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251.
This paper theorizes how and why safety climate can be conceived as both a leading and a lagging indicator of safety events (i.e., accidents, injuries). When safety climate is conceived as a leading indicator, a prospective design is utilized and safety climate data are correlated with accidents/injuries that occur in the future. When safety climate is conceived as a lagging indicator, retrospective designs are used in which safety climate data are correlated with prior accidents/injuries. We examine the research literature to reveal that safety climate has been investigated as both a leading and a lagging indicator, but it is usually only examined as one or the other within a given study and has been examined as a lagging indicator most frequently. Consistent with our theorizing, prospective designs yield stronger relationships than retrospective designs, suggesting that safety climate is a better leading indicator than lagging indicator; however, it is clearly both. Implications for safety climate research and study design are discussed.  相似文献   
252.
In 1997, the U.S. Environmental Protection Agency (EPA) revised its particulate matter standards to include an annual standard for fine particulate matter (PM2.5; 15 microg/m3) and a 24-hr standard (65 microg/m3). The 24-hr standard was lowered to 35 microg/m3 in 2006 in an effort to further reduce overall ambient PM2.5 concentrations. Identifying and quantifying sources of particulate matter affecting a particular location through source apportionment methods is now an important component of the information available to decision makers when evaluating the new standards. This literature compilation summarizes a subset of the source apportionment research and general findings on fine particulate matter in the eastern half of the United States using Positive Matrix Factorization. The results between studies are generally comparable when comparable datasets are used; however, methodologies vary considerably. Commonly identified source categories include: secondary sulfate/coal burning (sometimes over 50% of total mass), secondary organic carbon/mobile sources, crustal sources, biomass burning, nitrate, various industrial processes, and sea salt. The source apportionment tools and methodologies have passed the proof-of-concept stage and are now being used to understand the ambient composition of particulate matter for sites across the United States and the spatial relationship of sources to the receptor. Recommendations are made for further and standardized method development for source apportionment studies, and specific research areas of interest for the eastern United States are proposed.  相似文献   
253.
The Sahel has been the object of intensive international research since the drought of the early 1970s. A considerable part of the research has focused on environmental change in general and land degradation, land cover change and climate change in particular. Rich and diverse insights from many different scientific disciplines about these three domains have been put forward. One intriguing feature is that an agreement on the overall trends of environmental change does not appear to emerge: questions such as whether the Sahel is greening, cropland is encroaching on rangelands, drought persists remain contested in the scientific literature, and arguments are supported by contrasting empirical evidence. The paper explores the generic reasons behind this situation in a systematic manner. We distinguish between divergences in interpretations emerging from (1) conceptualizations, definitions and choice of indicators, (2) biases, for example, related to selection of study sites, methodological choices, measurement accuracy, perceptions among interlocutors, and selection of temporal and spatial scales of analysis. The analysis of the root causes for different interpretations suggests that differences in findings could often be considered as complementary insights rather than mutually exclusive. This will have implications for the ways in which scientific results can be expected to support regional environmental policies and contribute to knowledge production.  相似文献   
254.
Article impact statement: COVID-19 has demonstrated the need to optimize research activity, convey the gravity of loss, and reevaluate merit in conservation science.  相似文献   
255.
Climatic change results in increased occurrence of heat waves, and the thermal stress caused by such phenomena is leading to higher levels of heat-related mortality worldwide. This study is the first to examine the effect of extreme weather on mortality in Cyprus. It investigates the individual effect of meteorological indicators on mortality, as well as the role of particulate air pollution (PM10). A generalized linear model (GLM) with quasi-Poisson regression was implemented. GLM included a temperature function and was adjusted for relative humidity and seasonality. The temperature function was developed under a newly developed framework of distributed lag nonlinear models, which capture nonlinearities and delayed effects of heat simultaneously. GLM was extended to examine the confounding effect of air pollution. All the results on heat effects are presented. High temperatures had a significant effect on mortality with increased mortality rates, independent of humidity and seasonality. Mortality risk increased steeply above a temperature threshold. A direct heat effect was shown, with higher risk on the current and next day of a severe heat event. PM10 was not found to have a confounding effect on the temperature–mortality relationship, since the strength of this relationship remained after the inclusion of PM10 in the model. Differences existed between urban and coastal areas.  相似文献   
256.
This paper investigates index models as a tool to estimate the risk of N and P source strengths and loss at the catchment scale. The index models assist managers in improving the focus of remediation actions that reduce nutrient delivery to waterbodies. N and P source risk factors (e.g. soil nutrient concentrations) and transport risk factors (e.g. distance-to-streams) are used to determine the overall risk of nutrient loss for a case study in the Tuross River catchment of coastal southeast Australia. In the development of the N index model for Tuross, particulate N was considered important based on the observed event water quality data. In contrast to previous N index models, erosion and contributing distance were therefore included in the Tuross River catchment N index. Event-based water quality monitoring, and soil information, or in data-poor catchments conceptual understanding, are essential to represent catchment-scale processes. The techniques have high applicability in other catchments, and are complementary to other modelling techniques such as process-based semi-distributed modelling. Index models generally provide much more detailed spatial resolution than fully- or semi-distributed conceptual modelling approaches. Semi-distributed models can be used to quantify nutrient loads and provide overall direction to set the broad focus of management. Index models can then be used to refine on-the-ground investigations and investment priorities. In this way semi-distributed models can be combined with index models to provide a set of powerful tools to influence management decisions and outcomes.  相似文献   
257.
Mountain pine beetles, Dendroctonus ponderosae (Hopkins) attack and can ultimately kill individuals and groups of pine trees, specifically lodgepole pine (Pinus contorta Dougl. ex. Loud var. latifolia Engl.). In British Columbia, beetle attack has increased from 164 000 ha in 1999 to over 13 million ha in 2008. Mitigation efforts can play a key role in addressing the impact beetle infestations can have on the forested landscape. In this research, the impact of mitigation on a mountain pine beetle infestation is examined within a network of 28 research plots where sanitation harvesting was completed (10 mitigated plots) and not completed (18 unmitigated plots). Three forest stand level modelling scenarios which predict the number of attacked trees, based on current infestation within the plots, were utilized to compare the differences between mitigated and non-mitigated plots. In the first scenario in the non-mitigated plots, 125 trees were infested after 10 years, while in the mitigated plots no trees were infested in the same time period. The second scenario indicates the level of mitigation required to suppress beetle infestations where the proportion of mitigated trees was calculated for each plot by counting the residual attack and the number of mitigated trees. The average mitigation rate over all plots of 43% (range 0–100%) is not sufficient to provide control. In the non-mitigated plots, the average population expansion rate was 5 (range of 0–18) which requires a detection accuracy of 74% to reliably detect infestation. The third scenario estimated the length of time required for ongoing detection, monitoring, and mitigation to bring an infestation under control. If mitigation efforts were maintained at the current rate of 43%, the beetle population would not be adequately controlled. However, when aided by continued detection and monitoring of attacked trees, mitigation rates greater than 50% are sufficient to control infestations, especially with persistent implementation, aided by continued detection and monitoring of infested trees.  相似文献   
258.
We tested regional-scale spatial patterns in soil microbial community composition for agreement with species sorting and dispersal limitation, two alternative mechanisms behind different models of metacommunity organization. Furthermore, we tested whether regional metacommunity organization depends on local habitat type. We sampled from sites across Ohio and West Virginia hosting populations of Lobelia siphilitica, and compared the metacommunity organization of soil microbial communities under L. siphilitica to those in adjacent areas at each site. In the absence of L. siphilitica, bacterial community composition across the region was consistent with species sorting. However, under L. siphilitica, bacterial community composition was consistent with dispersal limitation. Fungal community composition remained largely unexplained, although fungal communities under L. siphilitica were both significantly different in composition and less variable in composition than in adjacent areas. Our results show that communities in different local habitat types (e.g., in the presence or absence of a particular plant) may be structured on a regional scale by different processes, despite being separated by only centimeters at the local scale.  相似文献   
259.
Neighbourhood parks may serve as a coping resource in post-disaster communities, yet little is known about the impact of large-scale disasters on park use. The objective of this study is to explore the impact of Hurricane Katrina (August 2005) on park use by visitors from flooded areas of New Orleans, Louisiana, compared to visitors from non-flooded areas. In 2006 and 2007, following Hurricane Katrina, 201 adults who visited 27 New Orleans parks were interviewed. Visitors from flooded neighbourhoods used their parks less often and were less likely to engage in animal interaction than visitors from non-flooded neighbourhoods. They placed more importance on escape and physically-active motivations than visitors from non-flooded areas. Social reasons were also more important to visitors from flooded areas, but these differences disappeared after adjusting for race. Neighbourhood parks are a community asset that may play a role in the post-disaster recovery process by providing opportunities for escape and physical activity.  相似文献   
260.
Scaled up planning and implementation of nature-based solutions requires better understanding of broad characteristics (typologies) of the current governance and financing landscape, collaborative approaches amidst local complexities, and factors of scalability. An inventory was compiled of water-related ecological infrastructure intervention projects in two river systems in South Africa, incorporating actor, environmental, social, and financial dimensions and benefits. Qualitative participatory analysis revealed eight typologies. Post-hoc classification analysis determined similarities and/or unique characteristics of seven quantitative typologies. Key characterising factors included the complexity/size of financial flows, complexity of partnership/governance arrangements, mandates/goals of actors, type of ecological infrastructure, trade-offs in investment in ecological/built infrastructure, and the model used for social benefits. Identified scalable typologies offer structures suited to increased investment, with other typologies offering specialised local value. A range of ecological infrastructure intervention typologies with differing biophysical and socioeconomic outcomes provide choices for investors with specific goals, and benefits to landscape actors.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01531-z.  相似文献   
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