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941.
Being an archipelagic nation, the Philippines is susceptible and vulnerable to the ill-effects of weather-related hazards. Extreme weather events, which include tropical cyclones, monsoon rains and dry spells, have triggered hazards (such as floods and landslides) that have turned into disasters. Financial resources that were meant for development and social services have had to be diverted in response, addressing the destruction caused by calamities that beset different regions of the country. Changing climatic patterns and weather-related occurrences over the past five years (2004-08) may serve as an indicator of what climate change will mean for the country. Early recognition of this possibility and the implementation of appropriate action and measures, through disaster risk management, are important if loss of life and property is to be minimised, if not totally eradicated. This is a matter of urgent concern given the geographical location and geological characteristics of the Philippines.  相似文献   
942.
通过开顶式温室(Open top chambers,OTCs)升温以及刈割+施加牛粪处理,应用磷脂脂肪酸(Phospholipid fatty acids,PLFAs)方法,研究了青藏高原东部高寒草甸土壤微生物群落结构对气候变暖和放牧的响应.结果表明,高寒草甸在生长季节,微生物群落以细菌为主.平均1.17℃的土壤升温使土壤微生物PLFAs总量增加34.58%,而春季割草结合牛粪施加使微生物PLFAs总量增加65.77%.模拟变暖和放牧均引起土壤微生物群落结构的显著变化.升温使细菌相对含量增加8.80%,而使真菌相对含量降低17.48%,细菌与真菌之比由7.3变为9.6.放牧使细菌相对含量增加8.40%,真菌相对含量降低14.04%,细菌与真菌之比由7.3变为9.2.OTCs升温+放牧处理比单独的升温或放牧处理对土壤微生物总量和细菌与真菌比值的影响更加明显.本研究表明,气候变暖和人类活动能够在短期内显著地改变青藏高原高寒草甸土壤微生物群落结构,进而可能影响这一地区的生态系统碳收支和养分循环.  相似文献   
943.
为深入分析宁夏农业综合开发活动对土壤有机质的影响,认识其对气候变化的适应意义,分别于北部平原灌区、中部干旱带和南部黄土丘陵区的3个农发项目典型示范点,选取典型用地、玉米地、未利用地3种土地利用类型,分析表层10~20 cm土壤有机质的变化规律。研究发现,生态区和土地利用类型是影响土壤有机质的重要因素,并存在极显著的交互作用。研究区土壤有机质在4.53~14.70 g·kg-1范围内变化,典型用地有显著改善,平均质量分数达10.40 g·kg-1。限定生态区条件下,北部平原灌区无论水稻还是玉米利用方式下,土壤有机质含量相对未利用地都出现显著提升,但是南部黄土丘陵区3种土地利用类型间并无显著差异,中部干旱带只有甘草地土壤有机质含量显著提升,幅度高达145%。限定土地利用类型条件下,3个生态区间典型用地土壤有机质出现显著差异,但是北部平原灌区和南部黄土丘陵区间未利用地以及玉米地表层土壤有机质差异并不显著。研究区农业综合开发活动对土壤有机质储存的作用以正效应为主,但是不同农业土地利用类型在不同生态区对土壤有机质的作用不尽相同。宁夏农业综合开发活动需要综合考虑生态区水土资源特征,选取适宜的农业土地利用类型,有效提升土壤有机质含量,积极应对气候变化。  相似文献   
944.
侯颖 《生态环境》2011,20(12):1945-1949
土壤呼吸是指土壤产生CO2的所有代谢作用,是碳素由陆地生态系统进入大气的主要途径和大气CO:的重要来源,是影响全球碳循环的途径之一,它的变化可能会对大气CO2浓度产生显著的影响。城市化的推进引起世界范围内土地利用/覆盖方式的变化,这种变化对土壤的理化性质、生物学特性等产生深刻影响,从而影响土壤的呼吸作用。因此,研究城市化引起的土壤呼吸变化对于精确地估测陆地碳循环有着重要意义。国外在20世纪90年代就开始了城乡梯度上土壤碳动态的研究,而我国在这这方面的研究还处在起步阶段,尤其是关于由自然土壤转变为城市土壤后,土壤呼吸变化的机制研究较少。已有的研究表明,在干旱和半干旱地区,城市化引起土壤呼吸降低,而非干旱区则相反。此外,城市化过程中,土壤呼吸变化的方向和强度因所处的气候区域、利用的土地来源、城市内部的土地利用方式及植被类型的不同等而存在差异,但仍存在许多不确定的影响因素,如与气候变化的耦合作用等。因此,在未来城市化过程对土壤呼吸作用的研究中,应加强土壤呼吸作用的直接影响因子和间接影响因子、时空差异及其他更精细的研究。  相似文献   
945.
A lot of attention has beenfocused on workers ‘ perceptions of workplace safety but relatively little or no research has been done on the impact of job satisfaction on safety climate. This study investigated this relationship. It also examined the relationships between job satisfaction and workers’ compliance with safety management policies and accident frequency. A positive association was found between job satisfaction and safety climate. Workers who expressed more satisfaction at their posts had positive perceptions of safety climate. Correspondingly, they were more committed to safety management policies and consequently registered a lower rate of accident involvement. The results were thus consistent with the notion that workers ‘ positive perceptions of organisational climate influence their perceptions of safety at the workplace. The findings, which have implications in the work environment, are discussed.  相似文献   
946.
One of the most important ways to prevent accidents is to consider safety climate or culture. Moreover, some studies suggest that behavior contributes to 86%-96% of all injuries. This cross-sectional study took place in an Iranian petrochemical company in 2010. Vinodkumar and Bhasi’s safety climate questionnaire and an ergonomic behavior sampling checklist were the data collection tools. Cronbach’s a for questionnaire reliability was .928. With reference to the results of a pilot study, a sample of 1755 was determined for behavior sampling. We used principal component analysis (PCA) to derive the coefficient of paths in the path model and the Anderson-Rabin method to calculate factor scores. The results showed that safety climate was an effective predictor of ergonomic behavior (p < .01). They also showed the importance of decreasing the number of workers with negative safety climate. Moreover, it is necessary to promote workers’ ergonomic behaviors in the workplace.  相似文献   
947.
The main aim of this study was to develop a short questionnaire to assess work-related well-being from the organizational behaviour perspective. The short well-being questionnaire enables measuring longitudinal work-related well-being. Work-related well-being was assessed with a 147-item questionnaire covering both organizational and intrinsic factors of work-related well-being. The questionnaire consisted of 27 categories. The respondents were 114 women (65%) and 62 men (35%), mean age 39.2 years, in various occupations. From the extensive questionnaire a shorter questionnaire with 33 items was developed by principal component analysis. The Kaiser-Meyer-Olkin measure to test the sampling adequacy of 27 factor solutions varied from .62 to .91 and Cronbach’s a was .74–.94. Most K values of the shorter questionnaire were .50–.94 (p < .001). The reliability of the short version was comparable to that of the original questionnaire. The short one could also be suitable for Internet and mobile questionnaire applications.  相似文献   
948.
Abstract: Climate change, particularly the projected changes to precipitation patterns, is likely to affect runoff both regionally and temporally. Extreme rainfall events are expected to become more intense in the future in arid urban areas and this will likely lead to higher streamflow. Through hydrological modeling, this article simulates an urban basin response to the most intense storm under anthropogenic climate change conditions. This study performs an event‐based simulation for shorter duration storms in the Flamingo Tropicana (FT) watershed in Las Vegas, Nevada. An extreme storm, defined as a 100‐year return period storm, is selected from historical records and perturbed to future climatic conditions with respect to multimodel multiscenario (A1B, A2, B1) bias corrected and spatially disaggregated data from the World Climate Research Programme's (WCRP's) database. The cumulative annual precipitation for each 30‐year period shows a continuous decrease from 2011 to 2099; however, the summer convective storms, which are considered as extreme storms for the study area, are expected to be more intense in future. Extreme storm events show larger changes in streamflow under different climate scenarios and time periods. The simulated peak streamflow and total runoff volume shows an increase from 40% to more than 150% (during 2041‐2099) for different climate scenarios. This type of analysis can help evaluate the vulnerability of existing flood control system and flood control policies.  相似文献   
949.
Climate change has become a permanent feature on the global media scene and in the decision-making of policy makers. The voices of academics, scientists, politicians and commentators dominate the climate change debate, yet local knowledges and beliefs, local realities, as well as local voices and actions are essential elements of navigating the way forward. Drawing on Paton's postgraduate research, this paper broadens the current dialogue by providing a platform for grassroots Tuvaluan voices to enter the climate change debate. It explores their local realities, knowledges and beliefs, and captures what Tuvaluans hold dear – factors which must play a central role in decision-making processes. To ensure the local population is fully mobilised, it will be argued that processes for engaging local voices must build on existing forums for engagement.  相似文献   
950.
Nepal's geographical landscape of plains, hills, and mountains exposes it to severe climatic conditions. Out of the three regions, the plain, also called Terai, has the greatest risk of flooding, especially during the monsoon season when heavy precipitation coincides with snow and glacier melting from the mountains and hills. In recent years, greater water availability has increased the frequency of flooding, destroying farms, livestock, and infrastructure, hence, reducing agricultural productivity and disrupting economic activities. What makes Nepal a unique case study for climate change is its richness in water resources, propensity to flood, the percentage of poor people living in the flood prone region, and their dependency on natural resources. The lessons drawn can help when formulating pro-poor adaptation policies for other Asian and many developing countries that are as diverse, poor, and agrarian as Nepal. Using data collected through survey interviews, the study examines the ability of the poor to adapt to climate change. The study also explores the adaptive capacity of communities in the Koshi Tappu area, by examining whether or not they have the required capital assets (human, social, natural, physical, and financial capital) to remain resilient in the face of continuous climate events impacts.  相似文献   
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