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61.
利用1964年-2010年气象资料,采用回归分析和滑动t检验等方法,分析中国东北地区典型开垦型农场气温和降水量的变化特征。结果显示:47年来,八五九农场气温在波动中呈显著上升趋势,年均气温线性倾向率为0.14℃/10 a;年降水量也在波动中呈现上升趋势,其线性倾向率为7.51 mm/10 a。滑动t检验结果表明,20世纪70年代末期是八五九农场气温明显由冷向暖转变的分界点;而年降水量在70年代末期由少向多发生较为显著的变化。  相似文献   
62.
塔里木盆地南缘保存有中国西北地区厚度最大的黄土,是详细研究亚洲内陆极端干旱 区以及塔克拉玛干沙漠形成演化的理想材料。但是,目前对该地区黄土堆积粒度特征系统的研 究还相对较少,对粒度指标的古环境意义仍存有不同的认识。通过对207 m 黄土岩芯的粒度分 析发现,西昆仑山黄土的粒度组成比较均一,分选较好,主要以粗颗粒物质为主,细颗粒含量 极少,并具有典型的风成成因特征。此外,西昆仑山黄土粒度1 Ma 以来呈现出持续变粗的趋势。 通过与其他气候指标的对比,这种变粗的趋势可能主要反映了中更新世以来亚洲内陆逐步增强 的干旱化过程。  相似文献   
63.
Water Resources of Central Asia and Adaptation Measures for Climate Change   总被引:1,自引:0,他引:1  
A large part of the Central Asian region is located within the inner flow of the Aral Sea basin. The water resources are formed from renewed superficial and underground waters of natural origin, and also with returnable waters. The intensive increase of water intake, that took place in the second half of the twentieth century caused practically complete assimilation of the river inflow. That was the main reason for the Aral Sea crisis. On the basis of the analysis of long periodical rows of observation by meterological and hydrological stations, the estimation of regional water resources and calculations of changes of some components of the hydrological cycle due to the expected climate changes are presented. Measures for adaptation in the southern part of the Aral Sea region are considered.  相似文献   
64.
The wetlands play an important role in carbon storage, especially at high latitudes, at which they store nearly one-third of global soil carbons. However, few studies have investigated the emissions of CO(2), CH(4) and N(2)O in the long-term, especially effects of freeze-thaw cycles on these gases emissions in freshwater marsh ecosystems. In this paper, we collected greenhouse gas emission data from a freshwater marsh area in China for 4 years, evaluated their release variables and speculated on their potential atmospheric impact. For this paper, we report on the CO(2), CH(4) and N(2)O emission rates recorded from June 2002 to November 2005 in the Sanjiang Plain of northeast China. We measured their interannual variations and fluctuations, as well as factors affecting their emissions, and estimated their regulation and freeze-thaw cycle impacts. Our results revealed obvious CO(2) and CH(4) emission fluctuations during the winter months, and during the freeze-thaw cycle, and a strong interannual variation during the growing season. Overall, we documented a close relationship between the CO(2) and CH(4) emissions, implicating some regulatory commonality. We determined that the marsh was a N(2)O sink during the winter, but a significant source of N(2)O during the freeze-thaw cycle as the temperature increased, especially in early summer. During the thaw-freeze period, the N(2)O levels were positively correlated with the water depth. Additionally, water depth greatly governed the interannual variation of the N(2)O emissions from the marshes during the thaw-freeze period.  相似文献   
65.

Introduction

Fatalities from traffic accidents in less-motorized societies are an important global issue. We aimed to characterize the geographic differences of fatalities in such societies to facilitate the development of targeted interventions.

Method

This study linked police reports, hospital data, and vital registration data from Taiwan with special reference to accident factors in pre-hospital deaths and medical care in hospital deaths.

Results

A higher percentage of pre-hospital deaths were observed following rural as compared to urban traffic accidents. The deaths due to rural accidents can be attributed to lower use of restraints (i.e., helmets or seat belts), lower percentage of motorcyclists, and more highway accidents. A higher percentage of victims in rural accidents were transported to distant medical centers rather than to local hospitals.

Conclusion

Specific interventions, such as intelligent emergency medical systems, campaigns for helmets and seat belt usage, enforcement of helmets and seat belt use, and speed control measures should be targeted to rural areas.

Impact on industry

Cooperation between the vehicle industry and emergency medical providers in rural traffic accident rescue teams may decrease the numbers of deaths in these regions.  相似文献   
66.
盐碱泡沼广泛分布于东北地区的中、西部,是该区域宜渔国土资源的主要类型之一.根据1988~1995年东北松辽平原农业综合开发的实践,本文以大安市试验示范区为例,初步介绍了盐碱泡沼渔业开发的6项主要技术措施,以供同类地区借鉴。  相似文献   
67.
A procedure is outlined which allows consideration of both objective and subjective indicators to establish priorities in plan implementation of water resource development. The objective procedure utilizes stepwise multiple discriminant analysis to predict community performance regarding planned project implementation, based on previous project implementation in the Northeast. The subjective procedure incorporates prior probabilities developed by the planner, based on observation and experience gained through the planning process. The proposed analysis could eliminate waste through better allocation of planning funds to implementation studies exhibiting higher probability of early implementation.  相似文献   
68.
东北地区资源型工业发展对策   总被引:1,自引:0,他引:1  
任启平 《资源开发与市场》2004,20(4):243-245,251
资源型工业在东北地区经济发展中占有重要的地位,是地区经济发展的支柱和解决社会就业的主力.在回顾东北地区资源型工业发展历史的基础上,分析了发展中存在的问题和不足,指出振兴东北地区和发展资源型工业的必要性,最后提出了要通过建立支撑系统、优化生产体系、利用国际市场、实行集团化经营、调整产业结构、实现可持续发展等来发展东北地区资源型工业的相应对策.  相似文献   
69.
本文阐述了环境保护在推进东北老工业基地振兴中的监督与服务工作。  相似文献   
70.
The contemporary copper cycle of Asia   总被引:11,自引:1,他引:10  
A regional stock and flow model for an industrial metal was developed based on the substance-flow framework. Using this model, the contemporary copper cycle of the Asian region was constructed by aggregating country-level production and import and export data for different stages of the copper cycle. The reliability and availability of data were assessed both qualitatively and quantitatively. Asia as a region is a net importer of copper. There is a significant build-up of copper in use at a rate of nearly 3TgCu/year. The per capita generation of copper waste (0.4kgCu/(capita-year)) and the rate of secondary recovery of copper are low compared with Europe and North America. Japan's rates of use, waste generation, and recycling of copper are all much larger than the continental average. A tremendous potential exists in the region to utilize the copper content of the in-use reservoir, and subsequently to enhance copper recycling rates in the future. A set of metrics for the copper cycle is suggested in order to address sustainability issues related to resource policy and the environmental management of copper.  相似文献   
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