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181.
RCP4.5情景下预测21世纪南海海平面变化   总被引:2,自引:1,他引:2  
张吉  左军成  李娟  陈美香 《海洋学报》2014,36(11):21-29
结合卫星高度计资料和SODA温盐数据,本文利用CCSM(Community Climate System Model version4)气候系统模式在代表性浓度路径RCP4.5情景下对全球海平面变化趋势的预测模拟结果作为强迫场,用POP模式模拟预测21世纪南海海平面长期趋势变化及空间分布。模拟结果显示,在RCP4.5情景下,南海海域在21世纪末10年平均海平面相对于20世纪末10年上升了15~39cm,明显上升海域位于中南半岛东部的南海中部、南部海域和吕宋海峡东西两侧海域,上升值最大可达39cm。如果加上格陵兰和南极等陆地冰川融化的影响,21世纪南海总海平面上升值将可能达到35~75cm。南海比容海平面明显上升区域位于吕宋岛东面的深水海域,广东沿岸流和吕宋冷涡之间海域,以及中南半岛东南部海域。总比容海平面的变化主要来自热比容,盐比容贡献比较小。南海南部和西部比容海平面上升速率较低,如加里曼丹岛西北侧、泰国湾和海南岛西侧有下降趋势。  相似文献   
182.
海岸带综合管理框架体系研究   总被引:12,自引:2,他引:10  
随着经济的发展,海岸带以其丰富而又独特的资源优势而成为开发的热点,环境压力随之出现由于海岩带生态系统的多样性和复杂性,原来的单因素管理已经不能适应发展的需要,必须要求一种全面的、综合的、系统的方法来进行管理,即海岸带综合管理(Integrated Coastal Zone Management,即ICZM)。本文通过对海岸带综合管理的概念分析,从环境经济学的角度分别对资源的功能、利用和价值进行了论  相似文献   
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184.
Spatial and temporal changes in ecosystem services(ESs) are driven by two types of factors: environmental factors and trade-offs/synergies between services. In the ecological conservation red line(ECRL) area, in which national ecological security and social sustainable development are guaranteed, it is particularly important to clarify the driving mechanism of ESs for the management of ecosystems. In this study, soil conservation, water yield, and carbon sequestration in Beijing’s ECRL area are ...  相似文献   
185.
对遵义CINRAD/CD新一代多普勒天气雷达运行6年多来发生的8次方位伺服系统驱动电源故障维修工作进行归纳总结。根据故障现象细微差别,将其归纳为3类,并对应分析故障原因,找出具体维修措施,以便于本站维修经验的积累和国内其他同型号雷达维修技术人员参考。  相似文献   
186.
Many environmental pollution issues from highway runoff increasingly become a serious concern, which has been revealed by many previous studies. However, very less information is available on the distribution characteristics of pollutants and their mutual influence in highway runoff. In this paper, the partitioning of pollutant and particle size distribution were investigated based on the initial road runoff of 47 rainfall events from July 2007 to May 2009 on the Lukou section of the Nanjing Airport Expressway, China. This study is emphasizing on the analysis of the mutual impact of pollutant distribution and the relationship between particle size and pollutant distribution. The impact of rainfall characteristics, water temperature, and pH values in runoff samples on the pollutant distribution was also studied. Result shows that partitioning of different pollutants was varying significantly. Volume of particles in different sizes was different, with the highest volume of particles of 21–75 µm size. The distribution of COD highly affected the distribution of TN, and somewhat promoted the distribution of Pb in particles. TP, Pb, and Cd promoted distribution of each other's in particles. There was better competition among Zn, Cu, and Cd, when heavy metals combined with particles. The particles ranged between 21 and 75 µm size had an obvious impact on the distribution of COD, Pb, and TN in the particulate matter. TP in the particulate matter mainly distributed in particles ranged in 151–300 µm size. Rainfall duration significantly affected the Pb in particulate matter. The distribution of Zn in the particulate matter mostly was affected by pH values.  相似文献   
187.
As the population and economy boom, more and more dams are being built in the Mekong River basin. Previous studies have revealed that Manwan Dam had little influence on the runoff–SSC (suspended sediment concentration) relationship, and the sediment load was relatively stable over the past 40 years. However, little is known at present on the relationship among monsoons, El Niño Southern Oscillation (ENSO), precipitation, runoff, and the impact of dams on the delta dynamics. A comprehensive hydropower GIS database covering the entire Mekong basin is presented in this study. Mann–Kendall trend analysis showed no significant change in precipitation and runoff over the past 50 years. Spectral analysis showed that the runoffs of the middle to lower reach of Mekong River are correlated with the Indian Monsoon, where as the East Asian Monsoon's influence is mainly on the lower reach. With another 200 new dams to be added to the basin in the next couple of decades, changes are expected in both hydrological regime and delta dynamics. On one hand, the runoff showed a closer connection with the regional precipitation and ENSO in the post‐dam period (1993–2005) than in the pre‐dam period (1950–1993). Such a relationship is expected to be even closer when more dams are completed. On the other hand, both daily maximum and minimum water levels on the delta plain have shown an abrupt drop since the end of 1994. This reduced water‐level gradient between the river and sea inevitably weakens the sediment discharge to the coast, which might intensify the ongoing coastal erosion on the eastern part of the delta plain. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
188.
In order to investigate the impact of urbanization and industrialization on surface water quality,a pilot study of Panzhihua mining town was carried out.The urbanization of Panzhihua region was dominated by industry development and population growth.The level of urbanization showed that it was 18.44% in 1965,and reached 45.99% in 1983.Then,it reached 53.71% in 2005,so the urbanization process was very rapid in Panzhihua region.In the process of industrialization,the level of industrialization was fluctuated...  相似文献   
189.
Sebastiscus marmoratus larvae were exposed to waterborne polycyclic aromatic hydrocarbons (PAHs) containing 3-5 rings, benzo[a]pyrene (BaP), pyrene (Py) or phenanthrene (Phe), respectively at 0.01, 0.1 and 1 μg L?1. Cumulative mortality, frequency of dorsal curvature and rate of pericardial and yolk sac edema in larvae treated for 8 days were significantly increased in a dose-dependent manner. All three PAHs resulted in reduction of the lower jaw, and the extent of reduction increased with increasing concentrations of the PAHs. Na+/K+-ATPase and Ca2+-ATPase activity in larvae exposed to the three PAHs were all significantly inhibited in a dose-dependent manner. Analysis using the Pearson correlation coefficient indicated a significant correlation between the rate of the dorsal curvature and edema and the inhibition of Na+/K+-ATPase and Ca2+-ATPase activity, suggesting that the developmental defects caused by PAHs were related to their inhibition of Na+/K+-ATPase and Ca2+-ATPase activity.  相似文献   
190.
基于Google地图API接口,采用Oracle数据库管理和AJAX,JavaScript技术,进行地震综合信息服务系统的平台搭建.结果表明该系统具有快速、全面、易操作的特点,解决了目前开发GIS平台数据昂贵、系统维护困难等问题,为用户了解震情提供了良好的平台.  相似文献   
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