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121.
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   
122.
Atmospheric surface aerosol radiative forcing (SARF) ΔF, forcing efficiency ΔFe and fractional forcing efficiency ΔFFe evaluated from cloud-screened narrowband spectral and thermal-offset-corrected radiometric observations during the Asia dust outbreak episodes in Gwangju, Republic of Korea are reported in this study. Columnar aerosol optical properties (aerosol optical depth (AOD), τ , Angstrom exponent α, mass concentration of fine and coarse mode particles) were also reported for the station between January 2000 and May 2001 consisting of 211cloud-free days. Results indicate that majority of the AOD were within the range 0.25–0.45 while some high aerosol events in which AODs ≥ 0.6 were observed during the severe dust episodes. For example, AOD increases from annual average value of 0.34 ± 0.13 at 501 nm to values >0.60 during the major dust events of March 27–30 and April 7–9, 2000, respectively. The α 501–870 nm which is often used as a qualitative indicator of aerosol particle size had values ranging from 0.01 to 1.77. The diurnal forcing efficiency ΔDFe at Gwangju was estimated to be −81.10 ± 5.14 W m −2/τ 501 nm and −47.09 ± 2.20 W m −2/τ 501 nm for the total solar broadband and visible band pass, respectively while the fractional diurnal forcing efficiency ΔFDFe were −15.8 ± 0.64%/τ 501 nm and −22.87 ± 1.13%/τ 501 nm for the same band passes. Analyses of the 5-day air-mass back trajectories were further developed for Gwangju in order to classify the air-mass and types of aerosol reaching the site during the Asia dust episodes.  相似文献   
123.
基于灾度的亚洲巨灾划分标准研究   总被引:2,自引:0,他引:2  
分析了灾害的双重属性:自然属性和社会属性。灾度是灾害社会属性的定量描述,论述了灾度在灾害分级中的应用。提出了灾度计算模型,该模型的影响因子包括:死亡人数、直接经济损失和受灾人数。收集了1954-2010之间的亚洲灾害,并应用灾度计算模型对收集到的资料进行了计算与分析。提出了亚洲巨灾标准:灾度大于8的灾害为亚洲巨灾。该标准具有计算简便、易于对不同灾害进行比较的特点。  相似文献   
124.
This article compares a range of initiatives aimed at involving people in the management of forest resources in Nepal and India. In Nepal, we focus on three categories of state-initiated programs: community forestry, the parks’ buffer zone program, and leasehold forestry. In the southern Indian state of Karnataka, we study the state-initiated Joint Forest Planning and Management program along with older institutions of leaf manure forests (Soppina betta) and historical sacred forests (Kans). We conclude that state-initiated approaches to involving communities have been limited, at best, promote standardized and relatively inflexible management practices, and lead to partial improvement in biodiversity and people’s livelihoods. When management is initiated and owned by the community, as in the case of sacred groves in India, and when other conditions are appropriate, communities can have the opportunity to demonstrate their capacity for putting effective and adaptive conservation practices in place.  相似文献   
125.
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   
126.
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   
127.
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   
128.
利用源示踪技术计算日本和韩国低层大气SO2和PSO4来源   总被引:1,自引:0,他引:1  
利用区域空气质量模式CAMx中的PAST(源示踪技术)对2010年东亚地区的总硫(SO2+PSO4)的源-受体关系进行了模拟计算. 模拟区域内共设定43个源区,其中在中国领土范围内设定了33个源区. 在源-受体关系计算中,将日本本岛分为北部、中部和南部三部分,分别设为受体区域,同时还将远离陆地的海洋背景点冲绳和韩国济州岛设为受体点.模拟结果表明,日本本岛北部、中部和南部的总硫来源存在一定的差异:日本本国的贡献率分别为73.8%、77.1%和65.9%,中国的贡献率分别为23.5%、20.2%和25.8%. 韩国本土总硫的本国贡献率为67.8%,中国的贡献率为27.2%. 对韩国济州岛和日本冲绳而言,二者总硫的本国贡献率均为26.0%,远低于日、韩两国的其他地区,不能代表国家间跨界输送的总体状况. 受体区域跨界输送的总硫季节变化明显,而且各区域的变化趋势也并不一致,其中日本南部地区和韩国本土1月最强,7月最弱;日本北部和中部地区在4月最强,1月最弱. 跨界传输的总硫对日本和韩国总硫贡献量小于2.5 μg/m3.对于日、韩两国影响较大的中国源区主要为山东、河北、江苏、辽宁等地,各源区对于日、韩总硫贡献量的季节变化明显. 东亚地区低空总硫的传输通量空间分布与利用CAMx模拟的2010年日本和韩国总硫的源-受体关系结果相一致.   相似文献   
129.
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   
130.
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   
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