Periods of rapid environmental change around 12 500 and 10 000 years B.P., as recorded in Swiss lake deposits

In the sediment of three Swiss lakes at a range of altitude from 514 to 2017 m, the Bölling and the Preboreal are recognized as two periods of rapid biotic changes. The main reason is rapid climatic change that triggered shifts in different groups of aquatic and terrestrial organisms. Although these groups would be expected to have very different response times, e.g., to increasing summer temperature, their assemblages responded with surprizing synchroneity. For extracting climatic signals from stratigraphies, the quickly responsive indicators like oxygen isotopes or beetles are useful. For understanding ecological dynamics under a changing climate, the comparison of biota with various response time are important.This is the sixth of a series of papers to be published by this journal that was presented in the paleolimnology sessions organized by R. B. Davis and H. Löffler for the XIIth Congress of the International Union for Quaternary Research (INQUA), which took place in Ottawa, Canada in August 1987. Drs. Davis and Löffler are serving as guest editors of this series.     

高喜马拉雅地区聂拉木花岗岩快速抬升的裂变径迹证据

笔者对西藏高喜马拉雅地区聂拉木花岗岩样品进行了磷灰石裂变径迹分析。聂拉木淡色花岗岩4个不同高程(395～4200m)的裂变径迹年龄范围为3.79±0.34～8.17±0.47Ma,混合花岗岩4个不同高程(3260～3720m)的裂变径迹年龄范围为0.85±0.09～1.71±0.34Ma。结合已有的热年代学资料,提出整个高喜马拉雅造山带在上新世—第四纪时为快速抬升期。     

Growing Threat of Rapidly-Intensifying Tropical Cyclones in East Asia

This study examines the long-term change in the threat of landfalling tropical cyclones(TCs) in East Asia over the period 1975–2020 with a focus on rapidly intensifying(RI) TCs. The increase in the annual number of RI-TCs over the western North Pacific and the northwestward shift of their genesis location lead to an increasing trend in the annual number of landfalling RI-TCs along the coast of East Asia. The annual power dissipation index(PDI), a measure of the destructive potential of RI-TCs at landfall, also shows a significant increasing trend due to increases in the annual frequency and mean landfall intensity of landfalling RI-TCs. The increase in mean landfall intensity is related to a higher lifetime maximum intensity(LMI) and the LMI location of the landfalling RI-TCs being closer to the coast. The increase in the annual PDI of East Asia is mainly associated with landfalling TCs in the southern(the Philippines, South China, and Vietnam) and northern parts(Japan and the Korean Peninsula) of East Asia due to long-term changes in vertical wind shear and TC heat potential. The former leads to a northwestward shift of favorable environments for TC genesis and intensification, resulting in the northwestward shift in the genesis, RI, and LMI locations of RI-TCs. The latter provides more heat energy from the ocean for TC intensification, increasing its chances to undergo RI.     

SUSTAINABLE URBAN-RURAL RELATION IN RAPID URBANIZATION AREAS——Case of Transformation of “Urban Village” in Guangzhou

Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. However, most of these studies started mainly from the standpoint of the city govemment, drumming for the land- scape-oriented urbanization, namely pulling-down the urban village and constructing the splendid residence or business buildings. The article maintains that the most important thing the city government should do is to pay much attention to the sustainable living of urban villagers, who would lose their main income source, namely, the collective dividend and the family housing rent. The single method of compensation has been proved to be harmful to the villagers＇ community, in which some young villagers relying on rent were no longer to do anything but stay at home. On the other hand, considering the floating population has become the main stream of renters in urban villages, the emergence of urban villages was inevitable and would continue to exist in a long time under the socio-economic transition in urban China and globalization. Based on the analysis above, the transformation of urban village should take more concerns on the housing demands of floating population besides compensation for local villagers. Meanwhile, it is necessary to avoid the “landscape-oriented urbanization” without the “peasant-to-citizen” transformation.     

Rapid Exhumation in the Alpine Belt of the Betic-Rif (W Mediterranean): Tectonic Extrusion

—Extreme cooling rates (500 °C/m.y.) during the late stage, 22–18 Ma, orogenic evolution of the Alpine Betic-Rif belt are suggested to result from rapid exhumation caused by tectonic extrusion and concomitant extensional tectonics. The extrusional/extensional tectonic setting is controlled by the SW-NE trending break-off scar left in the lithosphere of the Alborán Sea and SE Spain after detachment of a lithospheric slab. The extruded material represents the collisional crustal nappe pile (together with fragments of underlying mantle, such as the Ronda peridotites) and the cause of the extrusion is the thermal softening within the crustal section during and after collision. The extrusion/extension took place under the influence of a NW-SE directed compressive regime, perpendicular to the collisional belt. At the same time the sub-lithospheric mantle still showed the E-W compressive regime of the collisional stage. The Alpine tectono-metamorphic evolution of the Betic-Rif belt in the W Mediterranean thus comprises two main stages: (1) continental collision with formation of primary nappes and high-pressure metamorphic parageneses, (2) tectonic extrusion with vertically directed tectonics (high pressure, very rapid decompression) and extensional tectonics with roughly horizontal, lateral transport and final emplacement of the extruded mélange in the form of a stack of detachment sheets (low pressure, very rapid cooling). This model for the Betic-Rif may offer important constraints to all rapidly exhumed convergent terranes.     

海水BOD快速测量技术研究

本文在分析淡水BOD快速测量技术基础上，对快速测量方法中：生物膜光纤传感器法、微生物膜电极法和生物反应器法进行了比较，生物反应器法具有：直接从水样中培养复合生物菌群；菌群的活性由系统自动调节外部条件来保证等特点，在培养出耐盐微生物菌群和进一步提高仪器检测灵敏度的条件下，可以应用于海水BOD快速测量。     

Kinetic Energy Budgets during the Rapid Intensification of Typhoon Rammasun (2014)

In this study, Typhoon Rammasun(2014) was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI). Budget analyses revealed that in the inner area of the typhoon,the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere. The increase in the symmetric rotational kinetic e...     

2006号台风“米克拉”近海急剧增强诊断分析

利用ERA-5再分析资料、日本葵花8号卫星黑体亮温资料以及中国气象局上海台风研究所台风最佳路径集资料,对2020年第6号台风“米克拉”（2006）近海强度急剧增强进行诊断分析。（1） 比常年偏暖的29～30 ℃的南海东部海温是“米克拉”急剧增强的有利下垫面条件;200 hPa加强东移的南亚高压、500 hPa加强西伸的副高、低层加强的偏南-西南急流是主要影响系统;相对比深层和高层大气,持续低于4 m/s的低层大气垂直风切是重要因子。（2） “米克拉”的增强主要体现在对流层低层动能的不断增强,在台风急剧增强过程中,中低层的气旋性涡度、低层辐合强度、中高层辐散强度以及上升运动均明显加强;对流层中高层动能在台风急剧增强前的减小可能与增强的高空出流相关。（3） 在“米克拉”急剧增强前,深对流云系强度不断增强,但覆盖面积变化不大;在急剧增强阶段,深对流云系组织的更加紧实集中,覆盖面积明显增大。     

手持式消光光度计的研制及用于掺杂牛奶的现场快速检测

自行设计新型消光池,研制了一种廉价的手持式消光光度计,并在此基础上建立了掺杂牛奶的现场检测方法。实验结果表明,所建立的方法无需对牛奶进行复杂处理,可对常见掺杂(如搀水、米汤、奶粉、豆浆、尿素等)牛奶和含重金属离子汞的牛奶,进行现场检测。由于采用新型消光池,有效地减小了蛋白质粒子因重力沉降所带来的误差,能够成功区分同密度劣质牛奶。该方法灵敏度高,对掺水牛奶的检出限低于2%,对重金属(如汞)的检出限为0.005μg/g。单个样品测定时间不到2 min,适合于牛奶品质的现场快速检测。     

基于VDRAS的快速更新雷达四维变分分析系统

基于雷达资料快速更新四维变分同化 (RR4DVar) 技术和三维数值云模式,初步研发了一个针对对流尺度数值模拟的快速更新雷达四维变分分析系统。系统通过对京津冀6部多普勒天气雷达资料进行RR4DVar同化,并融合5 min自动气象站观测和中尺度数值模式结果,可快速分析得到12~18 min更新的低层大气三维动力、热力场的对流尺度结构特征。针对2009年7月22日发生在京津冀的一次强风暴个例,通过一系列敏感性试验,并利用局地加密资料进行检验对比,表明有效的雷达资料RR4DVar同化及自动气象站和中尺度模式资料融合方案、恰当的中尺度背景场设置和动力约束方法是获得合理结果的关键。研究也表明:恰当的系统配置能够模拟出与对流生消发展密切相关的近风暴环境特征,包括低层入流、垂直风切变、低层辐合上升和暖舌等,以及风暴自身形成的冷池、出流等与风暴演变密切相关的对流尺度结构。