ENVIRONMENTAL CHANGES IN THE EASTERN CHINA DURING THE LATE PLEISTOCENE

The environmental changes during the Late Pleistocene were more obvious in the eastern China than in other areas at the same latitude, which either between northern and southern, or between land and sea of the eastern China were mostly non-synchronous. The transitional period prior to the last glaciation came about in the northern part of the eastern China about 115,000 yr. ago. The desert environments of the inland of the north China were developed both in the glacial maximum and in the warm interglacial period, but the loess accumulation mostly took place during the glacial period. The sand dunes and the periglacial solifluctions in the lower Changjiang (Yangtze) River region were formed during the last glacial period. The event of lowest surface temperature occurred at 98,000 yr. B.P. and 59,000 yr. B.P. in the northern part of the South China Sea but not during the full-glacial stage. The phenomena mentioned . above were the result of the following reasons that the paleo-environmental changes in the     

贺兰山群早元古代花岗岩的地质特征和岩石谱系单位划分

通过对呼鲁斯太幅和古拉本幅的１／５万区域地质调查工作，对该地区太古代贺兰山群中－高级变质岩中早元古代花岗岩进行了岩石谱系单位的划分和填图。在此基础上，从花岗岩的地质学、岩石学、岩石化学和地球化学等方面进行了较系统的详细研究，把早元古代花岗岩划分出７个单元，并将其中的５个单元归并为两个超单元。     

The Initiation of the "Little Ice Age" in Regions Round the North Atlantic

The "Little Ice Age" was the most recent period during which glaciers extended globally, their fronts oscillating about advanced positions. It is frequently taken as having started in the sixteenth or seventeenth century and ending somewhere between 1850 and 1890, but Porter (1981) pointed out that the "Little Ice Age" may 'have begun at least three centuries earlier in the North Atlantic region than is generally inferred'. The glacial fluctuations of the last millennium have been traced in the greatest detail in the Swiss Alps, where the "Little Ice Age" is now seen as starting with advances in the thirteenth century, and reaching an initial culmination in the fourteenth century. In the discussion here, evidence from Canada, Greenland, Iceland, Spitsbergen and Scandinavia is compared with that from Switzerland. Such comparisons have been facilitated by improved methods of calibrating radiocarbon dates to calendar dates and by increasing availability of evidence revealed during the current retreat phase. It is concluded that the "Little Ice Age" was initiated before the early fourteenth century in regions surrounding the North Atlantic.     

机载多光谱影像语义分割模型在农田防护林提取中的应用

农田防护林是农田生态系统的屏障,其健康状况的监测与评估在我国北方农田林网管理中尤为重要。本文以新疆生产建设兵团第三师51团为研究区,使用复合翼无人机CW-20搭载Micro MCA12 Snap多光谱相机获取农田防护林的多光谱影像,经辐射校正、裁剪等预处理,通过优选有效特征和模型比较,提出农田防护林提取的有效方法。首先,基于原始12波段,依据相关性系数矩阵和最佳指数因子（Optimum Index Factor,OIF）选取最优3波段和植被指数特征进行组合,构建8种农田防护林提取方案;然后,通过建立语义分割Deeplabv3+模型进行精度评价,得到最优3波段组合6（波长710 nm）、8（波长800 nm）、 11（波长900 nm）波段为最佳特征组合;最后,以最优3波段为基础,将Deeplabv3+模型与U-Net、ENVINet5模型进行对比分析。结果表明：Deeplabv3+模型能够更深层次的挖掘光谱中潜在的信息,相比其他模型,能够较好地处理正负样本不均衡问题,获得最高MIoU值85.54%,比U-Net、ENVINet5的MIoU值则分别高出21.21%、27.19%。该研究结果可为基于多光谱遥感影像的语义分割在农田防护林提取及健康状况监测的应用提供借鉴和参考。     

喜马拉雅山脉与我国东部中低山区冰蚀地貌对比研究

我国东部中低山区第四纪冰川的存在与否一直存在争议,但冰川必然对山体进行冰蚀作用形成冰蚀地貌。为了分析我国东部中低山区的山体地貌是否具有冰蚀特征,该文选取了现代冰川集中发育区-喜马拉雅山脉作为冰蚀地貌的研究对象,通过宏观分析,除了由缩口、三角脊、残弧组成的冰斗系统外,还发现冰蚀作用过程存在避谷、吞脊、切壁、穿梁等特殊习性。分析认为冰蚀过程主要受制于雪线高程、积雪高程与坡向坡角三方面因素的控制。以此为基础,对我国东部的江西庐山、山东蒙山、大兴安岭主峰黄岗梁三个地区的山体地貌进行对比分析,发现这些山区的山体地貌与喜马拉雅山脉的冰蚀地貌具有一致性。文章从冰蚀过程的角度确认了我国东部中低山区存在第四纪冰川的事实。     

秦汉简帛中不定数的表示形式及发展

不定数是称数法的一个重要组成部分,秦汉时期又是称数法剧烈发展变化的时期,出土材料的发掘整理又为这一研究提供了新的语料来源。对秦汉简帛中不定数的表示形式进行系统考察,发现秦汉时期表不定数的词增多,数词连用表不定数的形式更为丰富,出现了不定数表示的羡余形式。     

River rafting in mountainous regions of Uttarakhand: Impacts, suggested mitigation measures and sustainability

Uttarakhand state in India is well known for its mountainous ecosystems,traditional communities and a variety of ecotourism destinations.Among various tourism activities,River Rafting along the banks of the Ganges River has increased tremendously for two decades,and has had unprecedented impacts on the traditional communities and the bio-diversity.Therefore,it is meaningful to do a comprehensive study on the various impacts associated with river rafting so as to suggest the pathways to achieve the environmental sustainability in this region.In this study,we collected primary data from randomly selected population units across all stake holders such as local people(n = 100),and camp personnel(n = 22),through a pre-tested questionnaire survey between August 2009 and May 2010.The questionnaire contains issues on culture,social,economic,institutional and associated perceived impacts on pollution and biodiversity including views for sustainability.Secondary information was also collected from various sources and government records to supplement and strengthen the analysis.The impacts were analyzed qualitatively through a ranking mechanism to facilitate the decision making process.The perception of the interviewee about the various possible impacts of rafting was discussed with mitigating mechanism.The ranking analysis as percollected data reveals that economy and education of local community was improved significantly;however aquatic and terrestrial fauna,social cohesion and pollution(water,air,land) were significantly deteriorated.The results show that the existing practices are not sufficient to address the adverse impacts.Improvement in practices is necessary,mainly in the policy regime.Based on the analysis,some measures are recommended on how to protect community interest and environment with the development of river rafting as an ecotourism opportunity.     

苏轼诗歌与北宋文化的议论精神和淡雅精神

北宋文化吸纳了前此数千年的历史积淀 ,而皮毛落尽 ,精神独存 ,不仅各个文化领域、各类文化形式、各种雅俗文化百花齐放 ,更以独树一帜的北宋文化精神卓然自立。苏轼的诗歌正是在北宋这一特定历史时期的文化背景下孕育成长起来的。作为中国传统文化最具典型性的“文人”代表 ,苏轼通过其二千七百余首包赡丰富、变化万状的诗作 ,展现出了一幅北宋文化绚丽多彩的历时性的“清明上河图”。尤其引起我们注意的是 ,北宋文化精神中最为突出的两个方面———议论精神和淡雅精神 ,对苏轼诗歌产生了更为直接、更为深刻的影响 ,而苏诗的议论化和崇雅尚淡倾向又更为突出、更为集中、更为典型地代表了北宋文化的议论精神和淡雅精神     

互补的神话--鲁迅与张爱玲文学与人生观之比较

鲁迅和张爱玲 ,创造了二十世纪中国文学的两个神话。对照各自的文学创作与人生观 ,两者有着颇含默契的互补意味。不同的文学视角与精神关怀赋予彼此人格我不同的深度与质感 ;乡镇意识与城市情结使得两者的文学创作风格各异却又相得益彰 ;迥异的文化背景与人生阅历造成了彼此截然不同的人生态度