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991.
This study involves a meta-analytical review of several articles, using the closest assumptions for the independent variable (renewable energy consumption), to determine the relationship with its environmental impacts. Furthermore, Sustainable Development Goal (SDG) in 2015 pays attention to related problems in both developing and developed countries. The effects of carbon emissions, natural resources, renewable energy consumption, and non-renewable energy on the environment are also reviewed. Following the separation of studies, the closest assumption was observed for the independent variable (energy source applications) of renewable energy. The meta-analysis was obtained using OpenMEE and JASP, and the results show the observed outcome, which was expressed in percentage. Based on the analysis, the Renewable Energy model has a value of 0.15, with the largest forest plots of 0.73, 0.69, and 0.80, recorded for studies 13, 19, and 23, respectively, while the least forest plots were recorded for studies 6, 11, 12, 15, 20, 22, 24, 25, 26, and 28. Therefore, renewable energy consumption, specifically in the mining industry, has the capacity to influence global warming. The respective industry has a unique influence on the processes that require renewable energy, for instance, the coal mining industry produces a smaller forest plot value, compared to oil and gas, or other mineral industries.  相似文献   
992.
Forest die‐off around the world is expected to increase in coming decades as temperature increases due to climate change. Forest die‐off will likely affect understory plant communities, which have substantial influence on regional biological diversity, ecosystem function, and land–atmosphere interactions, but how die‐off alters these plant communities is largely unknown. We examined changes in understory plant communities following a widespread, drought‐induced die‐off of trembling aspen (Populus tremuloides) in the western United States. We assessed shrub and herbaceous cover and volume in quadrats in 55 plots located across a wide range of levels of aspen mortality. We measured species richness and composition of herbaceous plant communities by recording species presence and absence in 12 sets of paired (1 healthy, 1 dying) aspen plots. Although understory composition in healthy and dying stands was heterogeneous across the landscape, shrub abundance, cover, and volume were higher and abundance of herbaceous species, cover, and volume were lower in dying aspen stands. Shrub cover and volume increased from 2009 to 2011 in dying stands, which suggests that shrub growth and expansion is ongoing. Species richness of herbs declined by 23% in dying stands. Composition of herbs differed significantly between dying and healthy stands. Richness of non‐native species did not differ between stand types. The understory community in dying aspen stands was not similar to other shrub‐dominated plant communities in the region and may constitute a novel community. Our results suggest that changes in understory plant communities as forests die off could be a significant indirect effect of climate change on biological diversity and forest communities. Efectos de la Mortalidad Extensiva de Álamos Inducida por Sequía sobre Plantas del Sotobosque  相似文献   
993.
High costs of land in agricultural regions warrant spatial prioritization approaches to conservation that explicitly consider land prices to produce protected‐area networks that accomplish targets efficiently. However, land‐use changes in such regions and delays between plan design and implementation may render optimized plans obsolete before implementation occurs. To measure the shelf life of cost‐efficient conservation plans, we simulated a land‐acquisition and restoration initiative aimed at conserving species at risk in Canada's farmlands. We accounted for observed changes in land‐acquisition costs and in agricultural intensity based on censuses of agriculture taken from 1986 to 2011. For each year of data, we mapped costs and areas of conservation priority designated using Marxan. We compared plans to test for changes through time in the arrangement of high‐priority sites and in the total cost of each plan. For acquisition costs, we measured the savings from accounting for prices during site selection. Land‐acquisition costs and land‐use intensity generally rose over time independent of inflation (24–78%), although rates of change were heterogeneous through space and decreased in some areas. Accounting for spatial variation in land price lowered the cost of conservation plans by 1.73–13.9%, decreased the range of costs by 19–82%, and created unique solutions from which to choose. Despite the rise in plan costs over time, the high conservation priority of particular areas remained consistent. Delaying conservation in these critical areas may compromise what optimized conservation plans can achieve. In the case of Canadian farmland, rapid conservation action is cost‐effective, even with moderate levels of uncertainty in how to implement restoration goals.  相似文献   
994.
This paper draws on the example of Tyumen Province, a federal subject of the Russian Federation, to explore the role that policies play in hindering agricultural producers’ adaptation to climate change. Its objective is to contribute to a better understanding of maladaptation at the policy level. The discourse analysis method is used to explain perceptions of climate variability in Tyumen Province and its impact on agriculture. The document analysis method is used to assess agricultural policy in Tyumen Province and its implications for producers’ adaptation to climate change. The results suggest that although agricultural producers and policymakers are acutely aware both of climate variability and the resulting loss of agricultural output, provincial agricultural policy generally fails to encourage better adaptation by agricultural producers or to support their greater economic security. Instead, it primarily focuses on meeting food production targets and thus limits the producers’ own independent moves towards adaptation. The phenomenon of maladaptation at the policy level is discussed in consideration of the general public’s and the authorities’ awareness of climate change and climate variability, and the role of science in shaping this awareness.  相似文献   
995.
I studied reproductive costs in the female Columbian ground squirrel (Spermophilus columbianus) using individually marked animals. I compared weight changes during the active season and over winter, and mortality for females that did and did not wean young. Females raising young were heavier at emergence in that spring than unsuccessful ones. Females that did not raise young gained more weight during summer, were heavier than successful females at the time of entry into hibernation, and were heavier emerging from hibernation the following spring. Over-winter mortality was higher for females that reared young compared to reproductively unsuccessful females. A food supplementation experiment showed that energy-rich food can accelerate individuals’ weight gain. Interactions between litter size, birth weight, weight at emergence from the natal burrow, survival of young to yearling age, and maternal fitness were also studied. Litter sizes were experimentally manipulated to evaluate how females cope with costs of rearing one additional young. Birth weight of juveniles was positively correlated with survival to emergence from the natal burrow and with survival to yearling age. Partial litter loss was higher in experimentally enlarged litters than in either experimentally decreased or control litters. Total litter loss, survival of adult females or the probability of weaning young the following year were not affected by the litter size manipulation. Females appear to adjust the size of their litter before birth, and to some extent during lactation, to their ability to wean young. Received: 20 January 2000 / Received in revised form: 12 March 2000 / Accepted: 18 March 2000  相似文献   
996.
随着机械、电子器件可靠性的不断提高,系统的安全性越来越取决于人的行为。当人处于不良的精神状态,就可能做出本人意愿之外的失误,从而导致事故的发生。因此,针对人的无意识失误进行分析并提出改进措施,可以提高系统的安全水平,降低事故风险。本文提出的精神熵分析方法,以安全学原理、心理学、安全人机工程学为基础提出六个评价指标,结合熵权法的计算原理。通过班组人员岗前自评的形式,员工给出六项指标的分数,并计算自己的最终得分,以此来评估员工在岗时的精神状态。管理者依据一定原则对低分项进行询问,发现问题并提出解决办法,最终降低并控制无意识失误导致的事故风险。  相似文献   
997.
Abstract:  Priorities for conservation, management, and associated activities will differ based on the interplay between nearness of ecosystems to full recovery from a disturbance (pristineness), susceptibility to climate change (environmental susceptibility [ES]), and capacity of human communities to cope with and adapt to change (social adaptive capacity [AC]). We studied 24 human communities and adjacent coral reef ecosystems in 5 countries of the southwestern Indian Ocean. We used ecological measures of abundance and diversity of fishes and corals, estimated reef pristineness, and conducted socioeconomic household surveys to determine the AC of communities adjacent to selected coral reefs. We also used Web-based oceanographic and coral mortality data to predict each site's ES to climate warming. Coral reefs of Mauritius and eastern Madagascar had low ES and consequently were not predicted to be affected strongly by warm water, although these sites were differentiated by the AC of the human community. The higher AC in Mauritius may increase the chances for successful self-initiated recovery and protective management of reefs of this island. In contrast, Madagascar may require donor support to build AC as a prerequisite to preservation efforts. The Seychelles and Kenya had high ES, but their levels of AC and disturbance differed. The high AC in the Seychelles could be used to develop alternatives to dependence on coral reef resources and reduce the effects of climate change. Pristineness weighted toward measures of fish recovery was greatest for Kenya's marine protected areas; however, most protected areas in the region were far from pristine. Conservation priorities and actions with realistic chances for success require knowledge of where socioecological systems lie among the 3 axes of environment, ecology, and society.  相似文献   
998.
The social and economic ramifications of marine conservation strategies such as marine protected areas (MPAs) are important to consider prior to their implementation to ensure that they do not exceed the resilience of resource-users and that resource protection might be maximised through compliance and low resistance. This paper presents a framework in which the human dimensions can be more easily and usefully integrated into the design and delivery of conservation initiatives. The framework espouses quantifying (1) the level of dependency on the resource; (2) perceptions towards conservation initiatives; and (3) social resilience. The framework is applied in Salum, Egypt, which is the site of a prospective MPA.  相似文献   
999.
An assessment of the impact of sea level rise on the city of Port Said, Egypt has been carried out using remote sensing and GIS techniques. Bruun's is used to estimate horizontal retreat, due to three scenarios of sea level rise, taking into account local subsidence rates. Overlaying horizontal retreat on land use obtained by remote sensing enabled us to estimate possible losses and socio-economic impacts. Results indicate serious physical and socio-economic impacts. It is suggested that protection measures must be carried out with emphasis on building breakwaters along the most vulnerable shoreline area.  相似文献   
1000.
Factors influencing support for climate mitigation policy in the United States are well researched, however, research regarding individuals’ support for climate adaptation policy is relatively sparse. This study explores how an individual’s perception of climate change impacts may influence their support for adaptation actions. Results of a survey of the U.S. public (n = 653) indicates that individuals who believe climate change impacts are unlikely to happen or will primarily affect other people in other places are less likely to be concerned about climate change impacts and less likely to support climate adaptation. However, an individual’s support for climate change adaptation measures is not influenced by their perception of when climate change impacts will occur even when taking into account concern for climate impacts. Critical for policy-makers, a belief that climate adaptation measures will not be effective attenuates the relationship between psychological distance, concern for climate change impacts, and adaptation policy measures. Our results indicate that to effectively communicate about climate change, policy-makers should emphasize that: (i) climate change impacts are occurring, (ii) that their constituents are being affected now, or will be in the future, and (iii) communicate that adaptation measures can be effective in addressing risks associated with climate change impacts.  相似文献   
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