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831.
832.
Monitoring is critical to assess management effectiveness, but broadscale systematic assessments of monitoring to evaluate and improve recovery efforts are lacking. We compiled 1808 time series from 71 threatened and near-threatened terrestrial and volant mammal species and subspecies in Australia (48% of all threatened mammal taxa) to compare relative trends of populations subject to different management strategies. We adapted the Living Planet Index to develop the Threatened Species Index for Australian Mammals and track aggregate trends for all sampled threatened mammal populations and for small (<35 g), medium (35–5500 g), and large mammals (>5500 g) from 2000 to 2017. Unmanaged populations (42 taxa) declined by 63% on average; unmanaged small mammals exhibited the greatest declines (96%). Populations of 17 taxa in havens (islands and fenced areas that excluded or eliminated introduced red foxes [Vulpes vulpes] and domestic cats [Felis catus]) increased by 680%. Outside havens, populations undergoing sustained predator baiting initially declined by 75% but subsequently increased to 47% of their abundance in 2000. At sites where predators were not excluded or baited but other actions (e.g., fire management, introduced herbivore control) occurred, populations of small and medium mammals declined faster, but large mammals declined more slowly, than unmanaged populations. Only 13% of taxa had data for both unmanaged and managed populations; index comparisons for this subset showed that taxa with populations increasing inside havens declined outside havens but taxa with populations subject to predator baiting outside havens declined more slowly than populations with no management and then increased, whereas unmanaged populations continued to decline. More comprehensive and improved monitoring (particularly encompassing poorly represented management actions and taxonomic groups like bats and small mammals) is required to understand whether and where management has worked. Improved implementation of management for threats other than predation is critical to recover Australia's threatened mammals.  相似文献   
833.
Increased temperature and decreased hardness values of the tube metal and development of oxide scale on the inner surface of boiler tubes over prolonged period of time are typical problems in power plants. Appropriate life assessments or condition monitoring of boiler tube should be carried out from time to time. Computer simulations may economically support the post-failure assessment method, i.e. visual inspections, metallurgical examinations and mechanical strength measurements. However, estimations obtained from the simulations may provide an advanced warning to take preventive actions prior to failure. In this work two failure cases of the reheater and superheater tubes made of a typical material of SA213-T22 steel are evaluated. As the oxide scales are increasingly developed on the inner surface, the increasing of temperature and decreasing of hardness value in tube metal for both cases are determined. The remnant life estimations are then made in the form of creep cumulative damages.  相似文献   
834.
Functional Ecosystems and Biodiversity Buzzwords   总被引:1,自引:0,他引:1  
Abstract: Several increasingly popular paradigms in conservation remove organismal information and life-history requirements from management planning with claims that species-specific information is not necessary to the understanding and management of "ecosystem function" and may therefore be discarded. Although several authors have called attention to the fact that ecosystem management has not yet been articulated sufficiently to comprise an adequate paradigm for wildlife protection, there has been a series of suggestions paralleling ecosystem management's popularity that the perceived or imagined emergent properties of communities should be at the root of conservation planning. Such reductions most commonly take the form of abstracted species diversity measures that may be irrelevant or misleading with respect to site-specific planning and to the monitoring of specific management treatments. Following earlier examinations of ecosystem management, I emphasize that several of its apparent outgrowths may be too vague to inform specific recommendations, that the historical mechanics of "ecosystem processes" are essentially unknowable, and that anecdotal definitions of ecosystems allow one to justify virtually any protocol as management. The primacy of process-dependent, landscape-functional considerations in conservation planning is specious in the absence of species- and population-specific information, which should form the foundation for understanding such processes in the first place. Only by viewing nature in terms of the relationships between processes and organisms, rather than in terms of emergent properties of organismal assemblages or abiotic factors divorced from organismal data, can conservation plans claim to protect biological elements.  相似文献   
835.
Productivity in Conservation Research in the Southern Hemisphere   总被引:2,自引:0,他引:2  
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836.
Environmental Science and Pollution Research - Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important...  相似文献   
837.
Based on data from a Qualtrics panel, this study examines Chinese citizens’ motivations for information seeking about air pollution. Results from structural equation modelling indicate that information insufficiency, negative affect, attitudes toward seeking, and perceived information gathering capacity are positively related to information seeking. Informational subjective norms, however, were not significantly related to information seeking. Further, participants with more knowledge and higher risk perception were more likely to desire more information about air pollution. These results suggest that communication campaigns should highlight individuals’ personal risks and self-efficacy to encourage greater information seeking about air pollution among Chinese citizens. Emotional appeal may serve as an effective strategy as well.  相似文献   
838.
Russian Journal of Ecology - There are increasing evidences documenting the negative impact of exotic species including mosquitofish, Gambosi affinis, in Iran. Meanwhile, recent climate change in...  相似文献   
839.
Environmental Science and Pollution Research - The Moravian-Silesian region of the Czech Republic with its capital city Ostrava is a European air pollution hot spot for airborne particulate matter...  相似文献   
840.
Acid mine drainage from mine tailings at Selebi Phikwe, eastern Botswana, has been investigated using a combination of total decomposition, sequential extraction, X-ray diffraction, Mössbauer spectroscopy, and SEM analyses of solid phase samples, water analyses, isotopic analyses, and geochemical modeling. The principal ferric phases in the seepage stream sediments are jarosite and goethite, which incorporate Ni and Cu. The Mössbauer spectroscopy (MS) indicated exclusively 3+ oxidation state of iron with typical features of ferric hydroxides/sulfates. A fraction of dissolved sulfate is also sequestered in gypsum which precipitates further downstream. Significant portions of Fe, Ni, and Cu are transported in suspension. Values of pH decreased downstream due to H+ generated by the precipitation of jarosite. Values of δ2H and δ18O indicate evaporation of pore water in the mine tailings before seepage. Values of δ34S(SO4) are consistent with the oxidation of sulfides, but sample from the seepage face is affected by dissolution of gypsum. No minerals of Ni and Cu were detected and the principal attenuation processes seem to be adsorption and co-precipitation with jarosite. Higher contents of Cu are sequestered in solid phases compared to Ni, in spite of much higher dissolved Ni concentrations. Based on the speciation calculations, seepage water is undersaturated with respect to all Ni and Cu phases and adsorption and co-precipitation with jarosite seems to be the principal attenuation processes. Direct geochemical modeling was able to reproduce downstream pH trends, thus confirming the precipitation of jarosite as the principal pH-controlling process.  相似文献   
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