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891.
892.
Regional Environmental Change - Over the past decade, climate change adaptation has become an integral item on the climate policy agendas of several European countries. As such, researchers have... 相似文献
893.
The United Nations Strategic Plan for Biodiversity 2011–2020 is a key initiative within global efforts to halt and eventually reverse the loss of biodiversity. The very first target of this plan states that “by 2020, at the latest, people are aware of the values of biodiversity and the steps they can take to conserve and use it sustainably.” Zoos and aquariums worldwide, attracting more than 700 million visits every year, could potentially make a positive contribution to this target. However, a global evaluation of the educational impacts of visits to zoos and aquariums is entirely lacking in the existing literature. To address this gap, we conducted a large‐scale impact evaluation study. We used a pre‐ and postvisit repeated‐measures survey design to evaluate biodiversity literacy—understanding of biodiversity and knowledge of actions to help protect it—of zoo and aquarium visitors worldwide. Ours was the largest and most international study of zoo and aquarium visitors ever conducted. In total, 5661 visitors to 26 zoos and aquariums from 19 countries around the globe participated in the study. Aggregate biodiversity understanding and knowledge of actions to help protect biodiversity both significantly increased over the course of zoo and aquarium visits. There was an increase from previsit (69.8%) to postvisit (75.1%) in respondents demonstrating at least some positive evidence of biodiversity understanding. Similarly, there was an increase from previsit (50.5%) to postvisit (58.8%) in respondents who could identify actions to help protect biodiversity that could be achieved at an individual level. Our results are the most compelling evidence to date that zoo and aquarium visits contribute to increasing the number of people who understand biodiversity and know actions they can take to help protect biodiversity. Evaluación de la Contribución de los Acuarios y Zoológicos al Objetivo 1 de Biodiversidad de Aichi 相似文献
894.
Environmental Management - China’s urban explosion has resulted in a substantial loss of agricultural production on the fringes of many cities. Farmland is not only converted into urban uses... 相似文献
895.
Gloria R. Leon Gro Mjeldheim Sandal Eric Larsen 《Journal of environmental psychology》2011,31(4):353-360
An overview of the physical, psychological, social, and coping aspects of living and working in polar regions is presented, assessing findings from both expedition teams and work groups. A personal narrative describing the experiences of a polar expeditioner is interspersed in relevant sections to provide a deeper understanding of the challenges of performing in an extreme environment. The application of findings from polar environments as an analog for space missions is discussed. We conclude that further research is needed on the integration of psychosocial and neurobehavioral adaptation. Furthermore, it is important to consider both the positive as well as negative features of living and working in polar and other extreme environments, and develop training strategies and countermeasure tools to optimize performance in these conditions. 相似文献
896.
Landscape--wildfire interactions in southern Europe: implications for landscape management 总被引:5,自引:0,他引:5
Moreira F Viedma O Arianoutsou M Curt T Koutsias N Rigolot E Barbati A Corona P Vaz P Xanthopoulos G Mouillot F Bilgili E 《Journal of environmental management》2011,92(10):2389-2402
Every year approximately half a million hectares of land are burned by wildfires in southern Europe, causing large ecological and socio-economic impacts. Climate and land use changes in the last decades have increased fire risk and danger. In this paper we review the available scientific knowledge on the relationships between landscape and wildfires in the Mediterranean region, with a focus on its application for defining landscape management guidelines and policies that could be adopted in order to promote landscapes with lower fire hazard. The main findings are that (1) socio-economic drivers have favoured land cover changes contributing to increasing fire hazard in the last decades, (2) large wildfires are becoming more frequent, (3) increased fire frequency is promoting homogeneous landscapes covered by fire-prone shrublands; (4) landscape planning to reduce fuel loads may be successful only if fire weather conditions are not extreme. The challenges to address these problems and the policy and landscape management responses that should be adopted are discussed, along with major knowledge gaps. 相似文献
897.
Akshay A. Gowardhan Eric R. Pardyjak Inanc Senocak Michael J. Brown 《Environmental Fluid Mechanics》2011,11(5):439-464
In many cities, ambient air quality is deteriorating leading to concerns about the health of city inhabitants. In urban areas
with narrow streets surrounded by clusters of tall buildings, called street canyons, air pollution from traffic emissions
and other sources may accumulate resulting in high pollutant concentrations. For various situations, including the evacuation
of populated areas in the event of an accidental or deliberate release of chemical, biological and radiological agents, it
is important that models should be developed that produce urban flow fields quickly. Various computational techniques have
been used to calculate these flow fields, but these techniques are often computationally intensive. Most fast response models
currently in use are at a disadvantage in these cases as they are unable to correlate highly heterogeneous urban structures
with the diagnostic parameterizations on which they are based. In this paper, a novel variant of the popular projection method
for solving the Navier–Stokes equations has been developed and applied to produce fast and reasonably accurate parallel computational fluid dynamics (CFD) solutions for flow in complex urban areas. This model, called QUIC-CFD represents an intermediate
balance between fast (on the order of minutes for a several block problem) and reasonably accurate solutions. This paper details
the solution procedure and validates this model for various simple and complex urban geometries. 相似文献
898.
Long-term monitoring programs emphasize power analysis as a tool to determine the sampling effort necessary to effectively document ecologically significant changes in ecosystems. Programs that monitor entire multispecies assemblages require a method for determining the power of multivariate statistical models to detect trend. We provide a method to simulate presence-absence species assemblage data that are consistent with increasing or decreasing directional change in species composition within multiple sites. This step is the foundation for using Monte Carlo methods to approximate the power of any multivariate method for detecting temporal trends. We focus on comparing the power of the Mantel test, permutational multivariate analysis of variance, and constrained analysis of principal coordinates. We find that the power of the various methods we investigate is sensitive to the number of species in the community, univariate species patterns, and the number of sites sampled over time. For increasing directional change scenarios, constrained analysis of principal coordinates was as or more powerful than permutational multivariate analysis of variance, the Mantel test was the least powerful. However, in our investigation of decreasing directional change, the Mantel test was typically as or more powerful than the other models. 相似文献
899.
Changes in climate and land use can impact natural systems across all levels of ecological organization. Most documented and anticipated effects consider species' properties, including phenologies, geographic distributions, and abundances. Responses of higher-level aggregate community or ecosystem properties have not been considered as they are assumed to be relatively stable due to compensatory dynamics and diversity-stability relationships. However, this assumption may not be as fundamental as previously thought. Here we assess stability in the aggregate properties of total abundance, biomass, and energy consumption for small-mammal communities in the Great Basin, using paired historical and modern survey data spanning nearly a century of environmental change. Results show marked declines in each aggregate property independent of spatial scale, elevation, or habitat type, and a reallocation of available biomass and energy favoring diet and habitat generalists. Because aggregate properties directly reflect resource availability, our findings indicate a regionwide decline in resources of 50% over the past century, which may signal a resource crisis. This work illustrates the power of using aggregate properties as indicators of ecological conditions and environmental change at broad spatial and temporal scales. 相似文献
900.