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871.
Managing authorities in Scandinavia arrange public information meetings when members of the public express fear because wolves or brown bears approach human settlements. This study aimed to increase the understanding of the potential effect of information meetings on self-reported fear of wolves and brown bears. In total, 198 participants completed questionnaires before and after the information meetings. Nine follow-up interviews were held 1 year later. The quantitative analyses revealed that participants who found the information credible reported a significant increase in social trust and a decrease in vulnerability and fear. The qualitative analyses pointed to the importance of information content and meta-communication, for example, nonverbal cues. It is proposed that, among participants who find the information credible, information meetings may change the appraisal of wolves and brown bears, and therefore they might prove useful as an intervention to address fear of these animals.  相似文献   
872.
The article presents a systematic review of 152 articles in which the concept of knowledge is applied and that are published in international human geography journals. As the importance of knowledge in society is increasing, especially economic geography has taken up the task of reviewing the concept or role of knowledge in geography. However, there is a need for a more nuanced understanding of knowledge in economic geography, drawing more broadly on human geographical research. The authors analyse how the concept of knowledge is understood and applied in contemporary human geography. Their results demonstrate four knowledge rationales: economic, policy, empowerment, and methodological. Each rationale and their combinations display a particular role and purpose for knowledge, as well as a distinct approach to space. Separately, each rationale provides several insights into a more nuanced understanding of specific aspects of knowledge. When combined, the four rationales offer a holistic overview of the field. The authors conclude that the empowerment rationale offers novel methodological choices towards a more nuanced understanding of knowledge in economic geography.  相似文献   
873.
This research aims to evaluate the geographical knowledge of nine teachers in the region of Valparaiso, Chile. An interpretive case study was conducted with data collected through classroom observations, interviews, and questionnaires, and these data were then analyzed through triangulation. The findings showed that these teachers, who are the most qualified within the region's context, consider geography to be marginal knowledge in the school curriculum, although they also consider it relevant to the education of their pupils. Both elements provided evidence of the fragility of their geographical knowledge, which fell within a spectrum that combines expert knowledge and lay knowledge.  相似文献   
874.
Although previous investigations of the trace elements in snow and ice from the Qinghai-Tibetan Plateau obtained interesting information about pollution from human activities on the plateau, most were based on traditional acidification methods. To emphasize the influence of the different sample-preparation methods on the records of trace elements and rare earth elements, snow samples were collected from glaciers on the Qinghai-Tibetan Plateau in China and prepared using two methods: traditional acidification and total digestion. Concentrations of 18 trace elements (Al, Ti, Fe, Rb, Sr, Ba, V, Cr, Mn, Li, Cu, Co, Mo, Cs, Sb, Pb, Tl, and U), along with 14 rare earth elements (REEs: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), Y, and Th in the snow samples, were measured using inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The results showed that the mass fraction of the trace elements (defined as ratio of concentration in the acid-leachable fraction to that in the digested sample) such as Mo, Ti, Al, Rb, and V, varied from 0.06 to 0.5. The mass fraction of other trace elements varied from about 0.6 to more than 0.9; those of the REEs, Y, and Th varied from 0.34 to 0.75. Lower mass fractions will lead to an overestimated contribution of other sources, especially human activities, and the underestimated fluxes of these trace elements (especially REEs, Y, and Th, as well as dust) if the REEs are used as the proxy for the crust dust. The two sample-preparation methods exhibited different REE normalized distribution patterns, REE ratios, and provenance-tracing results. The REE normalized distribution patterns and proxies in the digested samples are more reliable and integrated than those found in traditional acidification method for dust-provenance tracing.  相似文献   
875.
876.
Relationships among chemical–physical features, total gross suspended organic matter, coverage of the seagrass Ruppia cirrhosa and its associated algal community in eight ponds of a saltworks system of western Sicily (Mediterranean Sea) were investigated in spring and summer 2004. All biological features varied both at different levels of seagrass coverage and between seasons. A low algal diversity (46 taxa, 14.75 ± 1.41 on average) was highlighted; algal coverage and species richness showed to be negatively correlated. Ruppia cirrhosa coverage was negatively correlated with algal coverage, but positively correlated with species richness. Moreover, a significant correlation among R. cirrhosa coverage, the availability of suspended matter in the water column and the chlorophyll a concentration was detected.  相似文献   
877.
Abstract. The amphipod population of the Fusaro coastal lagoon (Tyrrhenian Sea, Italy) was studied on a spatial-temporal scale. During a one-year period, samples were collected on hard and soft bottoms along a transect from the inland to the seaward side of the lagoon. Thirteen species were identified. The dominant taxa included species typical of lagoon environments, such as Corophium insidiosum and Microdeutopus gryllotalpa , and species typical of marine environments yet also inhabiting sheltered or semi-closed areas, such as Corophium acutum, Ericthonius brasiliensis , and Elasmopus rapax.
An inner-outer gradient was not evident, while a seasonal pattern was recognizable. At the community level, clear differences between the two substrata were not evident because of high algal growth and organogenic detritus on the soft bottoms. The importance of hydrodynamic forces in a euhaline lagoon in selecting amphipod communities - characterized by a typical trophic behaviour and way of life – is discussed. Information on the ecology of the collected species and a list of Mediterranean lagoons where they are present are also provided.  相似文献   
878.
879.
The impact of snow cover on seasonal ground frost and freeze-thaw processes is not yet fully understood. The authors therefore examined how snow cover affects seasonal ground frost in a coastal setting in northern Sweden. Air and soil temperatures were recorded in a paired-plot experiment, both with and without snow cover, during the frost season 2012–2013. The frequency, duration, and intensity of the freeze-thaw cycles during the frost season were calculated. The results showed that the freeze-thaw frequency was 57% higher at the soil surface and the intensity 10 °C colder in the spring of 2013, when the ground lacked snow cover. Furthermore, the duration of the seasonal freeze-thaw cycle was 30 days longer on average in cases where there was natural snow accumulation. The correlation between air and ground surface temperatures weakened with increased snow-cover depth. The authors conclude that continued increases in air temperature and decreases in snow in coastal northern Sweden might alter freeze-thaw cycles and thus affect natural and human systems such as geomorphology, ecology, spatial planning, transport, and forestry.  相似文献   
880.
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