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1.
1IntroductionArc-shaped bays are quite common on exposed sediment coast in South China, where the crenulate-bay beaches occur with the presence of two consecutive headlands and a predominant wave approach oblique to the alignment of the upcoast and downcoast headlands (Yasso, 1965). Oblique persistent swell striking a shoreline transports sediment alongshore and sculptures a coast into arc-shaped beaches. The shoreline of beach appearance mainly consists of straight segment and shadow segment…  相似文献   

2.
《极地研究》1992,3(2):45-55
After a field work on recently raised coastal features in South Shetland Islands, we conclude that there are three kinds of recent coastal features, i. e, fragmental coast, rock coast, and ice cliff coast. The processes and forms of the fragmental cost formed by wave action with floating ice are studied. Systermtic study of the raised coasts enables us to distinguish two groups of the coasts by an elevation of 20m a. s. l. The raised coasts above 20m a. s. l. belong to older group and those below 20m a. s. l. belong to younger group. Mean uplift rate of coast in this area is 6.7 mm/a.  相似文献   

3.
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   

4.
《中华人民共和国地貌图集》的研究与编制   总被引:6,自引:4,他引:2  
Geomorphologic maps are one of the most fundamental materials of the natural environment. They have been widely used in scientific research,resource exploration and extraction,education and military affairs etc. An editorial committee was established in 2001 to collect materials for researching and compiling a set of new 1:1,000,000 geomorphologic atlas of China. A digital geomorphologic database was created with visual interpretation from Landsat TM/ETM imageries and SRTM-DEM etc. The atlas compiled from the database was finished. The main characteristics of the atlas are as follows:Firstly,Landsat TM/ETM imageries,published geomorphologic maps or sketches,geographical base maps,digital geological maps,and other thematic maps were collected,which were uniformly geometrically rectified,clipped into uniform sheets,and stored in the foundation database. Secondly,based on the legends of 15 sheets 1:1,000,000 maps published in the 1980s,a geomorphologic classification system was built by combining morphology and genesis types. The system comprised seven hierarchical layers:basic morphology,genesis,sub-genesis,morphology,micro-morphology,slope and aspect,material composition and lithology. These layers were stored in the database during visual image interpretation. About 2000 kinds of morpho-genesis and 300 kinds of morpho-structure were interpreted. Thirdly,the legend system was built,which included color,symbol bases and note bases etc.,compilation standards and procedures were developed,74 sheets of 1:1,000,000 covering all land and sea territories of China were compiled,the 1:1,000,000 geomorphologic atlas of the People’s Republic of China was finished and published. The atlas will fill the blanks in national basic scale thematic maps,and the geomorphologic database could be applied widely in many fields in the future.  相似文献   

5.
Based on 22 sparse-distributed tide gauge records in the Northwest Pacific Ocean marginal sea, the process, characteristic and prediction of regional sea level change are discussed by the integration of the following methods. Firstly, the regularized EM algorithm (RegEM) and the Multi-taper Spectral Method (MTM) are adopted to interpret their multiscale fluctuation processes and their spatial-temporal variations. Secondly, the orderly cluster method is introduced to classify these tidal stations, and with the consideration of the space adjacent relation, we obtain five sub-regions (the coasts of Bohai Sea-northern Yellow Sea, Yellow Sea-East China Sea along Chinese coast, the East China Sea along Japanese coast, the southern East China Sea and the northwestern South China Sea). Furthermore, the Mean Generation Function (MGF) is explored to predict the medium- and long-term trends of each tide station. Finally, the Principal Component Analysis (PCA) is employed to obtain re-gional-scale sea level change trends, sea level rise rates of the above five sub-regions from 2001 to 2030 are 1.23-1.27 mm/a, 3.30-3.34 mm/a, 2.72-2.76 mm/a, 1.43-1.47 mm/a and 1.13-1.15 mm/a respectively, and the whole region sea level rise rate is between 2.01 mm/a and 2.11 mm/a. The aim of our work is to conduct an integrated research on regional sea level change.  相似文献   

6.
《地理学报》2009,30(4):471-488
This paper analyzed the anomalous low-temperature events and the anomalous rain-abundant events in January since 1951 and winter since 1880 for southern China.The anomalous events are defined using ±1σ thresholds.Twelve cold Januaries are identified where temperature anomaly below-1σ,and ten wet Januaries are identified where precipitation anomaly above +1σ.Among these events there are three patterns of cold-wet Januaries,namely 1969,1993 and 2008.The NCEP/NCAR reanalysis data are used to check the atmospheric circulation changes in association with the anomalous temperature and precipitation events.The results show that the strong Siberian High(SBH),East Asian trough(EAT) and East Asian jet stream(EAJS) are favorable conditions for low-temperature in southern China.While the anomalous southerly flow at 850 hPa,the weak EAT at 500 hPa,the strong Middle East jet stream(MEJS) and the weaker EAJS are found to accompany a wetter southern China.The cold-wet winters in southern China,such as...更多 January of 2008,are mainly related to a stronger SBH,and the circulation in the middle to upper troposphere is precipitation-favorable.In wet winters,the water vapor below 500 hPa is mainly transported by the anomalous southwesterly flow and the anomalous southern flow over the Indo-China Peninsula and the South China Sea area.The correlation coefficients of MEJS,EAMW(East Asian meridional wind) and EU(Eurasian pattern) to southern China precipitation in January are +0.65,-0.59 and-0.48 respectively,and the correlations for high-pass filtered data are +0.63,-0.55 and-0.44 respectively,the significant level is all at 99%.MEJS,EAMW and EU together can explain 49.4% variance in January precipitation.Explained variance for January and winter temperature by SBH,EU,WP(west Pacific pattern) and AO(Arctic Oscillation) are 47.2% and 51.5%,respectively.There is more precipitation in southern China during El Nio winters,and less precipitation during La Nia winters.And there is no clear evidence that the occurrence of anomalous temperature events in winter over southern China is closely linked to ENSO events.  相似文献   

7.
中国南方冬季异常低温和降水事件   总被引:6,自引:1,他引:5  
This paper analyzed the anomalous low-temperature events and the anomalous rain-abundant events in January since 1951 and winter since 1880 for southern China.The anomalous events are defined using ±1σ thresholds.Twelve cold Januaries are identified where temperature anomaly below-1σ,and ten wet Januaries are identified where precipitation anomaly above +1σ.Among these events there are three patterns of cold-wet Januaries,namely 1969,1993 and 2008.The NCEP/NCAR reanalysis data are used to check the atmospheric circulation changes in association with the anomalous temperature and precipitation events.The results show that the strong Siberian High(SBH),East Asian trough(EAT) and East Asian jet stream(EAJS) are favorable conditions for low-temperature in southern China.While the anomalous southerly flow at 850 hPa,the weak EAT at 500 hPa,the strong Middle East jet stream(MEJS) and the weaker EAJS are found to accompany a wetter southern China.The cold-wet winters in southern China,such as...更多 January of 2008,are mainly related to a stronger SBH,and the circulation in the middle to upper troposphere is precipitation-favorable.In wet winters,the water vapor below 500 hPa is mainly transported by the anomalous southwesterly flow and the anomalous southern flow over the Indo-China Peninsula and the South China Sea area.The correlation coefficients of MEJS,EAMW(East Asian meridional wind) and EU(Eurasian pattern) to southern China precipitation in January are +0.65,-0.59 and-0.48 respectively,and the correlations for high-pass filtered data are +0.63,-0.55 and-0.44 respectively,the significant level is all at 99%.MEJS,EAMW and EU together can explain 49.4% variance in January precipitation.Explained variance for January and winter temperature by SBH,EU,WP(west Pacific pattern) and AO(Arctic Oscillation) are 47.2% and 51.5%,respectively.There is more precipitation in southern China during El Nio winters,and less precipitation during La Nia winters.And there is no clear evidence that the occurrence of anomalous temperature events in winter over southern China is closely linked to ENSO events.  相似文献   

8.
中国生态地理区域系统区划   总被引:8,自引:3,他引:5  
Eco-geographic regionalization has been one of the most important topics in China‘s regionalization researches since the end of the 20th century. It is a major ecosystem in geographic zonality. A hierarchical system, which is formed by division or combination of natural features based on geographic relativity and comparison of major ecosystem factors (including biological and non-biological) and geographic zonality, is called eco-geographic regional system. This paper introduces process of China‘s regionalization development. The first level unit, temperature zone, is delineated with main criteria of temperature. The second level unit, humidity region, is based on criteria of water/moisture states. The third level unit, natural region, is divided according to medium geomorphologic units. Vegetation types and soils are applied as supplementary criteria to indicate temperature and water/moisture states. Mapping process from qualitative to quantitative and China‘s eco-geographic regional system are also explained in this paper.  相似文献   

9.
《极地研究》1991,2(1):10-21
From the surface mass accumulation data in year of 1987/88, the distribution and variation of annual mass balance on Mizuho Plateau are discussed. The authors also analyze the effects of shortterm climatic and topographical variations on the mass balance. It is found that there are some differences in spatial distribution and annual average state in the year of 1987/88 and other years. Ia the area at elevation lower than 550 m near the coast, the mass balance appears to be negative. The annual mass balance over 80 km distance from S_(16) to inland is 0.84m snow depth. A low mass balance zone from 80 km site to Mizuho Station, is considered to be only 0.14 m snow depth. It is found from the comparison of mass balances that the mass-balance level on the glaciers in West China is 9 times higher than that on Mizuho Plateau, where the massbalance level appears to be low accumulative and low expensive, but inverse in middle and low latitude regions, such as on glaciers in West China. The effects of short-term  相似文献   

10.
中国畜禽养殖的空间分析及分区研究(英文)   总被引:3,自引:1,他引:2  
The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world’s top first in recent 20 years. Livestock emissions and pollution is closely associated with its population and spatial distribution. This paper aims to investigate the spatial patterns of livestock and poultry breeding in China. Using statistical yearbook and agricultural survey in 2007, the county-level populations of livestock and poultry are estimated as equivalent standardized pig index (ESP), per cultivated land pig index (PCLP) and per capita pig index (PCP). With the help of spatial data analysis (ESDA) tools in Geoda and ArcGIS software, especially the Moran’s I and LISA statistics, the nationwide global and local clustering trends of the three indicators are examined respectively. The Moran’s I and LISA analysis shows that ESP and PCP are significantly clustering both globally and locally. However, PCLP is clustering locally but not significant globally. Furthermore, the thematic map series (TMS) and related gravity centers curve (GCC) are introduced to explore the spatial patterns of livestock and poultry in China. The indicators are classified into 16 levels, and the GCCs for the three indicators from level 1 to 16 are discussed in detail. For districting purpose, each interval between gravity centers of near levels for all the three indicators is calculated, and the districting types of each indicator are obtained by merging adjacent levels. The districting analysis for the three indicators shows that there exists a potential uniform districting scheme for China’s livestock and poultry breeding. As a result, the China’s livestock and poultry breeding would be classified into eight types: extremely sparse region, sparse region, relatively sparse region, normally sparse region, normal region, relatively concentrated region, concentrated region and highly concentrated region. It is also found that there exists a clear demarcation line between the concentrated and the sparse regions. The line starts from the county boundary between Xin Barag Left Banner and Xin Barag Right Banner, Inner Mongolia Autonomous Region to the west coast of Dongfang County, Hainan Province.  相似文献   

11.
Coastline configuration indexes of 34 typical arc-shaped coasts in South China are investigated by the method of principal component analysis, and meanwhile deposition and geomorphologic features of arc-shaped coast are also analyzed. The results show: (1) The configuration of arc-shaped coast in South China is of the characteristic of variability and complexity. (2) The wave power and the openings of the bay are the decisive factors to result in the changes of the configuration of the arc-shaped coast in South China, however, incidence direction of the wave has no effect on configuration development of the coast. (3) Commonly, geomorphologic modes of the arc-shaped coast system in South China consist of barriers, lagoons and tidal-inlets, and can be divided into four types: the openings of the bay leaning to the east, the openings of the bay leaning to the south, the openings of the bay leaning to the west and the openings of the bay leaning to the north.  相似文献   

12.
华南弧形海岸岸线形态与地貌发育模式   总被引:2,自引:0,他引:2  
戴志军  李春初 《地理学报》2004,59(5):738-744
利用主成分分解方法对华南34个典型弧形海岸线形态指标进行研究,同时分析华南弧形海岸的沉积、动力及其地貌等特征,结果表明:(1) 华南弧形海岸的形态具有多样性与复杂性特征。(2) 波浪的入射方向对海岸的形态发育不起作用,海湾的开口和波浪强度是海岸形态发生变化的重要因子。(3) 华南弧形海岸体系的地貌发育模式一般由堡岛、潟湖及其潮汐通道组成,并主要可分为海湾偏E型、海湾偏S型、海湾偏W型和海湾偏N型等4种发育模式。  相似文献   

13.
华南海岸带陆海相互作用研究   总被引:1,自引:0,他引:1  
全球环境变化背景下,海岸带陆海相互作用的重点应该放在地球系统的重要界面-海岸带。结合国外海岸带陆海相互作用研究,对我国华南海岸带历史与现代陆海相互作用研究的现状与问题进行较为详细的评述,并就华南海岸带开展陆海相互作用应研究的主要内容及趋势进行了探讨。  相似文献   

14.
通过提取1975年与2010年左右南海海岸带建设用地信息,并对南海海岸带区域进行地貌分区,分析了不同类型海岸带35年建设用地扩张空间格局.结果表明:① 华南大陆和马来半岛建设用地扩张普遍快,中南半岛扩张程度中等,苏门答腊岛,加里曼丹岛和菲律宾群岛除马尼拉湾外普遍扩张程度慢.② 不同海岸地貌因自然资源条件,开发难易程度,腹地大小不同,其建设用地扩张程度差异显著.三角洲平原岸和河口平原岸因水运条件好,腹地广,建设用地扩张普遍显著,台地岸和沙坝--潟湖平原岸因适宜建中小型港口,扩张较为显著,海湾平原岸与山地岸则因平原面积小,开发潜力有限,建设用地扩张普遍不大,平直沙堤平原岸因腹地小,水运不发达而扩张甚微.③ 不同类型海岸带开发模式各异.三角洲平原岸和河口平原岸建设用地空间形态多样化,山地岸,台地岸,海湾平原岸以团块状或条带状为主,沙坝--潟湖平原岸以团块状与星状为主,平直沙堤平原岸多呈条带状,线状或点状分布.  相似文献   

15.
华南港湾海岸的地貌特征   总被引:12,自引:1,他引:12  
本文根据作者参加华南海岸和港口调查研究的体会,对华南现代海岸的形成条件和港湾海岸的地貌特点进行分析。  相似文献   

16.
海南岛现代风成岩(沙丘岩)的形成及其地貌意义   总被引:3,自引:0,他引:3  
吴克刚 《地理研究》1988,7(2):67-72
本文从沉积物结构、沉积结构特征以及胶结物类型等方面区别海岸沙丘岩、沙堤岩和海滩岩,并探讨了沙丘岩的形成机制及环境意义。  相似文献   

17.
华南沿海全新世沙坝及其改造利用   总被引:2,自引:0,他引:2  
李平日 《地理学报》1990,45(4):467-474
华南沿海沙坝为中、晚全新世形成,分为六个形成期。分析了沙坝的粒度和沉积 寺征及其分布规律。提出华南全新世沙坝的形成与砂源丰富、波浪较强、海平面已与现今相近、 勾造运动相对稳定、季风气候等条件有密切关系。认为沙坝对环境的主要不良影响是:1.产 上风沙灾害;2.烂湾坝阻塞或淤浅航遭。为此提出营造针阔叶混交防风林及配种草本、灌木 向意见。这些沙坝的主要有利因素是:且.含丰富的砂矿:2.形成漏湖式港湾;3.提烘发展农 木牧渔业的广阔空间;咯.可作为建设经济特区。沿海开发区和发展海滨旅游的土地资源。  相似文献   

18.
根据 1960―2013 年华南沿海 7 个海洋站的实测海表温度(SST)及全球平均表面温度、太平洋年代际涛动(PDO)、ENSO、南海高压、华南沿海近海面风速等资料,采用线性回归、Yamamoto 突变检验、小波分析、相关分析等方法,研究了近 54 a 华南沿海 SST 时空变化及其影响因子,结果表明:1)近 54 a 华南沿海的年平均 SST呈准同步变化和显著增暖趋势,其气候倾向率为 0.08~0.17℃/10 a,平均为 0.12℃/10 a,以冬季增暖最为显著;2)SST 变化在 1997/1998 年出现突变现象;3)SST 变化有多时空尺度的变化特征,其中最显著的变化周期是 2~4 a的年际变化;4)SST 变化深受 ENSO 事件的影响,约滞后于 MEI 指数 2~4 个月;5)影响 SST 变化趋势的主要因子有全球气候变暖、PDO、南海高压、华南沿海近海面层风速等。  相似文献   

19.
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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