as a layer in the soil column was the most effective in reducing Pb migration (by 73-79%) and minimizing soil acidification and P entrophication, potential drawbacks of PA. Applying PA in two applications was less effective than one application. Mixing PR and PA with the soil plus placing PR as a layer can be employed for effective remediation of Pb-contaminated soils, reducing Pb leachability, bioavailability, and mobility while minimizing soil acidification and P entrophication. 相似文献