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121.
For land-use science to engage the general public it must successfully translate its concepts and conclusions and make them public outside of traditional scientific venues. Here we explore science-art exhibits, which blend artistic presentations with specific scientific data or themes, as a possible effective way of communicating scientific information and disrupting misconceptions. We describe the process of producing a science-art exhibit on remote sensing and Puerto Rican landscape history from 1937 to the present, sited at a rural Puerto Rican community museum, and examine the visitor experience and educational outcomes of the museum exhibit through analysis of survey data. The exhibit project engaged undergraduate students from a variety of academic backgrounds, introduced land-use science concepts to the public in an engaging format, and was effective at reshaping visitors’ misconceptions of Puerto Rico’s landscape change history.  相似文献   
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A multicommutated flow system was designed and evaluated for the determination of total arsenic and selenium by Hydride Generation Atomic Absorption Spectrometry (HG-AAS). It was applied to the determination of arsenic and selenium in samples of natural and drinking water. Detection limits were 0.46 and 0.08 μg l−1 for arsenic and selenium, respectively; sampling frequency was 120 samples h−1 for arsenic and 160 samples h−1 for selenium. Linear ranges found were 1.54–10 μg l−1 (R = 0.999) for arsenic and 0.27–27 μg l−1 (R = 0.999) for selenium. Accuracy was evaluated by spiking various water samples and using a reference material. Recoveries were in the range 95–116%. Analytical precision (s r (%), n = 10) was 6% for both elements. Compared with the Standard Methods, APHA, 3114B manual method, the system consumes at least 10 times less sample per determination, and the quantities of acid and reducing agent used are significantly lower with a reduction in the generation of pollutants and waste. As an additional advantage, the system is very fast, efficient and environmentally friendly for monitoring total arsenic and selenium levels in waters.  相似文献   
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One major limitation in the use of body feathers of seabirds as a monitoring tool of the trophic structure and contamination levels of marine ecosystems is the degree of heterogeneity in feather chemical composition within individuals. Here, we tested the hypothesis that moulting patterns drive body feather heterogeneity, with synchronous moult minimizing within-individual variations, in contrast to asynchronous feather growth. Chicks of white-chinned petrels Procellaria aequinoctialis (representative of bird chicks) and adults of king penguins Aptenodytes patagonicus (representative of adult penguins) that moult their body feathers synchronously showed very low within-individual variations in their feather δ13C and δ15N values and mercury (Hg) concentrations. By contrast, body feathers of adults of Antarctic prions Pachyptila desolata (representative of adult seabirds with asynchronous feather growth during a protracted moult) presented much higher within-individual variances for the three parameters. These findings have three important implications for birds presenting a synchronous body moult. (1) They suggest that all body feathers from the same individual have identical δ13C and δ15N values and Hg content. (2) They predict negligible within-individual variations in the body feather values of other useful stable isotopes, such as δ2H and δ34S, as well as in the concentrations of other compounds that are deposited in the keratin structure. (3) Analysis of one or any number of pooled body feathers is equally representative of the individual. In conclusion, we recommend that long-term routine monitoring investigations focus on birds presenting synchronous rather than asynchronous moult of body feathers both in marine and terrestrial environments. This means targeting chicks rather than adults and, for seabirds, penguins rather than adults of flying species.  相似文献   
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Environmental Science and Pollution Research - In this work, different analytical techniques (thermal analysis, 13C cross-polarization magic angle spinning (CPMAS) NMR and Fourier transform...  相似文献   
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Methods to assess ecosystem services using ecological or economic approaches are considerably better defined than methods for the social approach. To identify why the social approach remains unclear, we reviewed current trends in the literature. We found two main reasons: (i) the cultural ecosystem services are usually used to represent the whole social approach, and (ii) the economic valuation based on social preferences is typically included in the social approach. Next, we proposed a framework for the social valuation of ecosystem services that provides alternatives to economics methods, enables comparison across studies, and supports decision-making in land planning and management. The framework includes the agreements emerged from the review, such as considering spatial–temporal flows, including stakeholders from all social ranges, and using two complementary methods to value ecosystem services. Finally, we provided practical recommendations learned from the application of the proposed framework in a case study.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0555-2) contains supplementary material, which is available to authorized users.  相似文献   
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Samples of air (gas and particulate phases), bulk deposition, aquatic settling material and sediments were collected in Lake Maggiore (LM) in order to determine their content of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Air (gas and particulate phases) concentrations were 0.5 pg m(-3), 80 pg m(-3), 13 pg m(-3) and 106 pg m(-3) for SigmaPCDD/Fs, SigmaPCBs, Sigma dioxin-like PCBs (DL-PCBs) and SigmaPBDEs, respectively. Deposition fluxes ranged from 0.7 ng m(-2) d(-1) for SigmaPCDD/Fs to 32 ng m(-2) d(-1) for SigmaPCBs. Aquatic settling material presented concentrations of 0.4 ng g(-1) dry weight (dw) for SigmaPCDD/Fs, 13 ng g(-1) dw for SigmaPCB, 3.4 ng g(-1) dw for SigmaDL-PCBs and 5.7 ng g(-1) dw for SigmaPBDEs. Mean sediment concentrations were 0.4 ng g(-1) dw for SigmaPCDD/Fs, 11 ng g(-1) dw for SigmaPCB, 3 ng g(-1) dw for SigmaDL-PCBs and 5.1 ng g(-1) dw for SigmaPBDEs. Similar PCDD/F and DL-PCB congener patterns in all the environmental compartments of LM point to an important, if not dominant, contribution of atmospheric deposition as source of these pollutants into LM. In contrast, PBDE congener distribution was not similar in the different environmental compartments. BDE 47 dominated air and settling material, while BDE 209 was the predominant congener in the bulk atmospheric deposition. Moreover, sediments showed two distinct PBDE congener profiles. Lower PBDE concentrated sediments were dominated by congeners 47 and 99, while BDE 209 dominated in higher PBDE concentrated samples. This suggests the influence of local sources as well as atmospheric input of PBDEs into LM.  相似文献   
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The recognition that growing proportions of species worldwide are endangered has led to the development of comparative analyses to elucidate why some species are more prone to extinction than others. Understanding factors and patterns of species vulnerability might provide an opportunity to develop proactive conservation strategies. Such comparative analyses are of special concern at national scales because this is the scale at which most conservation initiatives take place. We applied powerful ensemble learning models to test for biological correlates of the risk of decline among the Bolivian mammals to understand species vulnerability at a national scale and to predict the population trend for poorly known species. Risk of decline was nonrandomly distributed: higher proportions of large‐sized taxa were under decline, whereas small‐sized taxa were less vulnerable. Body mass, mode of life (i.e., aquatic, terrestrial, volant), geographic range size, litter size, home range, niche specialization, and reproductive potential were strongly associated with species vulnerability. Moreover, we found interacting and nonlinear effects of key traits on the risk of decline of mammals at a national scale. Our model predicted 35 data‐deficient species in decline on the basis of their biological vulnerability, which should receive more attention in order to prevent their decline. Our results highlight the relevance of comparative analysis at relatively narrow geographical scales, reveal previously unknown factors related to species vulnerability, and offer species‐by‐species outcomes that can be used to identify targets for conservation, especially for insufficiently known species. Predección y Definición de Prioridades de Conservación para Mamíferos de Bolivia con Base en Correlaciones Biológicas del Riesgo de Declinación  相似文献   
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