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21.
“十五”期间,重点项目档案管理工作成为地震档案管理工作的重要组成部分,重点项目档案形成周期长,数量大,知识密集、覆盖面广,科技含量高,给档案的收集、归档造成一定的难度。为了加强重点项目档案的管理工作,提高归档质量,要采取切实可行的措施,保证重点项目档案的完整、准确、系统,为防震减灾事业服务。  相似文献   
22.
从我国自然保护区所面临的经费困难和开展生态旅游的现状入手 ,概述了生态旅游资源的价值评估法和加拿大国家公园使用者收费情况 ,并探讨了我国自然保护区生态旅游资源价值实现的若干方式  相似文献   
23.
以MATLAB应用软件作为开发平台介绍了黑色金属挤压力智能化计算软件的开发方法,设计的界面友好,操作简单,可实现冷挤压力的智能化计算以及工艺参数优化设计。软件计算的挤压力的大小与传统方法比较相对误差小于5%。  相似文献   
24.
Background: Road traffic injuries (RTIs) are a serious epidemic that claims more than a million lives across the globe each year. The burden of RTIs is particularly pronounced in Africa and other low- and middle-income countries. The unfavorable disparity of the burden of road trauma in the world is largely attributable to unsafe vehicles, lack of appropriate road infrastructure, and the predominance of vulnerable road users (VRUs) in developing countries. However, little research exists in northern Ghana to highlight the scale and risk of death among road users.

Objective: The objective of this research was to establish the relative risk of death among road users in northern Ghana.

Methods: Crash data from police reports between 2007 and 2011 were analyzed for the Upper Regions of Ghana. Conditional probabilities and multivariable logistic regression techniques were used to report proportions and adjusted odds ratios (AORs), respectively.

Results: Generally, crashes in northern Ghana were extremely severe; that is, 35% of all injury related collisions were fatal. The proportion of fatal casualties ranged between 21% among victims of sideswipe collisions and 41% among pedestrians and victims of rear-end collisions. Though males were 6 times more likely to die than females overall, females were more likely to die as pedestrians (90% of all female casualty deaths) and males were more likely to die as riders/drivers (78% of all male casualty deaths). Pedestrians were 3 times more likely to die (odds ratio [OR] = 3.1; 95% confidence interval [CI], 2.4 to 4.1) compared with drivers/riders. Compared with drivers, the odds of death among cyclists was about 4 times higher (AOR = 3.6; 95% CI, 2.3 to 5.6) and about 2 times higher among motorcyclists (AOR = 1.6; 95% CI, 1.2 to 2.2). Compared with casualties aged between 30 and 59 years, children under 10 years and those aged 60 years and above were independently 2 times more likely to die in traffic collisions.

Conclusion: Provision of requisite road infrastructure is vital for the safety of VRUs in northern Ghana. Cycle paths and lanes (for cyclists) as well as sidewalks (for pedestrians) in particular will separate VRUs from motorists and improve their safety. Enforcement of traffic laws particularly regarding helmet use, speeding, and alcohol use will be beneficial. Introduction of the demerit points system in the enforcement of traffic regulations may have significant deterrent effects on road users who have the penchant for violating traffic regulations. Road safety education is also required to create responsible road users.  相似文献   

25.
我国典型陆地生态系统固碳重要区范围界定   总被引:1,自引:1,他引:0       下载免费PDF全文
全球变暖已成为当今最主要的全球性环境问题之一,建立固碳重要区也是应对全球气候变化的重要途径之一.根据我国陆地生态系统现状以及固碳相关的最新研究结果和政府文件,以森林、草地生态系统为主要研究对象,采用GIS空间叠置分析方法,界定我国典型陆地生态系统固碳重要区(注:涉及“全国”的各要素范围均未包含港澳台地区)的空间范围.研究结果:固碳重要区评价指标体系包括生态系统碳储量、碳汇和固碳潜力3个核心因子,界定过程包括界定范围选择、固碳高值区识别、固碳重要区范围确定和分区命名等步骤.在全国尺度界定了森林、草地两大类共计20个固碳重要区,总面积285.6×104 km2.其中,森林生态系统固碳重要区主要分布在我国东北部、西南部的深山区和东南部的山地丘陵,草地生态系统固碳重要区主要分布在内蒙古高原中东部、新疆西北部山地和青藏高原东南部.固碳重要区面积占全国国土总面积的29.8%,所提供的NPP(净初级生产力)量占全国NPP总量的40.7%,固碳能力是全国平均水平的1.37倍.固碳重要区范围界定结果符合“以较小面积获取较大服务”原则,适于作为我国实现碳减排目标的优先保护区域.   相似文献   
26.
Understanding spatial and temporal variability in the distribution of species is fundamental to the conservation of marine and terrestrial ecosystems. To support strategic decision making aimed at sustainable management of the oceans, such as the establishment of protected areas for marine wildlife, we identified areas predicted to support multispecies seabird aggregations in the Timor Sea. We developed species distribution models for 21 seabird species based on at‐sea survey observations from 2000–2013 and oceanographic variables (e.g., bathymetry). We applied 4 statistical modeling techniques and combined the results into an ensemble model with robust performance. The ensemble model predicted the probability of seabird occurrence in areas where few or no surveys had been conducted and demonstrated 3 areas of high seabird richness that varied little between seasons. These were located within 150 km of Adele Island, Ashmore Reef, and the Lacepede Islands, 3 of the largest aggregations of breeding seabirds in Australia. Although these breeding islands were foci for high species richness, model performance was greatest for 3 nonbreeding migratory species that would have been overlooked had regional monitoring been restricted to islands. Our results indicate many seabird hotspots in the Timor Sea occur outside existing reserves (e.g., Ashmore Reef Marine Reserve), where shipping, fisheries, and offshore development likely pose a threat to resident and migratory populations. Our results highlight the need to expand marine spatial planning efforts to ensure biodiversity assets are appropriately represented in marine reserves. Correspondingly, our results support the designation of at least 4 new important bird areas, for example, surrounding Adele Island and Ashmore Reef. Pronostico de la Distribución Espacial de una Comunidad de Aves Marinas para Identificar Áreas Prioritarias de Conservación en el Mar de Timor  相似文献   
27.
介绍了重点排放源及区域环境介质汞污染防治监控方案,做了可行性分析,希望对汞污染防治有所启发。  相似文献   
28.
: The National Wild and Scenic River Act of 1968 was designed to protect the nation's unique waterways. This Act, however, has been criticized for negatively affecting areas it was intended to protect. Findings, based on field investigation in the Upper Mississippi River basin suggest that designation may serve as a factor for increasing recreational use levels on the protected rivers. This study discusses the social and recreational consequences of designating rivers and the attitudes of river users regarding designation.  相似文献   
29.
ABSTRACT: Transboundary water conflicts occur under four circumstances. Because water is mobile, more than one political unit or owner has power to use water as it sequentially moves through the hydrologic cycle. Even when water doesn't move, jurisdictional conflicts occur because multiple political units regulate water simultaneously. When a river is a boundar uncertainty of ownership or jurisdiction occurs as the river shifts its course through natural processes. Lastly, limitations on who may use water may be imposed by export bans or more indirect measures like taxation. Legal solutions to transboundary conflicts are limited to litigation, legislation, and negotiated agreements. This paper examines the judicial solution.  相似文献   
30.
ABSTRACT: Grain transportation is a major economic activity on the multiple use Snake-Columbia River System. Congress is currently considering increased transportation user fees aimed at recapturing federal expenditures for waterway operations and maintenance. Three types of fee structure and four levels of cost recovery are evaluated using a network program model. In each case traffic is diverted away from the river to other Puget Sound ports via truck and rail transport modes. Grain shippers in the region will be adversely affected by a higher transport bill. The Lower Columbia River port economic activities will be negatively affected; however, competitive uses of the river, recreation, and hydroelectric generation will likely benefit modestly.  相似文献   
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