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341.
Max Hofmann Laetitia M. Navarro Steve Carver Peter H. Verburg Henrique M. Pereira 《Conservation biology》2015,29(4):1017-1027
Farmland abandonment takes place across the world due to socio‐economic and ecological drivers. In Europe agricultural and environmental policies aim to prevent abandonment and halt ecological succession. Ecological rewilding has been recently proposed as an alternative strategy. We developed a framework to assess opportunities for rewilding across different dimensions of wilderness in Europe. We mapped artificial light, human accessibility based on transport infrastructure, proportion of harvested primary productivity (i.e., ecosystem productivity appropriated by humans through agriculture or forestry), and deviation from potential natural vegetation in areas projected to be abandoned by 2040. At the continental level, the levels of artificial light were low and the deviation from potential natural vegetation was high in areas of abandonment. The relative importance of wilderness metrics differed regionally and was strongly connected to local environmental and socio‐economic contexts. Large areas of projected abandonment were often located in or around Natura 2000 sites. Based on these results, we argue that management should be tailored to restore the aspects of wilderness that are lacking in each region. There are many remaining challenges regarding biodiversity in Europe, but megafauna species are already recovering. To further potentiate large‐scale rewilding, Natura 2000 management would need to incorporate rewilding approaches. Our framework can be applied to assessing rewilding opportunities and challenges in other world regions, and our results could guide redirection of subsidies to manage social‐ecological systems. 相似文献
342.
Laboratory studies were conducted to evaluate airborne release of diacetyl from selected mixtures simulating butter flavorings added to foods. The test materials included diacetyl (97% purity); 0.015%, 0.15%, 1.5%, and 3.0% diacetyl in a water/propylene glycol mixture; 1.5% diacetyl in deionized water or soybean oil; and 3% or 6% diacetyl in a commercial steam distillate from milk fermentation known as “butter starter distillate.” Diacetyl was quantified by gas chromatography with flame ionization detection. Expected concentration-dependent emission patterns based on liquid diacetyl content were demonstrated, but were significantly altered by mixture composition. Soybean oil and deionized water more readily released diacetyl when compared with starter distillate, propylene glycol solutions, and pure diacetyl. Measured diacetyl concentrations under static headspace and dynamic flow-chamber conditions were compared to estimated concentrations utilizing Raoult's law with published and fitted activity coefficient corrections for each mixture, indicating that published coefficients often understated the measured concentrations. It is concluded that headspace (static) and small-chamber (dynamic) measurements of airborne diacetyl provide data to assist in validating model-estimated airborne diacetyl concentrations by using mixture-specific activity coefficients. Implications of these empirical data for validating exposure estimates for diacetyl based on near-field/far-field modeling in workplace settings are discussed. 相似文献
343.
Social capital discourse occupies an important place in disaster studies. Scholars have adopted various inflections of social capital to explain how those with greater amounts of this crucial resource are generally more resilient to disasters and experience speedier recovery. Disaster scholars have also discovered that people typically display altruistic tendencies in the wake of disasters and develop novel networks of mutual support, known as ‘communitas’, which is also seen to build resilience and boost recovery. In this paper, we use the work of Pierre Bourdieu to synthesise these literatures, conceptualising communitas as ‘disaster social capital’. We offer a fleshed-out definition of disaster social capital to distinguish it from regular social capital and discuss the barriers to, and the enablers of, its formation. While primarily a conceptual discussion, we believe that it has practical and policy value for disaster scholars and practitioners interested in inclusive disaster risk reduction as well as full and just recoveries. 相似文献
344.
Elke I. Zimmer Thomas G. Preuss Steve Norman Barbara Minten Virginie Ducrot 《Environmental Sciences Europe》2018,30(1):36