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881.
A Social Analysis of the Bioinvasions of Dreissena polymorpha in Spain and Hydrilla verticillata in Guatemala 总被引:1,自引:0,他引:1
Human agency plays a key role in the processes of biological invasions. This comprises not only the human role in the configuration of driving forces or in the perception of the impacts, but also the conceptualization of alien species themselves as an environmental problem. This paper examines different stakeholders' positions in bioinvasion processes at different scales, and it looks at their relevance for the management of invasive species. It compares two cases: the invasion process of Dreissena polymorpha in the Ebro River in Spain and the case of Hydrilla verticillata in Lake Izabal, Guatemala. Our results are structured according to impacts and to management options. The discussion focuses on the relevance of incorporating the different stakeholders' interests and values in the analysis and management of biological invasions. Although social analysis of stakeholders' positions is necessary in order to foster management actions, it also reveals conflicts on the relevant criteria and on the very definition of invasive species. 相似文献
882.
883.
海伦地区水热耦合特征及其对大豆产量的影响 总被引:1,自引:0,他引:1
农业是受气候变化影响的主要敏感行业之一,气候变暖带来的气温升高以及降水格局的改变对农作物生产有利有弊。论文基于黑龙江海伦地区1978—2004年生长季≥10℃有效积温、降水量和统计年鉴中的大豆产量数据,以积温和降水在季节上的匹配程度作为判断水热耦合的指标,采用气候波动指数、减产风险指数作为大豆产量受气候波动影响程度的指标,研究了在生长季降水量下降和≥10℃有效积温增加的趋势下水热耦合的年际和年内变化特征及其对大豆产量的影响,并分析了偏干旱、正常和湿润年份大豆产量受气候波动影响的特征和减产风险性。结果表明,大豆气候波动指数和产量减产风险指数从大到小均依次为偏干旱年、偏湿润年和正常年,说明海伦地区受气候暖干化影响较大。 相似文献
884.
浙江省县级单元建成区用地绩效评价及其地域差异研究 总被引:4,自引:1,他引:4
为评价浙江省县级单元建成区用地的绩效,并探讨其地域差异,论文采用AHP法、空间分析法,得到研究结果为:构建了基于经济、效益、效率和公平四个维度的土地绩效评价框架;经济绩效与效率绩效呈现较强的空间集聚特征;效益绩效与公平绩效的空间分布趋于离散;综合绩效呈现四种不同的空间模式;用地协调度并不与经济发展水平直接相关。由此得出结论:由于城市的规模报酬递增和工业化水平提高,子绩效中经济绩效与效率绩效呈现较强的空间集聚特征;而效益绩效与公平绩效则体现出相反的两极分化特征;在区域中心城市的产业梯度转移、辐射效应、周边地区的功能承接等机制影响下,H-H绩效和L-L绩效呈显著的空间集聚形态;产业结构升级提高了土地利用协调性,而欠发达地区的土地利用低水平自组织优化机制也可能具有较高的协调度。 相似文献
885.
《Process Safety and Environmental Protection》2014,92(6):862-868
The industrial processes used for the production of nitrogenous fertilizers are the main generators of reactive nitrogen compounds, chemicals and effluents that ultimately impact the biosphere. Exergy analysis has been performed to a nitrogen fertilizer factory in the State of Bahia, Brazil, where the Anaerobic Ammonium Oxidation (Anammox) and other physical–chemical processes are used to partially or totally handle the feed streams normally sent to a stripping tower.The results showed that the combined use of physical–chemical and biological process can improve the overall exergetic efficiency and avoid the emission of reactive compounds to the atmosphere allowing the recovery of the condensate lost as effluent, so that it can be reincorporated in the production of steam network, increasing energy efficiency and environmental performance of the process. 相似文献
886.
公交车作为最常用的交通工具之一,其空间密闭、人员密度大,一旦发生火灾,极易造成群死群伤事故,社会影响恶劣.首先采用鱼刺图分析法(FBF)分析公交车火灾事故发生的原因;再采用事故树分析法(FTA),得出公交车安全门对公交车内人员安全疏散的重要性;在此基础上,以大容量公交车为研究对象,针对不同开门情况设置4个疏散场景,并运用Building Exodus对车内人员疏散情况进行模拟,提出相应建议.结果表明,公交车右侧前门为1.1m、后门为1.Sm,右侧前、后门均为1.Sm,前门、左右两侧后门均为1.5m3种情况下均较原始设计(右侧前、后门均为1.1m)不同程度缩短了人员疏散时间. 相似文献
887.
Introduction: This study performed a path analysis to uncover the behavioral pathways (from contributing factors, pre-crash actions to injury severities) in bicycle-motor vehicle crashes. Method: The analysis investigated more than 7,000 bicycle-motor vehicle crashes in North Carolina between 2007 and 2014. Pre-crash actions discussed in this study are actions of cyclists and motorists prior to the event of a crash, including “bicyclist failed to yield,” “motorist failed to yield,” “bicyclist overtaking motorist,” and “motorist overtaking bicyclist.” Results: Model results show significant correlates of pre-crash actions and bicyclist injury severity. For example, young bicyclists (18 years old or younger) are 23.5% more likely to fail to yield to motor traffic prior to the event of a crash than elder bicyclists. The “bicyclist failed to yield” action is associated with increased bicyclist injury severity than other actions, as this behavior is associated with an increase of 5.88 percentage points in probability of a bicyclist being at least evidently injured. The path analysis can highlight contributing factors related to risky pre-crash actions that lead to severe injuries. For example, bicyclists traveling on regular vehicle travel lanes are found to be more likely to involve the “bicyclist failed to yield” action, which resulted in a total 44.38% (7.04% direct effect + 37.34% indirect effect) higher likelihood of evident or severe injuries. The path analysis can also identify factors (e.g., intersection) that are not directly but indirectly correlated with injury severity through pre-crash actions. Practical Applications: This study offers a methodological framework to quantify the behavioral pathways in bicycle-motor vehicle crashes. The findings are useful for cycling safety improvements from the perspective of bicyclist behavior, such as the educational program for cyclists. 相似文献
888.
为了解某地区铁路职工的身体健康状况,以便有针对性地采取干预措施,保障铁路职工身体健康,于2019年5月至7月对该地区铁路职工3 106人进行健康体检.结果 显示,3 106名职工中发现异常者1 507人,异常检出率为48.52%,其中心血管系统异常率为22.28%、肝功能异常率为20.99%、泌尿系统异常率为5.25%... 相似文献
889.
指出了近几年全国安全生产的严峻形势与安监队伍力量削弱有关,分析了造成企业安监人员流失的原因,提出了稳定安监队伍的措施和建议. 相似文献
890.
Agnieszka Ćwirlej-Sozańska Anna Wilmowska-Pietruszyńska Bernard Sozański 《International journal of occupational safety and ergonomics》2018,24(3):386-394
Purpose. To assess the reliability and validity of the Polish version of the 36-point World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population. Method. One thousand randomly selected individuals, aged 60–70 years, living in south-eastern Poland were assessed using the Polish version of the WHODAS 2.0. Results. The analysis confirmed the high reliability and validity of the tool. Cronbach’s α index was 0.89. The tool had high stability, and the correlation between test and retest results was high. The relevance of the domain selection was high or very high. A factor analysis confirmed the relevance of assigning questions to domains. High theoretical relevance was also demonstrated. Statistically significant differences between those who were and were not suffering from health problems were observed. An analysis of the internal structure of the WHODAS 2.0 revealed strong correlations between the components of each domain and the final result. Conclusion. The Polish version of the WHODAS 2.0 showed high reliability and validity; thus, it can be used to assess health, functioning and disability in the elderly population of Poland. 相似文献