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121.
Varela E  Koustouki V  Davos CH  Eleni K 《Disasters》2008,32(2):280-291
One year after the 7 September 1999 earthquake in Athens, Greece, we investigated the psychological consequences among 305 individuals (71 per cent female) residing in the settlements of Ano Liosia Municipality. Adaptability was difficult (63 per cent) due to limited space (50 per cent). Insecurity feelings were predictive of difficult adaptability (chi2= 29.8, p<0.0001) and were common (63 per cent) among married subjects, independent of age (chi2= 5.0, odds ratio (OR): 0.49, 95 per cent confidence interval (CI): 0.26-0.90). Eighty per cent expressed stress feelings, mainly nervousness/tension (60 per cent). Adaptability (chi2= 5.3, OR: 0.5, 95 per cent CI: 0.27-0.9), age (chi2= 6.5, OR: 1.03, 95 per cent CI: 1.01-1.06), and female gender (chi2= 4.7, OR: 0.48, 95 per cent CI: 0.25-0.90) were independent predictors of stress feelings. The majority (55 percent) developed sleep disorders, chiefly insomnia (60 percent). Adaptability problems were the only predictor of sleep disorders (chi2= 6.4, OR: 0.5, 95 per cent CI: 0.33-0.87). Psychiatric medication use increased after the earthquake.  相似文献   
122.
The release of engineered nanomaterials (ENMs) into the biosphere will increase as industries find new and useful ways to utilize these materials. Scientists and engineers are beginning to assess the material properties that determine the fate, transport, and effects of ENMs; however, the potential impacts of released ENMs on organisms, ecosystems, and human health remain largely unknown. This special collection of four review papers and four technical papers identifies many key and emerging knowledge gaps regarding the interactions between nanomaterials and ecosystems. These critical knowledge gaps include the form, route, and mass of nanomaterials entering the environment; the transformations and ultimate fate of nanomaterials in the environment; the transport, distribution, and bioavailability of nanomaterials in environmental media; and the organismal responses to nanomaterial exposure and effects of nanomaterial inputs, on ecological communities and biogeochemical processes at relevant environmental concentrations and forms. This introductory section summarizes the state of knowledge and emerging areas of research needs identified within the special collection. Despite recent progress in understanding the transport, transformations, and fate of ENMs in model environments and organisms, there remains a large need for fundamental information regarding releases, distribution, transformations and persistence, and bioavailability of nanomaterials. Moreover, fate, transport, bioaccumulation, and ecological impacts research is needed using environmentally relevant concentrations and forms of ENMs in real field materials and with a broader range of organisms.  相似文献   
123.
Environmental personalization and elementary school children's self-esteem   总被引:1,自引:0,他引:1  
Prior research indicates that the physical classroom environment has the potential to affect children's behaviors, academic performance, and cognitive development. However, less is understood about the effect on the socio-emotional development of children. This study investigates the potential role of one aspect of the classroom's physical environment, personalization displays, on children's self-esteem. The study employed a classroom intervention in a quasi-experiment to examine the effects of increasing environmental personalization on children's self-esteem. Thirty-eight kindergarteners and first graders in six classrooms of two elementary schools in a rural community of a north-eastern state were assessed on pretests and post-tests of the Self-Esteem Index (SEI) scale and the Children's Inventory of Self-Esteem (CISE) scale. The findings were mixed but encouraging. On both measures of self-esteem, there was a significant positive effect of classroom personalization for first graders. However, for kindergarteners there was a significant positive effect for only one measure, the CISE. Although there are limitations with the study design, the findings suggest that young children's self-esteem may be influenced and enhanced by specific aspects of the classroom's physical environment.  相似文献   
124.
An ozone abatement strategy for the South Coast Air Basin (SoCAB) has been proposed by the South Coast Air Quality Management District (SCAQMD) and the California Air Resources Board (ARB). The proposed emissions reduction strategy is focused on the reduction of nitrogen oxide (NOx) emissions by the year 2030. Two high PM2.5 concentration episodes with high ammonium nitrate compositions occurring during September and November 2008 were simulated with the Community Multi-scale Air Quality model (CMAQ). All simulations were made with same meteorological files provided by the SCAQMD to allow them to be more directly compared with their previous modeling studies. Although there was an overall under-prediction bias, the CMAQ simulations were within an overall normalized mean error of 50%; a range that is considered acceptable performance for PM modeling. A range of simulations of these episodes were made to evaluate sensitivity to NOx and ammonia emissions inputs for the future year 2030. It was found that the current ozone control strategy will reduce daily average PM2.5 concentrations. However, the targeted NOx reductions for ozone were not found to be optimal for reducing PM2.5 concentrations. Ammonia emission reductions reduced PM2.5 and this might be considered as part of a PM2.5 control strategy.

Implications: The SCAQMD and the ARB have proposed an ozone abatement strategy for the SoCAB that focuses on NOx emission reductions. Their strategy will affect both ozone and PM2.5. Two episodes that occurred during September and November 2008 with high PM2.5 concentrations and high ammonium nitrate composition were selected for simulation with different levels of nitrogen oxide and ammonia emissions for the future year 2030. It was found that the ozone control strategy will reduce maximum daily average PM2.5 concentrations but its effect on PM2.5 concentrations is not optimal.  相似文献   

125.
At the global scale, biodiversity indicators are typically used to monitor general trends, but are rarely implemented with specific purpose or linked directly to decision making. Some indicators are better suited to predicting future change, others are more appropriate for evaluating past actions, but this is seldom made explicit. We developed a conceptual model for assigning biodiversity indicators to appropriate functions based on a common approach used in economics. Using the model, indicators can be classified as leading (indicators that change before the subject of interest, informing preventative actions), coincident (indicators that measure the subject of interest), or lagging (indicators that change after the subject of interest has changed and thus can be used to evaluate past actions). We classified indicators based on ecological theory on biodiversity response times and management objectives in 2 case studies: global species extinction and marine ecosystem collapse. For global species extinctions, indicators of abundance (e.g., the Living Planet Index or biodiversity intactness index) were most likely to respond first, as leading indicators that inform preventative action, while extinction indicators were expected to respond slowly, acting as lagging indicators flagging the need for evaluation. For marine ecosystem collapse, indicators of direct responses to fishing were expected to be leading, while those measuring ecosystem collapse could be lagging. Classification defines an active role for indicators within the policy cycle, creates an explicit link to preventative decision-making, and supports preventative action.  相似文献   
126.
Field-based cultivation of Kappaphycus and Eucheuma seaweeds is widespread across the tropics and is largely done to extract the polysaccharide carrageenan, which is used in commercial applications. Although such seaweed farming has been cited as a sustainable alternative livelihood to destructive fishing, there has not been a comprehensive review of its environmental impacts to assess its potential conservation benefit. We reviewed the peer-reviewed and industry gray literature to determine what is known about seaweed farming techniques and their impacts on local ecosystems, organisms, and ecosystem services. We identified 43 tropical or subtropical countries that are currently cultivating or have cultivated carrageenophytes. Ecosystem impacts of seaweed farming were measured directly in 33 publications with variable results. Placement of seaweed farms above seagrass beds led to reduced productivity and shoot density in 5 studies and reduced or altered meiofaunal abundance and diversity in 6 studies. On coral reefs, overgrowth of corals by farmed seaweed species was documented in 8 cases. Two studies showed changes to herbivorous fish communities in adjacent areas because seaweed farms changed the environment, whereas in 2 studies measures of overall abundance or diversity did not change. The impacts of seaweed farming may not be as destructive as some other human activities, but they should still be considered when establishing new farms or managing existing farm sites. Our findings are consistent with suggestions to mitigate impact on local ecosystems by shifting seaweed farms to deeper, sandy-bottom areas. However, some of these changes may adversely affect farmers and associated communities.  相似文献   
127.
Poaching is rapidly extirpating African forest elephants (Loxodonta cyclotis) from most of their historical range, leaving vast areas of elephant‐free tropical forest. Elephants are ecological engineers that create and maintain forest habitat; thus, their loss will have large consequences for the composition and structure of Afrotropical forests. Through a comprehensive literature review, we evaluated the roles of forest elephants in seed dispersal, nutrient recycling, and herbivory and physical damage to predict the cascading ecological effects of their population declines. Loss of seed dispersal by elephants will favor tree species dispersed abiotically and by smaller dispersal agents, and tree species composition will depend on the downstream effects of changes in elephant nutrient cycling and browsing. Loss of trampling and herbivory of seedlings and saplings will result in high tree density with release from browsing pressures. Diminished seed dispersal by elephants and high stem density are likely to reduce the recruitment of large trees and thus increase homogeneity of forest structure and decrease carbon stocks. The loss of ecological services by forest elephants likely means Central African forests will be more like Neotropical forests, from which megafauna were extirpated thousands of years ago. Without intervention, as much as 96% of Central African forests will have modified species composition and structure as elephants are compressed into remaining protected areas. Stopping elephant poaching is an urgent first step to mitigating these effects, but long‐term conservation will require land‐use planning that incorporates elephant habitat into forested landscapes that are being rapidly transformed by industrial agriculture and logging.  相似文献   
128.
129.
Sponges are important for maintaining ecosystem function and integrity of marine and freshwater benthic communities worldwide. Despite this, there has been no assessment of their current global conservation status. We assessed their status, accounting for the distribution of research effort; patterns of temporal variation in sponge populations and assemblages; the number of sponges on threatened species lists; and the impact of environmental pressures. Sponge research effort has been variable; marine sponges in the northeastern Atlantic and Mediterranean and freshwater sponges in Europe and North America have received the most attention. Although sponge abundance has increased in some locations since 1990, these were typically on coral reefs, in response to declines in other benthic organisms, and restricted to a few species. Few data were available on temporal trends in freshwater sponge abundance. Despite over 8500 described sponge species, only 20 are on threatened species lists, and all are marine species from the northeastern Atlantic and Mediterranean. Of the 202 studies identified, the effects of temperature, suspended sediment, substratum loss, and microbial pathogens have been studied the most intensively for marine sponges, although responses appear to be variable. There were 20 studies examining environmental impacts on freshwater sponges, and most of these were on temperature and heavy metal contamination. We found that most sponges do not appear to be threatened globally. However, little information is available for most species and more data are needed on the impacts of anthropogenic‐related pressures. This is a critical information gap in understanding sponge conservation status. Estado Global de la Conservación de Esponjas  相似文献   
130.
Recognizing that protected areas (PAs) are essential for effective biodiversity conservation action, the Convention on Biological Diversity established ambitious PA targets as part of the 2020 Strategic Plan for Biodiversity. Under the strategic goal to “improve the status of biodiversity by safeguarding ecosystems, species, and genetic diversity,” Target 11 aims to put 17% of terrestrial and 10% of marine regions under PA status by 2020. Additionally and crucially, these areas are required to be of particular importance for biodiversity and ecosystem services, effectively and equitably managed, ecologically representative, and well‐connected and to include “other effective area‐based conservation measures” (OECMs). Whereas the area‐based targets are explicit and measurable, the lack of guidance for what constitutes important and representative; effective; and OECMs is affecting how nations are implementing the target. There is a real risk that Target 11 may be achieved in terms of area while failing the overall strategic goal for which it is established because the areas are poorly located, inadequately managed, or based on unjustifiable inclusion of OECMs. We argue that the conservation science community can help establish ecologically sensible PA targets to help prioritize important biodiversity areas and achieve ecological representation; identify clear, comparable performance metrics of ecological effectiveness so progress toward these targets can be assessed; and identify metrics and report on the contribution OECMs make toward the target. By providing ecologically sensible targets and new performance metrics for measuring the effectiveness of both PAs and OECMs, the science community can actively ensure that the achievement of the required area in Target 11 is not simply an end in itself but generates genuine benefits for biodiversity.  相似文献   
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