A Review of the Tetrapod Track Record in China,with Special Reference to Type Ichnospecies:Implications for Ichnotaxonomy and Paleobiology

<正>"Splitting" and "lumping" are perpetual problems in vertebrate,especially dinosaur, ichnotaxonomy.Chinese dinosaur ichnotaxonomy,which began in 1940,provides a series of interesting case studies,highlighting the dual problems of historical and dubious ichnotaxonomy. Chinese Mesozoic tetrapod track types have been placed into 63 ichnospecies(one Triassic,28 Jurassic,and 34 Cretaceous),exclusive of other,non-type ichnospecies or ichnotaxa identified from China.Fifty-two(～83%) of these 63 tetrapod ichnospecies were placed in monospecific ichnogenera. At the ichnogenus level,we prune—either by recognizing nomina dubia or by synonymy—17 from the list of 53 dinosaurian ichnogenera(a 32%reduction),leaving 36 ichnotaxa that we consider valid. Most of the cuts affect Jurassic theropod ichnotaxa,which are reduced from 23 to only nine because most ichnogenera are subjective junior synonyms of Grallator and Eubrontes.Fewer Chinese Cretaceous ichnotaxa(only six of 21 ichnogenera) are obvious nomina dubia or subjective synonyms, suggesting greater east Asian endemism during this time.Because ichnospecies differences are subtle, we provisionally retain ichnospecies as valid pending detailed comparative analyses of congeneric ichnospecies.This synthesis is long overdue and is necessary to address problems of historical and provincial ichnotaxonomy,which severely hamper comparisons of tetrapod ichnofaunas in space and time.     

地球早期地幔的冷凝结晶始于核幔边界或下地幔

JGR(Journal of Geophysical Research:Solid Earth)于2012年10月12日,发表了题为"Multi-technique equation of state for Fe2SiO4melt and the density of Fe-bearing silicate melts from 0to 161GPa"的文章指出,地球早期地幔的冷凝结晶可能始于核幔边界或下地幔。地球形成初期,地幔可能是一个整体熔融或局部熔融的巨大岩浆洋,其深度直达核幔边界。尽管目前地幔的物质大多都是固     

Geotechnical problems of construction on permafrost in Mongolia

Permafrost is found on 63%of the territory of Mongolia. This paper provides evidence that the main influences on per-mafrost formation are meso and micro factors of climate and geographical location. R...     

Parkes脉冲星数据库使用方法

Parkes脉冲星数据库目前已经收集了从1991年至今由Parkes望远镜观测的165755个数据文件。数据文件及其存取方法遵循虚拟天文台协议。介绍了脉冲星数据库的使用方法,以及使用在线界面进行数据获取的例子。     

渭河流域沉积物碎屑锆石U-Pb年龄物源示踪

渭河盆地是秦岭山前新生代陆内断陷盆地,接受大量秦岭造山带的沉积。建立渭河盆地沉积物物源示踪体系,对了解渭河盆地和秦岭的盆山耦合关系及其周缘构造-沉积演化均具有重要的意义。对渭河流域干流及主要支流沉积物进行碎屑锆石U-Pb年龄测试。结果表明:渭河干流沉积物碎屑锆石主要呈现五组年龄区间,分别为100~300、300~500、700~1000、1700~2000和2100~2500 Ma,其中以100~300 Ma和300~500 Ma的锆石为主,判别渭河干流沉积物主要来自北秦岭造山带。渭河上游与中下游沉积物在1700~2000 Ma和2100~2500 Ma的年龄组成存在差异,主要与上游出露的元古代岩体相关。渭河支流沉积物碎屑锆石年龄分布存在显著差异。泾河和洛河流经黄土高原,沉积物碎屑锆石U-Pb年龄与黄土高原相似,主要表现为200~300、400~500、800~1100、1800~2000和2400~2550 Ma五组年龄;灞河沉积物继承了北秦岭造山带的特征。通过对渭河流域沉积物的物源分析可知:泾河对渭河干流沉积物贡献较大,灞河对渭河干流沉积物贡献较小,洛河对渭河干流沉积物有一定贡献。渭河汇入黄河前后,黄河沉积物碎屑锆石年龄峰分布及各年龄区间锆石含量比例有明显变化,反映渭河对黄河沉积物有较大影响。     

祁连山地区当地居民对雪豹(Panthera uncia)野生猎物物种的态度及其影响因素（英文）

作为全球生态环境保护问题之一的人兽冲突(HWC)正受到越来越多的关注。了解人兽冲突产生的原因对于预防和缓解人兽冲突十分重要。在中国的许多地区,大量的人口和当地的经济发展加剧了当地居民与捕食动物以及猎物之间的冲突。本研究通过对甘肃省祁连山国家级自然保护区内8个村庄46户当地牧民的访谈,调查评估了祁连山地区当地居民对岩羊(Pseudaois nayaur,Hodgson,1833)、白唇鹿(Carvus albirostris,Przewalski,1883)、马鹿(Cervus elaphus,Linnaeus,1758)和喜马拉雅旱獭(Marmota himalayana Hodgson,1841)的态度。我们调查了当地基于草原畜牧业的三种生态修复政策(禁牧、可持续放牧和种草)对当地居民的影响,研究了这些政策对当地居民对野生动物态度产生的影响。结果表明,整体上当地牧民对野生动物持中性态度,但对岩羊表现出消极态度。混合效应线性模型的结果表明,不同村庄的牧民对特定物种的态度不同,社会经济因素不能很好地解释这一结果。此外,我们发现,尽管有时当地居民对一些政策的实施持消极看法,禁牧和其它政策的实施和当地牧民对野生动物的积极态度依然呈正相关。这一发现表明,我们通常认识的威胁野生动物生存的因素与实际的威胁因素之间存在潜在偏差。同时,我们发现当地居民报道的家畜死亡主要是可预防性疾病造成的,因此,对当地流行性疫源疫病的防控可能会对当地居民的野生动物态度产生积极影响。     

Line-source multi-tracer test for assessing high groundwater velocity

Segmented line-source multi-tracer injection is suggested as an effective method for assessing groundwater velocities and flow directions in subsurfaces characterized by high water flux. Modifying the common techniques of injecting a tracer into a well became necessary after point-source natural and forced gradient tracer tests ended with no reliable information on the local groundwater flow. The tracer's line-source increases the likelihood of success of the test and could provide additional information regarding the lateral heterogeneity of the aquifer. In a field experiment conducted in the northwestern part on the Dead Sea coast, tracers were injected into an 8-m-long line injection system perpendicular to the assumed flow direction. The injection system was divided into four separate segments with four different tracers. An array of five boreholes located within a 10 × 10 m area downstream was used for monitoring the tracers' transport. Two dye tracers (uranine and Na naphthionate) were injected in a long pulse of several hours into two of the injection pipe segments. Two other tracers (Rhenium oxide and Gd-DTPA) were instantaneously injected into the other two segments. The tracers were detected 0.7 to 2.3 h after injection in four of the five observation wells, located 2.3 to 10 m away from the injection system. The groundwater velocity was determined to be ～80 to 170 m/d, based on the recoveries of the tracers. The groundwater flow direction was derived based on the arrival of the tracers and was found to be quite consistent with the apparent direction of the hydraulic gradient.     

对J C Savage关于“沿圣安德烈斯断层蠕变部分的无震滑动和垂直断层应变”所作评论的回复

太平洋板块与希拉内华达大峡谷微板块间的相对运动大多数是通过沿圣安德烈斯断层的走向滑动来调整的。在圣安德烈斯断层中部（CSAF）,沿走向的滑动近于以无震断层蠕变的形式发生（Thatcher,1979;Titus等,2006;Rolandone等,2008;Ryder and Burgmann,2008）。