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阮于洲 《测绘与空间地理信息》2012,(3):219-220
分析了新时期测绘发展面临的新形势,对《中华人民共和国测绘法》规定的有关概念内涵、管理体制、运行机制、准入制度等的适应性进行了探讨,对进一步修订《中华人民共和国测绘法》提出了建议。 相似文献
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The Tornado Hazard In Southern New England: History,Characteristics, Student And Teacher Perceptions
《The Journal of geography》2012,111(6):258-266
Abstract People generally do not perceive New England to be tornado-prone. Yet, there is a long history of such storms in the six states going back to the late seventeenth century. Usually, New England tornadoes are small and short-lived; even so, some have caused many deaths and much property damage. There is a greater probability for a person to be affected by a tornado in southern New England than in much of the American Midwest. As building and population density increases, so does the hazard potential. Data from awareness surveys indicate that the lack of tornado knowledge remains a serious problem for teachers, students, and the public, and government information about such storms is not being widely disseminated. 相似文献
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《The Journal of geography》2012,111(3):105-112
Abstract Geography teacher preparation is an ongoing problem for the discipline. Changes in certification requirements and federal and state educational policies have diminished the role of colleges and universities in educating teachers. At the same time, geography education reform efforts have resulted in higher standards and an increased quantity of geography in the curriculum, pre-service programs have failed to produce an adequate supply of highly qualified geography teachers. This paper suggests that geographers implement geography mentoring programs to improve the quality of geography instruction in early-career teachers. A model developed for the National Geographic Society is described. The model uses Teacher Consultants as mentors to assist novice teachers at the stage in their development when they are most ready to improve practice: between years two and five of their career. 相似文献
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2008~2010年,在鱼类资源调查的基础上,分析了莫莫格国家级自然保护区的鱼类多样性特征。调查结果显示,莫莫格国家级自然保护区有鱼类物种5目11科42属49种,其中本区土著种5目10科38属45种,包括中国特有种4种,中国易危种5种,冷水种8种,国家II级保护动物1种。土著种群落中,有鲤形目(Cyprini-formes)鱼类32种,鲤科(Cyprinidae)鱼类29种,鮈亚科(Gobioninae)鱼类13种;古北界北方区黑龙江亚区黑龙江分区的物种为22种;源于东部平原和北方平原生态类群的鱼类有27种;适应于江—湖缓流环境和淡水定居生活的鱼类有33种;草上产卵和水层产卵繁殖的鱼类有37种;杂食性和初级肉食性种类有28种,它们均相对占优势。莫莫格国家级自然保护区与嫩江的鱼类群落物种结构Jaccard系数和Morisita-Horn相似性指数分别为0.918和0.838;稀有种(包括中国易危种)和常见种分别为14种和25种;物种多度格局近似于对数正态分布。这些结果表明,莫莫格国家级自然保护区的鱼类多样性与嫩江密切相关,鱼类区系复杂,物种组成与生态类型多样;群落结构相对较稳定,多样性程度相对较高,但仍面临着稀有种(包括中国易危种)尚占有一定比例而导致群落结构脆弱的潜在威胁。保持嫩江鱼类群落结构的稳定,对维护和发展莫莫格国家级自然保护区的鱼类多样性具有特别重要的意义。 相似文献
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The characteristics of long-distance dust transport from Asia to the United States over the Pacific Ocean are statistically analyzed using OMI AI (Ozone Monitoring Instrument Aerosol Index) data during 2005–2007. The results show that there is a high correlation of AI (the correlation coefficients are as high as 0.83 in March, 0.62 in April and 0.54 in May) between the Mongolia Gobi Desert and the west coast region of the United States (40°–50°N, 120°–130°W), indicating a strong source-receptor area relationship. Through calculating the lag correlation coefficient of the dust propagation time, we determined that the dust propagation time from the Mongolia Gobi Desert to the west coast of the United States is about 6–7 days at the 99% confidence level. 相似文献
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T. A. Semeniuk 《Australian Journal of Earth Sciences》2019,66(6):793-802
The geology of New South Wales is diverse, spanning Paleoproterozoic to modern materials and their various associated landforms and soils. In recognition of the intrinsic geological value of the State, around 150 geological sites were nominated to the now defunct Register of the National Estate, with the objective of geoconservation. However, these sites did not encompass the full range of geology of New South Wales; neither did they offer registered sites any protection. Analysis shows that the types of sites nominated were biased towards sedimentary and igneous rocks, and fossils, with under representation of metamorphic rocks, site-restricted soils, geomorphology and hydrogeology. To test the utility of the Brocx and Semeniuk ‘Geoheritage Toolkit’, a subset of the Register listings was re-examined, focusing on the Sydney Basin. Within the Sydney Basin, 59 nominated sites were reassessed using various geoheritage categories and the hierarchical framework of scale of the Toolkit. Four sites within the Sydney Basin were found to have features of international to national significance, and to have national historical value. These sites will need to be renominated for State and National listing. Clearly, to ensure that University teaching sites, as well as stratigraphic and lithologic type sections and reference sites, reflecting the geodiversity of New South Wales are conserved for future generations, a greater number of sites need to be put forward for heritage listing. 相似文献