基于GEE和遥感大数据的1986—2015年全球城镇用地扩张占用水体时空特征     

冯凯东  毛德华  王宗明  蒲海光  杜保佳  仇志强 《地理科学》2022,42(1):143-151

以全球年度城市动态数据（GAUD）和全球地表水动态数据集（GSW）为基础数据,利用Google Earth Engine（GEE）解析了1986—2015年全球城镇用地扩张占用永久性和季节性水体的时空分布特征。研究发现：30 a间全球城镇用地扩张直接占用水体的面积为1 033.2 km²,其中包括季节性水体711.7 km²和永久性水体321.5 km²,呈现先增加后降低的变化趋势。亚洲是城镇用地扩张占用水体面积最多的大洲,其次是北美洲和欧洲,占用水体的面积分别为799.4 km²、122.5 km²和61.1 km²。欧洲是唯一以占用永久性水体为主的大洲。陆地面积排名前十的国家中,中国、美国和印度是城镇用地扩张占用水体面积最多的国家,占用水体的面积分别为573.1 km²、109.6 km²和24 km²。以占用永久性水体为主的国家是俄罗斯和阿尔及利亚。尽管世界各国在水资源保护方面做出了巨大努力,但实现联合国可持续发展目标背景下,需防控更多的水体因城镇用地扩张而消失。  相似文献   

贵州都匀下泥盆统蟒山群Zosterophyllum australianum(澳大利亚工蕨)新材料及其古地理意义^*          下载免费PDF全文

周志强  赵景宇  王嘉树  吴成洋  肖彪  黄璞 《古地理学报》2022,24(3):479-492

Zosterophyllum(工蕨属)是早期陆生植物的代表性类群之一,全球广泛分布。Z.australianum(澳大利亚工蕨)产自华南和澳大利亚,是东北冈瓦纳古植物地理区系的典型分子。文中描述了产自贵州都匀包阳剖面蟒山群中的Z.australianum新材料。该标本的孢子囊具短柄,呈椭圆形或扇形,宽2.6~4.1 mm,高可达3.9 mm,加厚带宽约0.6 mm,紧密螺旋排列形成孢子囊穗,与云南文山早泥盆世坡松冲植物群中的Z. australiaunum极为相似。依据目前对Z. australianum时代延限的认识,并结合蟒山群其他植物属种的发现(如Adoketophyton subverticillatum),推断该群下段的时代为早泥盆世布拉格期。Z. australianum在蟒山群中的发现,扩展了该植物的地理分布范围,反映出蟒山群中的植物组合与坡松冲植物群存在一定联系。  相似文献   

甘肃金塔县碱凹井岩体岩石地球化学特征及构造环境分析     

蒲万峰  严镜  汪宏涛  王舒恒  刘景显 《新疆地质》2015,(2):263-269

甘肃金塔县东北的张家疙瘩一带发育大量侵入岩体,碱凹井岩体出露规模较大,侵入蓟县系平头山组,北东局部侵入石炭系干泉组,岩性主要为二长花岗岩和正长花岗岩。岩石组合类型和岩石地球化学研究表明,碱凹井岩体SiO2含量71.59%~75.86%,平均74.06%,Na2O含量3.73%~4.10%,K2O含量4.55%~4.76%,铝饱和指数A/CNK=1.04~1.20,稀土元素总量为79.95×l0-6~201.65×l0-6,(La/Yb)N=1.05~2.24,球粒陨石标准化分布模式图总体呈略微右倾的V字型,具相对平缓的富集轻稀土元素稀土分布模式。重稀土元素分馏不明显且相对亏损,Eu具明显负异常,δEu=0.07~0.36。在微量元素原始地幔标准化蛛网图上,亏损Ba,Nb,Sr,Ti,富集Rb,Th,K。结合区域地质背景认为,该岩体形成于后碰撞伸展作用阶段,可能源于幔源岩浆底侵,导致上覆年轻地壳(可能为洋壳和岛弧建造组成)部分熔融,并发生了较强的结晶分异作用。  相似文献   

Projection and possible causes of summer precipitation in eastern China using self-organizing map     

Mei Li  Zhihong Jiang  Pu Zhou  Herv&#; Le Treut  Laurent Li 《Climate Dynamics》2020,54(5):2815-2830

Self-organizing map (SOM) is used to simulate summer daily precipitation over the Yangtze–Huaihe river basin in Eastern China, including future projections. SOM shows good behaviors in terms of probability distribution of daily rainfall and spatial distribution of rainfall indices, as well as consistency of multi-model simulations. Under RCP4.5 Scenario, daily rainfall at most sites (63%) is projected to shift towards larger values. For the early 21st century (2016–2035), precipitation in the central basin increases, yet decreases occur over the middle reaches of the Yangtze River as well as a part of its southeast area. For the late 21st century (2081–2100), the mean precipitation and extreme indices experience an overall increase except for a few southeast stations. The total precipitation in the lower reaches of the Yangtze River and in its south area is projected to increase from 7% at 1.5 °C global warming to 11% at 2 °C, while the intensity enhancement is more significant in southern and western sites of the domain. A clustering allows to regroup all SOM nodes into four distinct regimes. Such regional synoptic regimes show remarkable stability for future climate. The overall intensification of precipitation in future climate is linked to the occurrence-frequency rise of a wet regime which brings longitudinally closer the South Asia High (eastward extended) and the Western Pacific Subtropical High (westward extended), as well as the reduction of a dry pattern which makes the two atmospheric centers of action move away from each other.  相似文献   

RELATIVE MOTION AND DEFORMATION OF PACIFIC PLATE FROM SPACE GEODESY     

Jin Shuanggen  Zhu Wenyao 《大地测量与地球动力学》2003,23(Z1)

1　IntroductionThroughoutthegeologicalhistory ,almostallthetectonicplateactivities,suchasearthquakes,volcaniceruption ,andmountainbuilding ,takeplaceatactiveplateboundaries.Forexample,approxi mately 90 percentoftheearthquakesoccuratactiveplateboundaries[1 - 4 ] ,andthehighestmountainsofTibetandAndesresultfromthecontinualcollisionbetweenIndiaandAsia ,NazcaandSouthAmericaplates,respectively .Aplateboundaryisafracturethatseparatesaplatefromanother;theneighboringplatesmoverelativetooneanotherin…  相似文献   

The surface cold water off Subei (Northern Jiangsu) in late spring and summer     

Pu Yongxiu 《中国海洋湖沼学报》1987,5(2):186-193

Every year during late spring and summer, a patch of surface cold water exists near the eastern side of the Subei shoal patch. The main cause of the cold water is the monthly southward migration and climbing up of the deep cold water from the western part of the southern Huanghai Sea. The existence of the deep ditches on the north side of the underwater delta off Subei controls the position of this cold water. Another patch of cold water is commonly observed southwest of Jizhou Island on the surface in the region 32^oN and 124^o–124.5^oE during late spring and summer. Based on analysis, this water comes mainly from the deep layers of the northwest area; its upwelling is related to the northward “impulsive” extension of the Taiwan Warm Current in the previous period, and its position is probably related to the underwater reef chain there.  相似文献   

试论区域的系统研究     

浦汉昕 《地理研究》1986,5(3):69-75

本文运用系统科学的观点与地理学的方法相结合研究区域,并以京津地区的研究为试点,探索区域系统研究的理论与方法。  相似文献   

The secular variation of inner zone high energy proton environment in the SAA     

XIE Lun  PU Zuyin  JIAO Weixin & FU suiyan Department of Geophysics  Peking University  Beijing  China 《中国科学D辑(英文版)》2005,48(12):2123-2130

The main portion of the inner radiation belt en-countered by spacecraft in low-Earth orbits (LEOs) is concentrated over the South Atlantic Anomaly (SAA) where satellites observed the highest particle flux. The anomaly arises from the Earth’s magnetic field being less intense in the region centered near the east of the Atlantic coast of South America. The trapped radiation belt particles therefore have their lowest mirroring altitudes over the center region of the SAA. Drift shells in t…  相似文献   

Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China   总被引：48，自引：0，他引：48  

YAO Tandong    WANG Youqing  LIU Shiying    PU Jianchen    SHEN Yongping & LU Anxin  .Institute of Tibetan Plateau Research  Chinese Academy of Sciences  Beijing  China  .Cold  Arid Regions Environmental  Engineering Research Institute  Chinese Academy of Sciences  Lanzhou  China 《中国科学D辑(英文版)》2004,47(12):1065-1075

There are about 46298 glaciers in the High Asiain China, the total glacial area is about 59406 km , andtotal glacial volume about 5590 km3. These glaciersmainly concentrate around the Himalayas Mountains,Nyainqentanglha Mountains, Kunlun Mountains,Karakoram Mountains and Tianshan Mountains. Theglaciers in the Tibetan Plateau are the major compo-nent of the glaciers in the High Asia in China. Theseglaciers extend north to the arid and desert regions,and become the main water resource in …  相似文献   

1960-2009年横断山区潜在蒸发量时空变化(英文)     

朱国锋  何元庆  蒲焘  王旭峰  贾文雄  李宗省  辛惠娟 《地理学报(英文版)》2012,22(1):71-85

Based on the meteorological data of 20 stations in the Hengduan Mountains region during 1961-2009, the annual and seasonal variation of potential evapotranspiration was analyzed in combination with the Penman-Monteith model. With the method of Spline interpolation under ArcGIS, the spatial distribution of potential evapotranspiration was presented to research the regional difference, and the correlation analysis was used to discuss the dominant factor affecting the potential evapotranspiration. The results indicated that the an-nual potential evapotranspiration showed a decreasing tendency since the 1960s, especially from the 1980s to 1990s, while it showed an increasing tendency since 2000. Regional potential evapotranspiration showed a rate of -0.17 mm a?1. Potential evapotranspiration in north, middle and south of the Hengduan Mountains exhibited decreasing trends over the studied period, and its regional trend was on the decline from southwest to northeast.  相似文献