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121.
Though characterized by a scarcity of water, West Asia and North Africa region has a large number of wetlands of various types supporting a rich biodiversity. However, the government efforts to reverse the trend of wetlands degradation fall short of the policy goals due to various reasons. The paper outlines the priorities for wetlands conservation in the region.  相似文献   
122.
东亚地区硫污染物的空间分布特征   总被引:4,自引:0,他引:4  
利用一个硫沉降模式分析了东亚地区SO2和SO42-浓度的空间分布及其特征.不同天气条件下,SO2和SO42-的浓度不同,高层SO2和SO42-的浓度分别为04—10μg/m3和02—05μg/m3;中层为40—100μg/m3和20—60μg/m3;近地层为40—300μg/m3和20—80μg/m3.分析表明,近地面浓度分布受源的影响比较明显,高层的浓度分布与湿清除过程密切相关,其浓度的低值区与降水区和云区有较好的对应.中层浓度分布体现了源、中层气流及湿清除的共同作用.  相似文献   
123.
During the last 30 years, growing demand for science-based policy making has contributed to the mobilization of scientific cooperation alongside transnational political arrangements for addressing environmental issues. Following the contemporary trend toward regionalizing environmental policy and practice, many of these scientific joint efforts have focused on a regional scale. This article examines regional scientific cooperation in the context of the institutionalization of mountain regions in Europe. Such cooperation can be observed from the Pyrenees to Central Asia, albeit with a degree of variation that largely remains unexplored in scientific research. Sometimes scientific cooperation served to lay the groundwork of a mountain policy initiative, other times it appeared in its wake; some examples appear as loose networks of individual scientists, others are set up as formalized monitoring and observation centers; finally, some scientific joint efforts are formally linked to, or incorporated in a mountain policy initiative, while others are largely independent. The article proposes a new typology for understanding the interactions between regional scientific mobilization and regional policy making and provides up-to-date portraits of six main cases.  相似文献   
124.
Mercury emissions from forest fires in countries bordering the Mediterranean Sea have been estimated on the basis of satellite observations for the year 2006. The assessment has been done by means of the Moderate Resolution Imaging Spectroradiometer (MODIS) products (MOD12Q1, MOD14A2, MOD15A2, MOD44B). Estimates show that wild fires have burnt 310,268 ha in the Region, affecting by 45% the Mixed Forest and by 37% the Evergreen Needleleaf Forest and the Evergreen Broadleaf Forest. The amount of biomass burned was about 66,000 Mg for the Evergreen Needleleaf Forest, 72,000 Mg for the Evergreen Broadleaf Forest and 196,000 Mg for the Mixed Forest. The total amount of mercury released to the atmosphere in the Mediterranean countries accounted for 4.3 Mg year−1 with Italy, France, Austria, Bulgaria, Algeria, Spain and Croatia being the most contributing countries with annual emission ranging from 330 to 970 kg year−1. The maximum release of Gaseous Elemental Mercury (GEM) and particulate mercury (Hg(p)) in the region occurred in July with 1,218 kg. The uncertainty of our estimates is comparable with that associated to current assessments of mercury emissions from major industrial sources.  相似文献   
125.
In the second half of 1997, large areas in Southeast Asia were severely affected by a smoke-haze pollution episode caused by the emissions of an estimated 45,600 km2 of vegetation that burnt on the Indonesian islands Kalimantan and Sumatra. To document the impacts of these fires on air quality, data for total suspended particulate matter (TSP) and for particulate matter below or equal to 10 microns in diameter (PM10) from selected sites in Indonesia, Malaysia and Singapore are analysed in this paper. These data are supplemented by meteorological data, satellite images and a summary of related research. TSP was above 2,000 μg m–3 for several days in Indonesian locations close to the most extensive fire activity. In Malaysia and Singapore, ambient particle concentrations increased to several times their average September levels. Characteristically for emissions from vegetation burning, the additional atmospheric particle loading during the smoke-haze episode was predominantly due to an increase of the fraction below or equal to 2.5 microns in diameter (PM2.5). Due to the dominance of respirable particles (PM2.5) in the smoke-haze, air quality reporting based on TSP or PM10 may be inadequate to assess the health risk. Upgrading of PM2.5 monitoring facilities is therefore needed. Reducing the probability of similar smoke-haze events in future would require appropriate fire use and smoke management strategies. Electronic Publication  相似文献   
126.
Monitoring of the occurrence of sandstorms and dustfallphenomena from 1997 to 2000 was carried out. We refer tosandstorms, duststorms and blowing sand as the phenomenaoccurring in the source region, while significant dustfall is thephenomenon that occur in the sink area. It was noted that while the sandstorms in deserts and loess in NW-N China and Mongolia occurred any time during the year while severe sandstorms occurred frequently from March to May after the springthaw. The wind erosion in the source region usually occurred withwind speeds greater than 8 ms-1. However, severe sandstorm phenomenon occurred with wind greater than 15 ms-1 for at least 3 hr or more. In the source regions, sandstorms occurred over60–120 days per year. In Mongolia, the observation of thenumber of sandstorm days decreased due to the increase in rainy days.When a dust cloud from a desert reached the sink region,significant dustfall in the Korean Peninsula occurred due tothe lack of strong winds. We defined the episode ofsignificant dustfall (SD) with the following values: TSP250, PM10 190 g m-3 and visibility 6.5 km or less. In Korea, 8–12 episodes of SD occurred per yearwith 12 to 22 SD days. The maximum concentrations of TSP recorded were 989–1396 g m-3 with PM10 values of 861–996 g m-3 and with the lowestvisibility of 1.4–1.6 km.  相似文献   
127.
广东省正计划以20年时间赶上韩国、新加坡、台湾、香港“亚洲四小龙”的经济水平。本文分析了追赶“亚洲四小龙”的科学依据,提出了必须重视下列问题。1.经济高速发展,必须重视水源开发和保护;2.面向国际市场,建立外向型经济,必须得到法律的认可和保护,这样才能发挥海洋综合效益。3.经济高涨,城镇化进程必然加速,因此,城镇必须合理布局,城镇总体规划须有超前性、起点高、要求严。  相似文献   
128.
129.
This article reviews water-related urban environmental conditions in Southeast Asia. It argues that the development of urban environmental challenges in the region follows a unique pattern compared with those experienced in the now developed world. The new pattern is defined by the so called time–space telescoping of the development process. The process of time–space telescoping reduces the levels of income at which environmental challenges emerge and forces their appearance in a simultaneous fashion, as sets of problems. During previous eras, cities experienced sequential environmental transitions. Urban water-related environmental burdens emerged on local scales and expanded geographically and temporally in impact, with growing levels of affluence. Moreover, certain environmental challenges appeared later in economic growth because the technologies and practices that induced these problems emerged at higher levels of income. The article has two main findings. First, except for wealthy urban centers, for example Singapore, cities in the region are experiencing multi-scaled water burdens simultaneously. Second, low-income and middle-income cities are experiencing burdens at lower levels of income than did their contemporaries in the north.
Peter J. MarcotullioEmail:
  相似文献   
130.
首届"东北亚中亚区域可持续发展国际论坛"在北京召开。与会专家围绕着"全球气候变化背景下东北亚和中亚区域可持续发展"主题展开充分讨论,并形成重要研究结论。来自中国、俄罗斯、蒙古国、乌兹别克斯坦和以色列等国20多个研究机构的7位科学院院士、9位研究所所长和200多位专家学者讨论认为,面对积极应对全球变化的国际态势,加强东北亚中亚可持续发展国际合作研究具有重大战略意义,并向东北亚和中亚地区各国政府和专家学者发出共同倡议。此次国际论坛对加强东北亚和中亚地区在全球变化背景下资源生态环境与可持续发展科学问题与规律的国际合作研究具有重要推动作用。  相似文献   
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