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71.
Topographic maps and aerial photographs are particularly useful when geoscientists are faced with fieldwork tasks such as selecting paths for observation, establishing sampling schemes, or defining field regions. These types of images are crucial in bedrock geologic mapping, a cognitively complex field-based problem-solving task. Geologic mapping requires the geologist to correctly identify rock types and three-dimensional bedrock structures from often partial or poor-quality outcrop data while navigating through unfamiliar terrain. This paper compares the walked routes of novice to expert geologists working in the field (n = 66) with the results of a route planning and navigation survey of a similar population of geologists (n = 77). Results show clearly that those geologists with previous mapping experience make quick and decisive determinations about field areas from available imagery and maps, regardless of whether they are or not physically present in the field area. Recognition of geologic features enabled experts to form and verbalize a specific plan for travel through a landscape based on those features. Novices were less likely to develop specific travel route plans and were less likely to identify critical landscape cues from aerial photographs.  相似文献   
72.
Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy(ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points(GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart(ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for stratigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China(geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China(geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation(2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China.  相似文献   
73.
The Basic Ocean Law (BOL) and Basic Ocean Plan (BLP) are important guarantee for the maritime strategy of Japan, which has established a complete policy system for the development of marine science and technology. On the other hand, the Japanese Government has started some major marine strategies and plans to promote the BLP. In this paper, the marine science and technology plans launched by the Japanese Government and its participation in the international cooperative research projects were introduced. The research of Japan Marine Science and Technology Center and the University of Tokyo Institute of Oceanography in the long-term planning and focus on the layout features, deep sea research technology layout, contents and advanced equipment were analyzed. At last, some recommendations for China’s development on marine science and technology were proposed, such as strengthening the legislation work and process, carrying out research and development of marine infrastructure with independent intellectual property rights, actively participating in international large-scale ocean plan, improving the discourse right and enhancing national maritime awareness and suggestions and so on.  相似文献   
74.
For 15 years since the beginning of China Argo project, China has deployed over 350 profiling floats in Pacific and Indian ocean, and constructed China Argo ocean observing network. Moreover, we have setup the Argo data receiving, processing and distributing system, and developed various Argo data products using Argo observations, which has promoted the progress of ocean data sharing in China. The abundant Argo data have become a main data source in oceanic and atmospheric basic researches and operational applications. A batch of important achievements in basic research and operational application have been brought, e.g. in aspects of tropical cyclone (typhoon), ocean circulation, meso-scale eddy, turbulence, heat/salt storage and transport and water mass, as well as in ocean, atmosphere/climate operational forecasting and predicting. With the extension of the international Argo program from “Core Argo” to “Global Argo”, we are faced with great challenges in the long-term maintaining and sustained developing of our Argo ocean observing network. It is suggested that we should take the opportunity to construct China regional Argo ocean observing network as soon as possible in adjacent northwestern Pacific and Indian ocean using Chinese BeiDou profiling floats, which will make us to take responsibility and obligation of a big country for addressing global climate changes and preventing natural disasters.  相似文献   
75.
Marine scientific research is crucial to forge solutions in the development of a new international legally binding instrument for the conservation and sustainable use of marine biological diversity in areas beyond national jurisdiction (ABNJ) under the 1982 United Nations Convention on the Law of the Sea . The transfer of marine technology, capacity development and marine genetic resources are key issues. This paper examines how the Intergovernmental Oceanographic Commission (IOC), as a competent international organisation for marine scientific research and technology transfer, can inform the development of the instrument. Synergies between marine technology transfer and non-monetary benefit sharing of genetic resources are illustrated. Four key lessons from the IOC are examined: 1. Coordinating international cooperation in marine scientific research; 2. Enabling open access to data and knowledge; 3. Facilitating capacity development through scientific training and education; and 4. Governance of marine scientific research. Realising the potential of the IOC to advance governance solutions for ABNJ will depend on increased political will from Member States and strengthened partnerships to reduce resource constraints and enhance the IOC's capacity at global and regional scales.  相似文献   
76.
The Belt and Road initiative has a significant focus on infrastructure, trade, and economic development across a vast region, and it also provides significant opportunities for sustainable development. The combined pressure of climate variability, intensified use of resources, and the fragility of ecosystems make it very challenging, however, to achieve future sustainability. To develop the path in a sustainable way, it is important to have a comprehensive understanding of these issues across nations and evaluate them in a scientific and well-informed approach. In this context, the Digital Belt and Road (DBAR) program was initiated as an international venture to share expertise, knowledge, technologies, and data to demonstrate the role of Earth observation science and technology and big Earth data applications to support large-scale development. In this paper, we identify pressing challenges, present the research priorities and foci of the DBAR program, and propose solutions where big Earth data can make significant contributions. This paper calls for further joint actions and collaboration to build a digital silk road in support of sustainable development at national, regional and global levels.  相似文献   
77.
随着预应力锚索在湿陷性黄土边坡加固工程中的广泛应用,其耐久性问题就变得日益突出,湿陷性黄土边坡预应力锚索出现了较多因预应力损失而引起的失效事故。基于湿陷性黄土边坡预应力锚索运行现状进行研究,研究表明:黄土腐蚀性对边坡预应力锚索耐久性影响微弱,黄土湿陷性和地质条件变化对边坡预应力锚索耐久性影响显著;通过采用加强排水措施、提升浅部注浆工艺和注重运行维护等措施可以改善湿陷性黄土边坡预应力锚索耐久性;改善后的预应力锚索在监测期内处于平稳波动的服役状态,运行效果良好。本研究以期为湿陷性黄土边坡预应力锚索的设计、施工和运行维护等提供借鉴。  相似文献   
78.
一次冰雹天气过程的云系发展演变及云物理特征研究   总被引:5,自引:1,他引:4  
张小娟  陶玥  刘国强  彭宇翔 《气象》2019,45(3):415-425
利用中尺度数值模式WRF(Weather Research and Forecasting)的数值模拟,结合NECP/FNL再分析资料、地面、探空、多普勒雷达基数据和卫星产品等观测资料,综合分析了2014年3月30日发生在贵州省西南部的一次冰雹天气过程。研究了有利于冰雹发生的环流特征和环境条件,分析了冰雹云系的发展演变特征、云微物理结构特征,初步分析了冰雹形成的云物理机制。结果表明:此次冰雹天气是典型的低压辐合线型降雹类型,地面降雹位置位于700 hPa切变线和近地面辐合线附近及南侧;发生此次冰雹过程的对流云系经历了对流云系的初生阶段、合并加强阶段、成熟降雹阶段和东移阶段。贵州地区上空对流云系的微物理结构具有混合相云特征,高层为冰晶、雪,中层为云水、霰,低层为雨水、冰雹。霰和云水是形成雨水和冰雹的主要来源,霰撞冻过冷云水和霰的自动转化是冰雹形成的主要微物理机制。  相似文献   
79.
基于遥感的城市热岛效应研究   总被引:15,自引:0,他引:15  
热红外遥感和气候学的交叉融合为城市热岛效应提供了新的研究方法。从城市热岛的空间分布与土地利用类型、植被覆盖关系、人为热关系以及城市热岛效应演变4方面分析热红外遥感在城市热岛研究中的应用现状;探讨目前存在的两个主要问题:城市地物真实温度难以获取,遥感和气候模型结合不密切;提出遥感和气候模型结合以及多平台、多尺度、多角度遥感的综合应用等是城市热岛效应遥感研究的发展趋势。  相似文献   
80.
我国区域规划编制与实施问题研究进展   总被引:2,自引:1,他引:1  
针对近年区域规划编制与实施问题成为规划学者关注的焦点问题之一,从区域规划目标、规划内容、规划程序、规划管理4方面对国内学者10多年的研究观点进行梳理和评析。指出应加强规划间协调和衔接、规划实施手段实证分析等方面的研究,同时应从渐进式社会经济体制变迁角度来把握我国区域规划理论的变革方向。  相似文献   
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