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1.
国家自然科学基金项目资助的地貌学研究现状与效应   总被引:2,自引:2,他引:0  
程维明  刘樯漪  申元村 《地理学报》2016,71(7):1255-1261
通过对2010-2015年国家自然科学基金资助下地貌学研究项目的总体状况、项目类型、依托单位、研究区域、人才队伍、研究热点、成果产出、获奖及社会效应等方面的分析,归纳概括地貌学的研究现状与态势等。结果表明:近5年来,地貌学获得的资助项目呈上升趋势,相关研究不断深入,各类研究团队显著壮大;研究系统已由高等院校为主逐渐发展成高等院校与科研机构并行的格局;不同地域地貌学研究的发展程度、研究对象及热点问题均表现出一定的区域不均衡性;构造、河流水文、黄土、冰川、风沙等是目前中国地貌学研究的主体方向。从资助项目的研究成果和产生效应来看,地貌学研究得到恢复和较快速发展,发表论文的数量和质量稳步提升,资助项目成果获奖层次高、社会效益显著。  相似文献   
2.
复杂系统理论与Agent模型在土地变化科学中的研究进展   总被引:15,自引:4,他引:11  
基于复杂系统理论与Agent 模型,分别从理论与方法的角度梳理并总结了当前土地变化科学的研究进展。复杂系统理论为研究土地变化所处的“耦合的人类-自然系统”及其复杂性问题提供理论支撑;而基于Agent 的模拟作为研究复杂系统的重要工具,为传统土地变化模拟提供新的方法支持。当前,ABMs与土地变化模型相结合(ABM/LUCC),无论是模型构建还是模型应用均取得了显著进展。然而,其也存在诸多问题,尤其是理论与应用脱节,使很多建模者容易陷入“为建模而建模”的误区。此外,现有的ABM模型设计较为随意,模型间差异太大,不利于跨区域比较研究的开展。因此,虽然ABM是认识复杂系统的有效方法,但是建模之前离不开对系统复杂性的深入研究;基于Agent 的土地变化模拟的意义在于充分表达“人类-自然”系统的综合复杂关系,从而合理的预测土地变化(结构与功能) 的动态过程,解释并评价土地变化的可能影响。  相似文献   
3.
Lunar landforms are the results of geological and geomorphic processes on the lunar surface. It is very important to identify the types of lunar landforms. Geomorphology is the scientific study of the origin and evolution of morphological landforms on planetary surfaces. Elevation and relief amplitude are the most commonly used geomorphic indices in geomorphological classification studies. Previous studies have determined the elevation classification criteria of the lunar surface. In this paper,...  相似文献   
4.
Cultivated land change in the Belt and Road Initiative region   总被引:2,自引:1,他引:2  
The Belt and Road Initiative (BRI)–a development strategy proposed by China – provides unprecedented opportunities for multi-dimensional communication and cooperation across Asia, Africa and Europe. In this study, we analyse the spatio-temporal changes in cultivated land in the BRI countries (64 in total) to better understand the land use status of China along with its periphery for targeting specific collaboration. We apply FAO statistics and GlobeLand30 (the world’s finest land cover data at a 30-m resolution), and develop three indicator groups (namely quantity, conversion, and utilization degree) for the analysis. The results show that cultivated land area in the BRI region increased 3.73×104 km2 between 2000 and 2010. The increased cultivated land was mainly found in Central and Eastern Europe and Southeast Asia, while the decreased cultivated land was mostly concentrated in China. Russia ranks first with an increase of 1.59×104 km2 cultivated land area, followed by Hungary (0.66×104 km2) and India (0.57×104 km2). China decreased 1.95×104 km2 cultivated land area, followed by Bangladesh (–0.22×104 km2) and Thailand (–0.22×104 km2). Cultivated land was mainly transferred to/from forest, grassland, artificial surfaces and bare land, and transfer types in different regions have different characteristics: while large amount of cultivated land in China was converted to artificial surfaces, considerable forest was converted to cultivated land in Southeast Asia. The increase of multi-cropping index dominated the region except the Central and Eastern Europe, while the increase of fragmentation index was prevailing in the region except for a few South Asian countries. Our results indicate that the negative consequence of cultivated land loss in China might be underestimated by the domestic- focused studies, as none of its close neighbours experienced such obvious cultivated land losses. Nevertheless, the increased cultivated land area in Southeast Asia and the extensive cultivated land use in Ukraine and Russia imply that the regional food production would be greatly improved if China’ “Go Out policy” would help those countries to intensify their cultivated land use.  相似文献   
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6.
自明代杰出的地图学家罗洪先(1504-1564年)所编制的《广舆图》(1541年)和利玛窦带来西方精确地图测绘技术开始,中国的地图制图技术已经迈入了近代地图学的门槛,因此,明-清-民国是中国近代地图学从雏形走向成熟的完整阶段[1]。随着现代地图的应用与发展广泛、深入,抽象的概括型地图符号及普通的二维平面地图已不能满足读图者的需求,制图者开始探索虚拟现实、三维地图等表达方法,这与中国近代传统制图的写景法有异曲同工之处。所以,对中国近代地图制图技术及表现方法的研究,对于现代地图学的发展具有重要作用。本文通过阅读大量的中国近代(即明、清、民国时期)的地图资料,查阅前人的研究资料,总结和提炼了中国明、清、民国3个不同时期地图制图的技术,分别阐述了3个时期地图要素、表示方法及其制图技术的发展。  相似文献   
7.
月球地貌是月球表面发生的地质和地貌过程的结果,月球地貌单元的划分和等级分类体系的构建是月球地貌学研究的基础,也是月球地貌图制图的基础和关键科学问题。地貌学是研究形态和成因的科学,高程和起伏度是最基本的地貌指标。本文基于LOLA(Lunar Orbiter Laser Altimeter) DEM数据以及LOLA和SELENE TC(Terrain Camera)融合的DEM数据(SLDEM2015,文中简称SLDEM),利用均值变点法确定月表起伏度计算的最佳窗口,并以起伏度100 m、200 m、300 m、700 m、1500 m及2500 m为阈值将月球表面分为微起伏平原(< 100 m)、微起伏台地[100 m, 200 m)、微小起伏丘陵[200 m, 300 m)、小起伏山地[300 m, 700 m)、中起伏山地[700 m, 1500 m)、大起伏山地[1500 m, 2500 m)及极大起伏山地(≥ 2500 m)地貌7个类型。划分结果显示:微起伏平原主要分布在月海平原区域、部分有玄武岩充填的撞击盆地的盆底区域以及撞击坑坑底区域;微起伏台地主要分布在月海和月陆区域的交界区域;微小起伏丘陵主要分布在月溪和皱脊等构造单元区域;小起伏山地主要分布在撞击坑中央峰及坑底断裂区域;中起伏山地主要分布在撞击坑坑底和坑壁过渡区域、撞击坑坑壁和坑缘过渡区域、撞击盆地盆底与盆壁过渡区域以及盆壁与盆缘过渡区域;大起伏和极大起伏山地主要分布在撞击坑坑壁区域及撞击盆地盆壁区域。本文确定的月表起伏度分级标准可以对月表数字地貌分类体系的构建和月球地貌图集的编研提供定量标准和重要参考。  相似文献   
8.
Gao  Xiaoyu  Cheng  Weiming  Wang  Nan  Liu  Qiangyi  Ma  Ting  Chen  Yinjun  Zhou  Chenghu 《地理学报(英文版)》2019,29(2):180-196
Journal of Geographical Sciences - Landforms are an important factor determining the spatial pattern of cropland through allocation of surface water and heat. Therefore, it is of great importance...  相似文献   
9.
中国地貌区划理论与分区体系   总被引:2,自引:1,他引:1  
Geomorphological regionalization(geomor-region)and geomorphological type(geomor-type)classification are two core components in the geomorphologic research.Although remarkable achievements have been made in the study of geomor-region,many deficiencies still exist,such as the inconsistency of landform indicators,the small quantity of division orders,disparities of geomorphological characteristics,differences of mapping results,and the small scale of zoning maps.Requirements for improved national geomor-regions are therefore needed for the purpose of an enhanced national geo-information system.Based on theories of geomor-region in China including plate tectonics,crustal features,endogenic and exogenic forced geomorphological features,and regional differentiations of geomor-type,a three-order(major-region,sub-region,and small-region)research program on China’s geomor-regions is proposed on the basis of previous 2013 geomor-region system.The major contents of the new geomor-region scheme are:(1)principles of the national multi-order geomor-regions;(2)hierarchical indicator systems of geomor-regions including characteristics of the terrain ladder under the control of tectonic setting,combinations of regional macro-form types,combinations of endogenic and exogenic forces and basic types of morphology,combinations of regional morphological types,and combinations of regional micro-morphological types;(3)naming rules and coding methods of geomor-regions;and(4)precise positioning techniques and methods of multi-order geomor-region divisions based on multi-source data.Using the new geomor-region theory and division methodology,the partition of national three-order geomor-regions of China was successfully constructed.The geomor-region system divided China into six first-order major-regions,36 second-order sub-regions,and 136 third-order small-regions.In addition,a database and management information system of the national geomor-regions were established.This research has an important guiding significance for promoting the development of China’s regional geomorphology and for practical applications based on geomor-regions.  相似文献   
10.
Geomorphology is one of the main subdisciplines of geography. The research achievements and prospects in geomorphology have received considerable attention for a long time. In this paper, a general retrospect of geomorphologic research in China over the past 60 years was firstly addressed, especially the research progress during the last 40 years. Based on a summary of experience and a tendency of development, perspectives of geomorphologic research direction in the future were provided. It is concluded that the discipline of geomorphology has made great progress in the aspects of geomorphologic types, regionalization, as well as their subdisciplines such as dynamic geomorphology, tectonic geomorphology, climatic geomorphology, lithological geomorphology, palaeogeomorphology. We believe that persisting in the unity principle between morphological and genetic types would be conductive for the development of traditional landforms and integrated landforms. In addition, five perspectives aim to enhance China’s geomorphologicl research capacity were proposed. They are: (1) strengthening the research of basic geomorphologic theory and the research of integrated geomorphology to expand the research space; (2) focusing more on the research of geomorphologic structure and geomorphologic function to improve the application ability of geomorphology; (3) constructing a comprehensive resource, environmental, and geomorphologic information system and building a sharing platform to upgrade the intelligent information industry of geomorphology; (4) putting more efforts on the research of coastal geomorphology and marine geomorphology to assist the transformation of China from a maritime country to an ocean power; and (5) cultivating talents and constructing research teams to maintain a sustainable development of China’s geomorphologic research.  相似文献   
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