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171.
The Extensive Mesozoic volcanics of Southeast China ontinent, including Zhejiang, Fujian and Guangdong provinces, possessing unique temporal and spatial features is called the volcanic zone of Southeast China Continent (coast),it belongs to a part of circum-Pacific Mesozoic and Cenozoic volcanic belt.It was believed that this volcanic zone could be compared with that of Andesian active continental margin. But based on recent study the author found many evident difference between the volcanic zone of southeast China and Andesian volcanic zone of American. The former has unique features.  相似文献   
172.
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   
173.
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   
174.
索尔库里盆地位于青藏高原东北缘,柴达木盆地的北部,气候恶劣、交通不便,研究资料匮乏。通过对索尔库里北盆地彩虹沟剖面新近纪中后期沉积物的古地磁测年和碳酸盐碳氧同位素质谱分析,揭示了索尔库里盆地13.5~2.5 Ma长序列气候演变过程。13.5~9.2 Ma时期相对冷干,9.2~5.3 Ma时期相对温湿,5.3~3.9 Ma时期相对暖湿,3.9~2.5 Ma时期再次转为冷干。11 Ma左右,青藏高原东北缘隆升到阻止印度洋暖湿气流向北方运输的高度,地处走滑盆地的索尔库里地区逐渐变得极其干旱,标志着亚洲内陆干旱化在此背景下开始。红粘土磁化率和碳氧同位素变化等证据显示,西风在本区贯穿始终,而季风的出现加剧了亚洲内陆古气候的干湿更迭,对区域及全球古气候重建具有重要意义。  相似文献   
175.
176.
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   
177.
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   
178.
Tai Lake (Ch: Taihu) has attracted international attention forcyanobacteria blooms. However, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The results of research demonstrate how socio-economic development affected quality of water and how it has been improved by anthropogenic activities. This study described variability in indicators of water quality in Tai Lakeand investigated thedrivers. Significant relationships existed between concentrations of annual mean total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (COD) and biological oxygen demand (BOD), and population, per capital gross domestic production (GDP) and sewage discharge (p?<?0.05). However, mechanisms causing change varied among TN, TP, COD and BOD. Before 2000, the main contributors to increases in concentrations of TN were human population, GDP and volumes of domestic sewage discharges. After 2000, discharges of industrial sewage become the primary contributor. After 1998, the regressions of annual mean TN, TP and COD on per capital GDP, population and domestic sewage discharge were reversed compared to the former period. Since 1999, an apparent inverted U-shaped relationship between environmental pollution and economic development has developed, which indicated that actions taken by governments have markedly improved quality of water in Tai Lake. The statistical relationship between BOD and per capital GDP didn’t conform to the Kuznet curve. The U-shaped Kuznet curve may offer hope for the future that with significant environmental investments a high GDP can be reached and maintained without degradation of the environment, especially through appropriate management of industrial sewage discharge.  相似文献   
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