地球磁场偶极子和非偶极子分量变化特征及其相关的地球深部过程

通过分析１９００年以来每５ａ地球磁场各阶球谐系数的相关系数发现,地球磁场偶极子分量的ρ值在１９０５-１９７０年基本保持不变,１９７０-１９８５年下降,１９８５-１９９５年又上升,呈Ｖ字型变化。而非偶极子分量的　值则具有周期性变化,在１９１５年、１９４５年和１９８０年出现峰值,在１９３５年和１９６５年则处于低谷,变化周期约为３０ａ。通过分析地球磁场非偶极子分量　值周期变化与日长周期变化的相关性,得出两点新的认识：１．非偶极子分量的周期性变化与核幔边界耦合过程相关,而偶极子分量的变化对应外核的深部过程;２．外核顶部流体具有周期性的变化,其变化周期与日长及非偶极子分量的变化周期一致。     

中国土壤环境中Th元素与癌症的关系

利用土壤环境中钍元素７６７个数据,癌死亡调查资料７８７０８０例,研究了胃癌、食管癌、肝癌、宫颈癌、肺癌、大肠癌、白血病、鼻咽癌、乳腺癌死亡率与人群生存区土壤环境中钍元素的关系。结果表明,胃癌、食管癌、宫颈癌、肺癌、鼻咽癌死亡率与钍元素有相关性,等级相关系数分别为－０．３８５７,－０．３２５６,－０．４５４２,－０．３８２８,０．６１５３。     

南黄海浮游植物与水色透明度之间相关关系的研究

本文根据 １９９５ 年 ９ 月在南黄海获取的资料,分析和讨论了该水域浮游植物现存量（叶绿素 ａ （ Ｃ Ｈ ））、初级生产力（ Ｐ Ｐ） 和海水光学参数（透明度（ Ｓ Ｔ））、水色（ Ｗ Ｃ）） 之间的相关关系。分析结果表明,夏末秋初南黄海 Ｃ Ｈ 与 Ｐ Ｐ, Ｃ Ｈ 与 Ｗ Ｃ 和 Ｐ Ｐ 与 Ｗ Ｃ 以及悬浮物（ Ｓ Ｓ） 与 Ｗ Ｃ 之间均有良好的正相关关系。相关式分别为： Ｐ Ｐ ＝ ２２５１９ｌｎ（ Ｃ Ｈ ） ＋ ４８８９１ 或 Ｐ Ｐ ＝ ５ Ｅ－ ０５ Ｃ Ｈ １６４６４（ Ｒ２ ＝ ０７０３７）; Ｗ Ｃ ＝ ４０３ｌｎ（ Ｃ Ｈ ） ＋ ８９７６８ 或 Ｗ Ｃ ＝ ７１３０６ Ｃ Ｈ ０４７４７ （ Ｒ２ ＝０７９２１）; Ｃ Ｈ ＝ １５４３７ｌｎ（ Ｓ Ｓ） ＋ １３６４７ 或 Ｃ Ｈ ＝ ０７４９９ Ｓ Ｓ１２５２（ Ｒ２ ＝ ０７２２３）; Ｐ Ｐ ＝３３２８６ｌｎ Ｓ Ｓ＋ １５２２２ 或 Ｐ Ｐ ＝ ３３０２９ Ｓ Ｓ０５６９４ （ Ｒ２ ＝ ０５４７６）; Ｐ Ｐ ＝ ４２５８８ｌｎ（ Ｗ Ｃ） － ３７０７１或 Ｐ Ｐ ＝ ６６５１２ Ｗ Ｃ０８６６５（ Ｒ２ ＝ ０６７３１） 以 及 Ｓ Ｓ ＝ １４０１９ｌｎ（ Ｗ Ｃ） － １３３６３      

Correlation between abnormal trends in the spontaneous fields of tectonic plates and strong seismicities

Tectonic activities, electrical structures, and electromagnetic environments are major factors that affect the stability of spontaneous fields. The method of correlating regional synchronization contrasts(CRSC) can determine the reliability of multi-site data trends or shortimpending anomalies. From 2008 to 2013, there were three strong earthquake cluster periods in the North–South seismic belt that lasted for 8–12 months. By applying the CRSC method to analyze the spontaneous field E_(SP) at 25 sites of the region in the past 6 years, it was discovered that for each strong earthquake cluster period, the E_(SP) strength of credible anomalous trends was present at minimum 30%of the stations. In the southern section of the Tan-Lu fault zone, the E_(SP) at four main geoelectric field stations showed significant anomalous trends after June 2015, which could be associated with the major earthquakes of the East China Sea waters(MS7.2) in November 2015 and Japan's Kyushu island(MS7.3) in April 2016.     

地磁活动对气候要素影响的研究进展

地磁活动是太阳爆发现象引起地球近地空间磁场扰动的重要空间天气过程之一.地球磁场的变化具有多种时间尺度,其中从数十年到数世纪的长时间地磁场变化主要是由地核磁场引起的,而从数秒到数年的短时间地磁变化与太阳活动有关.近年来,越来越多的统计研究表明,地磁活动与太阳活动和地球气候变化之间存在着显著的相关性.地球磁场和地球大气系统的耦合现象驱动着人们探索地磁活动对地球天气和气候系统影响的研究.本文的目的就是综述国内外地磁变化对气候影响的研究进展,介绍我们最新的研究成果,探索地磁活动对气候要素的影响特征和可能机理过程,为深入研究地磁活动对地球天气和气候的影响提供基础和依据,以期对地磁活动和气候要素关系有进一步的认识.     

精河6.6级地震前精河水管仪、伸缩仪异常特征分析

2017年8月9日精河发生6.6级地震。本文首先利用相关、回归分析研究了气温对水管仪、伸缩仪的影响,并进行了干扰的定量剔除;其次,通过回归残差分析研究地震前水管仪、伸缩仪的异常特征,认为精河6.6级地震前存在3项异常:①2016年5月22日起,水管仪NS分量S倾幅度0.53";②2017年3月24日起,EW分量E倾幅度0.28";③2016年9月10日起,伸缩仪NS分量出现压缩现象。     

Evolutionary biogeography on Ophiocordyceps sinensis:An indicator of molecular phylogeny to geochronological and ecological exchanges

The fungus Ophiocordyceps sinensis is endemic to the vast region of the Qinghai-Tibetan plateau(QTP).The unique and complex geographical environmental conditions have led to the "sky island" distribution structure of O.sinensis.Due to limited and unbalanced sample collections,the previous data on O.sinensis regarding its genetic diversity and spatial structure have been deemed insufficient.In this study,we analyzed the diversity and phylogeographic structures of O.sinensis using internally transcribed spacer region(ITS) and 5-locus datasets by a large-scale sampling.A total of 111 haplotypes of ITS sequences were identified from 948 samples data of the fungus O.sinensis,with representing high genetic diversity,and 8 phylogenetic clades were recognized in O.sinensis.Both the southeastern Tibet and the northwestern Yunnan were the centers of genetic diversity and genetic differentiation of the fungus,and they were inferred as the glacial refugia in the Quaternary.Three distribution patterns were identified to correspond to the 8 clades,including but not limited to the coexistence of widely and specific local distributive structures.It also revealed that the differentiation pattern of O.sinensis did not fit for the isolation-by-distance model.The differentiation into the 8 clades occurred between 1.56 Myr and6.62 Myr.The ancestor of O.sinensis most likely originated in the late Miocene(6.62 Myr) in the northwestern Yunnan,and the Scene A-C of the Qinghai-Tibetan movements may have played an important role in the differentiation of O.sinensis during the late Miocene-Pliocene periods.Our current results provide a much clearer and detailed understanding of the genetic diversity and geographical spatial distribution of the endemic alpine fungus O.sinensis.It also revealed that the geochronology resulting from paleogeology could be cross-examined with biomolecular clock at a finer scale.     

气象条件对奶牛产奶量的影响及对策

在分析奶牛产奶量时间和空间分布的基础上,将乌兰浩特市全市产奶量和乌兰哈达奶牛场观测站产奶量与乌兰浩特市气象资料进行相关分析,确定了影响当地牛奶产量的关键气象因子和关键时期。结果表明,温度是当地春秋季节和冬季影响奶牛产奶量的主要限制因子,其次是气压和相对湿度,而降雨量和日照时数的影响不明显。     

A procedure for simulating synthetic accelerograms compatible with correlated and conditional probabilistic response spectra

The modeling of seismic load is a major topic that has to be addressed thoroughly in the framework of performance based seismic analysis and design. In this paper, a simple procedure for simulating artificial earthquake accelerograms matching the statistical distribution of response spectra, as given by median ground motion prediction equations, the standard deviation and correlation coefficients, is proposed. The approach follows the general ideas of the (natural) ground motion selection algorithms proposed by Baker [4] and Wang [43] but using simulated (artificial) “spectrum-compatible” accelerograms. This allows to simulate spectrum-compatible accelerograms featuring variability similar to the one of recorded accelerograms when the match of median and ±1 standard-deviation response spectra is imposed by the regulator. The procedure is illustrated by an application to the NGA ground motion data and models.     

合肥地震台地电阻率与气温、降水、地下水位关系的初步研究

经对地电阻率ρs观测值的分析研究,发现观测数据因受本身台址电性条件的限制,观测深度较浅,受降雨等气象因素的影响明显.运用合肥地电阻率北南、北西向2007-2013年观测资料月均值与温度、降水、地下水位进行相关分析,采用多元线性回归方法对地电阻率进行校正,以反映地电阻率的真实变化,达到提取地震异常的目的.