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51.
通过对南海大洋钻探ODP第184航次的ODP1143站和ODP1146站以及中德合作"太阳号"95航次的南沙海区17957-2柱状样中微体化石进行定量分析,提取了近18MaB.P.以来南海上部海水垂向结构的变化.结果发现11.5~10.6MaB.P.之间和3.6~3.3MaB.P.以来南海温跃层深度的南北梯度明显增大,指示了西太平洋暖池雏形的开始和现代暖池的最终形成,且分别对应于印度尼西亚海道和巴拿马地峡的关闭.此后,南沙海区的温跃层深度自约0.9MaB.P.逐渐变浅,至约0.15MaB.P.又再变深,反映了西太平洋暖池的减弱和再次加强.因而,晚新生代西太平洋暖池的形成和演化呈现阶段性. 相似文献
52.
GRIB2介绍及解码初探 总被引:1,自引:0,他引:1
由于气象数据种类不断增多,对数量和质量的要求越来越高,而字符编码的局限性使得字符编码不能很好地满足这样的需求。WMO建议逐渐由字符编码向表格驱动码过渡。该文介绍了表格驱动码中的一种,即二进制格点加工数据(GRIB码)。首先介绍GRIB码的第1个版本(GRIB1)的编码格式,使用的模板技术及GRIB1目前在使用过程中的一些缺陷。然后着重分析了GRIB码的第2个版本(GRIB2)新的编码格式和特点,以及GRIB2在表示丰富的数据方面的优越性,最后对GRIB2解码过程中需要注意的一些问题进行了阐述。 相似文献
53.
Belowground carbon balance and carbon accumulation rate in the successional series of monsoon evergreen broad-leaved forest 总被引:4,自引:0,他引:4
ZHOU Guoyi ZHOU Cunyu LIU Shuguang TANG Xuli OUYANG Xuejun ZHANG Deqiang LIU Shizhong LIU Juxiu YAN Junhua ZHOU Chuanyan LUO Yan GUAN Lili LIU Yan 《中国科学D辑(英文版)》2006,49(3):311-321
The belowground part of terrestrial ecosystem is a huge carbon pool. It is believed that of the total 2500Gt carbon stored in global terrestrial ecosystem, soil carbon storage within the 1 m surface layer ac- counts for 2000Gt, which is 4-fold of vegetation car- bon storage[1,2]. Compared with the carbon in the vegetation, carbon in the deep soil layers is much more stable, and it will stay in soil profile permanentlyunless geological vicissitude occurs. Essentially, forest restoration is the… 相似文献
54.
The structural activities took place extensively in the Asia continent during the Cenozoic era owing to the strong continent-to-continent
collision and continuous compression between the India Plate and the Eurasia Plate. Huang Jiqing called such structural activities
Himalayan movement. China’s sedimentary basins developed and took shape mainly during the Himalayan movement period. It is
also the main period for formation and development of the oil and gas reservoirs. Of 366 large and medium-sized oil and gas
fields currently found in China, 212 reservoirs were formed in the Neogene-Quaternary period. The proportion is as high as
68.2%. The oil and gas migration and accumulation in the latest geological period, which were controlled by the times, properties,
styles and strength of the Himalayan movement, took place mainly in eight regions, such as the low uplift area of Bohai Sea,
the onshore faulted sag area of Bohai Bay, anticlinorium zone in Daqing, the foreland fold-and-thrust belt in West China,
the tilted structural zone in West China, the cratonic palaeohigh in the Tarim Basin, the zone of fault and fold belt in the
East Sichuan Basin, and the biological gas zone in the East Qaidam Basin. The oil and gas pool formations in those regions
have their own characteristics. With the great potential and broad prospect, those regions are the main exploration areas
in China in the future. 相似文献
55.
西太平洋暖池基本特征及其对气候的影响 总被引:15,自引:0,他引:15
本文在大洋暖区物理气候图集编制以及大洋暖池指数建立的基础上,重点分析研究了西太平洋暖池区的基本特征;大洋暖池指数的建立及暖池气候特征;西太平洋暖池与西太平洋副热带高压的关系;西太平洋暖池与厄尔尼诺的关系。 相似文献
56.
Three provenances ofPappophorum caespitosum, a forage native grass from the temperate arid region of Argentina, were studied to gain a physiological knowledge of the seasonal organic N status in response to adequate water supply and water stress conditions; and to assess the extent to which variations in the N status between these provenances arise under different water regimes. Plant part samples were analysed for free and bound organic N fractions. Water shortage resulted in a significant depression of plant growth in all provenances. Total N concentration declined along the annual cycle in both water treatments, but it was higher under water stress. The size of the free N pool was very large, suggesting that it may act like an osmoticum. Nitrogen use efficiency increases along the growing period, while the rate of N intake and the specific leaf N content decrease. Variability was found between provenances in most of the physiological and biochemical traits examined under both water regimes. 相似文献
57.
黄河是多沙性河流,引黄必带进大量泥沙,沉沙池沉粗排细,能有效处理泥沙。当沉沙池淤满,失去自流沉沙作用时,采用"以挖待沉"可以延长灌区运行年限,但没有扬水沉沙方案优越。根据黄河下游地上河的特殊地貌条件,如果能在河漫滩上建沉沙池,可以解决沉沙占地的难题。 相似文献
58.
HE Ying ZHU Xingguo Department of Geology Northwest University Xi''an Shaanxi XU PeicangXi''an Institute of Geology Chinese Academy of Geological Sciences Xi''an Shaanxi 《《地质学报》英文版》1998,72(2):191-197
Types of polymerized molecular network structure and degree of bond breakdown for glass phases of magmatic inclusions and glassy matrix in volcanic rocks from the Shengli oilfield have been defined by the laser Raman spectroscopic investigation. There are significant differences in types of polymerized molecular network structure and degree of bond 'breakdown of the magmatic glass phases between the non-CO2 and COa gas pools: magmatic glass phases of fluid inclusions and matrix in volcanic rocks from the CO2 gas pool contain more sheet network molecules and have a greater degree of bond beakdown than those from the non-CO2 gas pool; and when gas bubbles occur in evolving magma, magma saturated with volatile components has more sheet network molecules. The results suggest the magma-degassing mechanism of the formation of CO2 gas pools in the Shengli oilfield. 相似文献
59.
1981年以来对察尔汗盐湖三次渗漏试验结果表明,盐田渗漏是盐田土层与外界条件综合作用的结果,在盐田建设和生产管理过程中,应结合不同地点的土层特性、工程地质条件和其它有关条件,采取不同的处理措施。 相似文献
60.
热带西太平洋暖池和副热带高压之间的关系 总被引:14,自引:1,他引:13
文中研究了热带西太平洋暖池和西太平洋副热带高压的季节性变化和年际变化关系。结果表明,西太平洋暖池面积和副热带高压面积指数季节变化趋势基本一致,暖池中心的纬向移动与副热带高压西伸脊点相反,而经向移动和500hPa副热带高压脊平均位置的南北季节性变化非常一致。西太平洋副热带高压的年际变化落后暖池大约3个月左右,用暖池28℃或29℃面积指数可以很好地预测出当年6,7,8三个月西太平洋副热带高压的面积指数。 相似文献