南泥湾湿地生态变迁研究

南泥湾是我国陕北的一片重要湿地,曾为中国革命的生存和发展提供了重要保障,在抗战时期垦殖而至今未被科学认知。根据史料记载以及人物传记,基于南泥湾湿地的科学认定,分析了南泥湾湿地的生态变迁,明确提出恢复南泥湾湿地,为陕北的好江南建设提供一定的科学支撑,为南泥湾湿地的恢复与部分重建提供前期基础。理想完美的南泥湾生态系统应当是湿地、森林、农田、草地的综合体,应当是陕北黄土高原的一块绿洲。     

An Interdecad l Change of Summer Atmospheric Circulation over Asian Mid-High Latitudes and Associated Effects

The atmospheric circulation over the mid-high latitudes in Asia has an important influence on regional climate, yet its long-term variation has not been fully explored. The main task of this study is to reveal the interdecadal variation features of summer atmospheric circulation over Asian mid-high latitudes in recent decades. The results show that the atmospheric circulation over mid-high latitudes of Asia has stronger interdecadal fluctuations than that over low latitudes and one significant change center appears near Lake Baikal. It is found that the atmospheric circulation near Lake Baikal has a significant interdecadal change around 1996 and a deep anomalous anticyclonic circulation has been controlling this region since then, which contributes to the significant increase in the surface temperature near Lake Baikal since 1997 and makes the region a remarkable warming center in Asia in recent 40 years. During 1997-2015, the pattern of less precipitation in the north and more precipitation in the south of east China is closely related to the anomalous anticyclonic circulation near Lake Baikal. Especially, this anomalous circulation near Lake Baikal has been found to contribute to the obvious interdecadal decrease of the precipitation in northeast China and north China near 1997. The sea surface temperature (SST) of northwestern Atlantic is an important influence factor to the interdecadal change in the atmospheric circulation near Lake Baikal around 1996.     

Comparison of the Structure and Evolution of Intraseasonal Oscillations Before and After Onset of the Asian Summer Monsoon

High-resolution satellite-derived data and NCEP-NCAR reanalysis data are used to investigate intraseasonal oscillations （ISO） over the tropical Indian Ocean.A composite evolution of the ISO life cycle is constructed,including the initiation,development,and propagation of rainfall anomalies over the tropical Indian Ocean.The characteristics of ISO over the tropical Indian Ocean are profoundly different before and after the onset of the Indian summer monsoon.Positive precipitation anomalies before monsoon onset appear one phase earlier than those after monsoon onset.Before monsoon onset,precipitation anomalies associated with ISO first initiate in the western tropical Indian Ocean and then propagate eastward along the equator.After monsoon onset,convective anomalies propagate northward over the Indian summer monsoon region after an initial eastward propagation over the equatorial Indian Ocean.Surface wind convergence and air-sea interaction play critical roles in initiating each new cycle of ISO convection.     

亚洲区域海—陆—气相互作用对全球和亚洲气候变化的作用研究进展

围绕全球变化研究国家重大研究计划项目“亚洲区域海—陆—气相互作用机理及其在全球变化中的作用”预定的总体研究内容和科学目标,项目执行两年多以来,取得了一系列阶段性科研成果.关于气候动力学方面,项目揭示了热带印度洋—西太平洋暖池的海温变化是全球热带气候年代际变化的重要驱动力,是全球尺度副热带干旱的重要调控器;发现热带东太平洋海温存在冷舌模态,它是一个海气耦合模态,阐明在全球变暖背景下其对ENSO型态变异的作用及影响东亚气候的机理;揭示了青藏高原热力强迫的异常特征及其气候效应;提出了水平非均匀基流中行星波传播的理论,研究了其在不同东亚夏季风背景下的传播特征.关于气候预测方法方面,提出了若干有物理基础的气候预测方法,如尺度分离的降尺度预测新方法、基于北大西洋涛动(NAO)-ENSO的东亚夏季风预测模型、基于南半球环状模的东亚气候预测模型等,为业务部门提供了重要参考.关于观测方面,项目在亚洲区域海气补充观测和海洋资料同化方面也取得突出进展,成功进行了南海18°N断面海洋综合观测,为形成我国第一条南海断面长期海气观测打下了基础.在国际合作方面,项目还继续推动和领导了“亚洲季风年”(AMY2007-2012)与“东亚气候模拟”国际计划,提升了我国在该领域的国际地位.     

HD 12661行星系统构形的形成与稳定性

最近的多普勒观测表明恒星HD 12661周围存在两颗中等偏心率轨道上运行的行星,内行星的最小质量为2．3木星质量,轨道周期为263．6天;外行星的最小质量为1．57木星质量,轨道周期为1444．5天．该系统的稳定性要求两颗行星处在平运动轨道共振．用数值方法研究了该系统形成初期在恒星气体盘作用下的轨道迁移与稳定性,计算了行星在迁移中被平运动共振俘获的概率．发现这两颗行星目前很可能正处在11:2平运动共振边缘,且运动是混沌的,从而澄清了关于系统目前构形的不同说法,并且很可能在系统形成后行星迁移到目前构形时,气体盘几乎消失了．     

Concentrations and Distribution of Trace Metals of PM_(10) and TSP Particles Collected in the Qingdao Area

Aerosol samples of PM10 (particulate matter with aerodynamic diameters less than 10μm) and TSP (total suspended particles) were simultaneously collected from April 2001 to March 2002 at the top of Mount Baguan on the downtown campus of Ocean University of China, Qingdao, China. The concentrations of Al, Fe, Mn, Cu, Pb and Zn were determined by means of inductively coupled plasma atomic emission spectrometry (ICP-AES). The monthly variability of the mass concentrations of aerosol particles and the concentrations of trace metals are presented and discussed. The distribution pattern of these metals in PM10 and TSP is also discussed. During the observation period, the mass concentration of PM10 at this site ranged from 13.80 to 306.42μgm-3 , while that of TSP ranged from 31.02 to 568.82μgm-3. Both PM10 and TSP reached their highest concentrations in springtime, while the lowest values occurred in summertime. The concentrations of crustal metals followed the same variation pattern, while those of anthropo     

造山带金矿研究现状与存在的问题

造山带金矿是当前矿床学和大地构造学研究热点,Groves等(1998)、Goldfarb等(2001)基于太古"地壳连续模式"(Groves,1993)的研究工作以涉及资料量大、应用成果新、考虑地质因素多而居于这一领域前沿.但是,目前众多研究对前寒武地质与显生宙地质的宏观差异、世界金矿一些总体规律及若干具体大地构造背景等尚认识不足.显生宙缺乏太古代大规模火成活动,已知金矿中很少同变质深成型(hypozonal),以浅变质岩为围岩的金矿区中没有相当的中-深变质岩为围岩的金矿."太古绿岩带"金矿区同样也缺乏浅变质岩为围岩的金矿.华北地块周边金矿主要形成在侏罗-白垩纪,明显晚于大兴安岭造山带和秦岭-大别山造山带,而与欧亚陆缘近南北向燕山期岩浆弧有关.距俯冲带较远、缺乏蛇绿混杂岩与大规模变质作用、发育大量中-新生代盆地及广泛地壳减薄等表明,中国东部与北美科迪勒拉(Cordillera)造山带晚中生代地质存在宏观差异,燕山期岩浆弧可能形成于一个以伸展为主导的环境,大量以花岗岩为围岩或相对太古变质围岩后生成因金矿及其成矿的大地构造背景值得深入研究,弄清各类显生宙金矿与造山带的关系是推进造山带金矿研究的关键.     

中等距离GPS相位平滑伪距差分动态定位精度的测定

GPS相位平滑伪距差分动态定位可用于精度要求较高的水深测量、勘界测量以及土地调查测量等场合。在应用前需对其所能达到的定位精度进行认真的测定,着重对事后相位平滑伪距差分模式下的单频GPS接收机定位精度进行测定,测定结果表明30 km之内单频GPS接收机事后相位平滑伪距差分动态定位点位中误差小于0.8 m。此研究成果已应用于国土资源调查中。     

4D一体化多媒体电子地图集理论方法和技术研究与开发--以《云南省生态环境多媒体电子地图集》为例

本文首先研究了4D数据一体化多媒体电子地图集的理论和信息机理,包括4D数据在电子地图集中的集成、融合和应用的信息机理,多源多类信息交互认知和传输机理,4D信息的查询、分析、模拟、调控和表达的信息机理,以及4D数据一体化电子地图集的理论框架。其次,文章深入研究和解决了建立4D一体化多媒体电子地图集过程中的诸多技术方法问题,例如多源多类数据的集成和融合、基于主导数据库的多重表达、多媒体地图动画、基于4D数据的信息分析和量算、生态环境信息动态仿真和虚拟表达等。在论文第三部分,文章介绍了作者研发的《云南省生态环境多媒体电子地图集》成果,包括其结构、功能、内容、超媒体链接等方面的设计,查询功能和分析量算功能的开发,以及本电子地图集的分析应用成果。     

GPS精密钟差内插方法研究

GPS钟差的计算,可以通过精密星历内插所得。将IGS提供的15min精密星历内插到5min,其中分别用拉格朗日多项式、切比雪夫多项式法来进行内插,根据两种插值多项式分别比较分析在不同阶数情况下内插的精度。详细介绍了拉格朗日多项式、切比雪夫多项式插值法的基本原理,通过算例得出了拉格朗日与切比雪夫的拟合精度都可以满足精密定位需要,且切比雪夫插值的精度更高。