1947～2007年上海中心城区居住空间分异变化——基于居住用地类型视角

采用4种分异度测度模型,在街坊尺度和乡镇尺度下,对上海中心城区1947～2007年11个时相的各类居住用地空间分异程度进行计算。发现1949年后各类居住用地分异度呈现不同的波动过程。不同时期居住用地总体分异程度的计算表明,1949年前空间分异严重,计划经济时期有所降低,转型期则又明显上升。不同时期居住用地等级高低与其分异度大小呈现不同的结构特征,1949年前高等级居住用地分异度高、中低等级居住用地分异度较低,形成"一高两低"结构;计划经济时期则是居住用地等级越高,分异度越大的"正相关"结构;90年代后则是最高和最低等级的居住用地分异度高,而中等居住用地分异度最低的"V"型结构。不同时期居住用地空间分异结构特征间的演进,直接原因是新式住宅的建设和旧城的改造,深层次原因则是土地使用制度的变迁和城市空间组织模式的转变。     

Temporal Variations of the Spring Persistent Rains and South China Sea Sub-high and Their Correlations to the Circulation and Precipitation of the East Asian Summer Monsoon

National Meteorological Information Center （NMIC） rainfall data and NCEP/NCAR daily circulation reanalysis data are employed to establish the onset-pentad time index of the spring persistent rains （SPR） and the decay-pentad time index of the South China Sea （SCS） sub-high. These indexes are used to study the relationship between the factors in SPR period and their relations to the circulation and precipitation of the East Asian summer monsoon （EASM）. Results show that, the summer rainfall over southeastern China decreases when SPR onset is late. For then EASM strengthens and the cyclonic circulation around the Tibetan Plateau （TP） strengthens, which makes abnormal anti-cyclonic circulation （cyclonic convergent circulation weakens） appear over southeastern China. When the decay of SCS sub-high delays, abnormal flood prevails over the middle and lower reaches of the Yangtze River （MLYR） and to the south. That is mainly caused by EASM weakening while SCS sub-high strengthening, then the abnormal southwesterly over South China and the abnormal northerlies of anti-cyclonic circulation around the TP converge over the Yangtze Valley. The two indexes have high correlations with multivariate ENSO index （MEI） in March, indicating that the climate abnormity in East Asia is related to global climate abnormity tightly. The two time indexes are independent of each other, which is favorable for the prediction of the anomalies of the circulation and precipitation of EASM. From this point of view, we must take the global climate background into account when we analyze and predict the East Asian summer circulation and precipitation.     

气象因素异常指数对我国典型工业产业的影响研究

为了研究气象因素对我国典型工业产业的影响状况,通过整理1999-2006年每日4个时次的气象因素如气温、风速、相对湿度、气压和降水等数据,构造了气象异常值和异常度指数,并收集了同时期我国6个典型的工业产业的销售收入、资本投入和劳动力投入等月份数据,利用科布-道格拉斯(Cobb-Douglas)生产函数模型,分析了这些气象异常指数对我国典型工业产业的影响及弹性,做了对比分析,得到了有启示意义的结论,最后指出了研究的不足及未来进一步研究的方向.     

1961-200年中国各季降水趋势变化

Trends in six indices of precipitation in China for seasons during 1961-2007 were analyzed based on daily observations at 587 stations. The trends were estimated by using Sen＇s method with Mann-Kendall＇s test for quantifying the significance. The geographical patterns of trends in the seasonal indices of extremes were similar to those of total precipitation. For winter, both total and extreme precipitation increased over nearly all of China, except for a small part of northern China. Increasing trends in extreme precipitation also occurred at many stations in southwestern China for spring and the midlower reaches of the Yangtze River and southern China for summer. For autumn, precipitation decreased in eastern China, with an increasing length of maximum dry spell, implying a drying tendency for the post-rainy season. Wetting trends have prevailed in most of western China for all seasons. The well-known ＇flood in the south and drought in the north＇ trend exists in eastern China for summer, while a nearly opposite trend pattern exist for spring.     

亚太季风各子系统的准两年变化特征及其比较

亚太季风各子系统（南亚季风、南海季风、西北太平洋季风和东亚副热带季风）都具有显著的准两年变化周期,利用4个季风指数研究它们准两年模态振幅的演变和相关的环流变化。结果表明,亚太季风各子系统的准两年模态有明显的年代际变化,并不是一直有效地影响季风区。与亚太季风各子系统准两年变化相关的海温异常,低层风场也有不同的分布特点和演变特征。     

Textural and geochemical characteristics of the Ajali Sandstone,Anambra Basin,SE Nigeria: Implication for its provenance

This study presents the mineralogical, textural and geochemical characteristics of the regional Maastrichtian Ajali Sandstone in Anambra Basin, SE Nigeria. The intent is to highlight possible constraints on the chemical weathering conditions of the source materials on one hand, and to infer the provenance on the other hand. The investigation approach involved field studies and collection of samples from 12 different outcrop locations, followed by laboratory studies involving grain-size analysis (GSA), major and trace elements analyses using the X-ray fluorescence (XRF) method as well as thin section petrography. Field studies show that the sandstones are friable at all locations and range in color from white in freshly cut stone, to reddish brown on weathering. In addition, the sandstone units are cross-bedded and show graded bedding exemplified by fining upward sequence. Textural examination indicates that the sandstones range from fine to medium sands, constituting about 76 to 99% sand fraction, with graphic mean grain size of 0.23 to 0.53 mm. Standard deviation (sorting) ranges from 0.56 to 1.24 Ø and implies moderately well sorted sediments. Inferred from the textural indices, the depo-environmental discrimination of the Ajali Sandstone revealed a fluvial/river system-dominated sedimentary process. The sandstones are quartz arenite with quartz greater than 90% and less than 5% K-feldspar which indicate a predominant basement source as also revealed by the heavy mineral assemblages. In addition, major elemental oxides shows SiO₂ content greater than 96% for the fresh Ajali Sandstone samples with extreme depletion of mobile oxides such as Na₂O, CaO and the ferromagnesian minerals through weathering and sedimentary processes. Provenance and tectonic setting discrimination using geochemical data and compositional maturity revealed typical felsic igneous-dominated cratonic environment while inter-elemental ratios (such as Zr/Cr, Y/Ni, Th/Sc, La/Sc and La/Co) and ternary plots (e.g. Th–Sc–Zr; La-Th–Sc and Th-Co-Zr) reflect passive continental margin setting for the Ajali Sandstone. Consequently, the source area is constrained to the Precambrian basement rock units of Adamawa-Oban massif areas to the east of the Anambra Basin and the adjacent Abakaliki Anticlinorium.     

上海市近岸海域表层沉积物类型与元素丰度相关关系特征

通过上海市近岸海域多目标区域地球化学调查,共采集947件表层沉积物样品,分析测试了52种化学元素以及pH值和有机碳等指标。总结了该区域表层沉积物及深层沉积物类型和分布特征,沉积物类型主要为细砂、粉砂质砂、砂质粉砂、粉砂、粘土质粉砂,其中粘土质粉砂分布最为广泛。元素含量与砂含量呈正相关的元素主要为SiO2、Sr、Na2O等。其它指标大都与粘土含量呈正相关关系。     

某些南极陨石元素的丰度特征

用中子活化分析测定了７个南极球粒陨石的主量和微量元素含量，讨论了这些陨石的元素丰度分布特征、南极陨石和非南极陨石的元素丰度差异，并划分了这７个南极陨石的化学群：Ｙ７９１７１７（Ｃ３），Ｙ７４１９３（Ｈ５），ＡＬＨ７６００６（Ｈ６），ＡＬＨ７７２１４（Ｌ３），Ｙ７５２７１（Ｌ５），ＡＬＨ７６００１（Ｌ６），ＡＬＨ７６００９（Ｌ６）陨石。     

吉林省四平市山门银矿成矿地质条件分析

本文对吉林省四平市山门银矿的成矿地质条件从地层、构造、岩浆活动、冷水蚀变等四个方面进行了分析。结果认为，上述四个方面为该矿的成矿物质来源、成矿物质的富集沉淀、导矿和储矿等提供了必备的物理条件和化学条件。