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Human activities levy a biological cost on ecosystems as resources are accessed and utilized at rates which are often incompatible with inherent ecosystem processes and structures. The recreational impact of humans upon intertidal zones and particularly fucoid algal assemblages is one major threat facing coastal ecosystems. The effect of human values, knowledge and perception in effecting biologically costly behaviors has rarely been examined. We hypothesize that with respect to intertidal zones: (1) Personal attribution and perception of ecosystem resiliency are more important than knowledge in determining the extent of depreciative behaviors individuals engage in, and; (2) Individuals who are uncertain about ecosystem resiliency will behave in a manner consistent with the 'precautionary principle'. We measured the depreciative behavior, and the attitudes and perceptions to ecosystem resilience, of visitors to Wick Headland in Pacific Rim National Park, British Columbia. Attitudes, knowledge, perceptions, and personal attribution were measured using questionnaire survey and structured interviews undertaken in situ. Depreciative behaviors of visitors were discreetly observed and correlated to the questionnaire survey and interview responses. We show that visitors who recorded greater knowledge of intertidal ecology engaged in more depreciative behaviors than visitors recording less knowledge. Visitors who perceived high ecosystem resilience in the intertidal zone engaged in significantly more behaviors eliciting biological cost than those who perceived low ecosystem resilience. Visitors who recorded uncertainty regarding ecosystem resilience engaged in significantly more depreciative behaviors than those who perceived low ecosystem resilience but slightly fewer depreciative behaviors than those who perceived high ecosystem resilience. Personal attribution was inversely correlated to the mean number of depreciative behaviors. We discuss the relevance of these results to the management of intertidal zones and marine protected areas, to multiple use management, the management of visitor impact, and natural resource use.  相似文献   
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Abstract

Makerspaces – open access design and fabrication workshops – provide new contexts for design practice through ‘distributed production’. The global community of makerspaces has evolved quickly and in turn, substantial hype is attributed to its potential for radical sustainable innovation. In this article, we explore this potential in the context of the new ‘circular economy’ agenda. We focus the research on the critical role of makerspace managers/founders who are recognised as gatekeepers to circular practices. The research method is action-led including expert interviews (academics and founders/managers) as well as two generative context-mapping workshops, run at selected makerspaces in collaboration with their founders/managers. We unearth everyday ‘how-to’ guidance to interweave circular practices within makerspaces from the outset by: fostering an enabling culture; building local connections; nurturing individual/community capacities; and stimulating practical know-how. However, while the research reveals immense opportunities to cultivate circular literacy from within makerspaces, the prospects to ask more profound questions about our economy, through makerspace practices, are found to be compromised by day-to-day concerns. The insights from this research can act as a starting point for future work in this emerging research area.  相似文献   
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The effect of cell preparation methods on the surface chemistry and retention of Escherichia coli D21 g was investigated over a range of ionic strength conditions. The cell preparation methods that were considered included filtration and centrifugation (at various speeds and for different durations). For a given ionic strength condition, it was found that cells prepared by filtration were more negatively charged and hydrophobic than cells prepared by centrifugation. Increasing the centrifugation speed (force imposed) or duration produced cells with a higher zeta potential (less negative) and a lower hydrophobicity. Column transport experiments for E. coli D21 g were also conducted with ultra pure quartz sand and the same solution chemistries. The first-order retention rate coefficient for E. coli D21 g increased with increasing speed and duration of centrifugation, and was lowest in the case of filtered cells. Moreover, the influence of cell preparation method was more pronounced in lower ionic strength solutions.  相似文献   
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