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ＴｈｅＳｏｎｇｈｕａＲｉｖｅｒ，ｏｎｅｏｆｔｈｅｍａｊｏｒｒｉｖｅｒｓｉｎＮｏｒｔｈｅａｓｔＣｈｉｎａ，ｈａｓｔｗｏｓｏｕｒｃｅｓ：ｔｈｅｎｏｒｔｈｓｏｕｒｃｅｉｓｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒａｎｄｔｈｅｓｏｕｔｈｓｏｕｒｃｅｉｓｔｈｅＳｅｃｏｎｄＳｏｎｇｈｕａＲｉｖｅｒ．ＴｈｅｔｒｕｎｋｓｔｒｅａｍｏｆｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒ，ｒｉｓｉｎｇａｔｔｈｅｓｏｕｔｈｅｒｎｆｏｏｔｏｆｔｈｅＹｉｌｅｈｕｌｉＭｏｕｎｔａｉｎ，ｉｓ１３７０ｋｍｌｏｎｇａｎｄｉｔｓｗａｔｅｒｓｈｅｄａｒｅａｉｓ… 相似文献
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全国山洪灾害调查评价成果及规律初探 总被引：2，自引：0，他引：2
山洪灾害调查评价是1949年来水利行业最大的非工程措施项目,是规模最大的全国性防灾减灾基础信息普查工程,历时4年,涉及全国30个省305个市2138个防治县（区）,国土面积755万km2,人口近9亿。运用普查、详查、外业测量、分析计算等多种手段,掌握了中国山洪灾害防治区范围、人员分布、下垫面条件、社会经济、历史山洪灾害等基本情况,科学分析了山丘区小流域的暴雨洪水特性,评价了现状防洪能力,计算了预警指标,划定了危险区,为山洪灾害预警预报和应急救援决策提供了基础信息支撑。本文系统介绍了全国山洪灾害调查评价的核心要点,综述了调查评价成果,归纳了调查评价成果要素类型,揭示了全国山洪灾害防治区、人口、历史山洪灾害事件与预警能力的空间分布一致性,即山洪灾害各要素集中分布于青藏高原-四川盆地过渡带、川滇交界地区、黄土高原区、东部沿海地区及华北等地区,最后初步探讨了该成果的应用前景。全国山洪灾害调查评价成果将为中国山洪灾害监测预警预报体系建设及防灾减灾能力提升提供丰富的基础数据支撑。 相似文献
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THE SIMULATED STORAGE CAPACITY OF FLOOD AND WATERLOGGING IN THE TYPICAL AGRICULTURAL REGION IN JIANGHAN PLAIN 总被引：2，自引：0，他引：2
１ＩＮＴＲＯＤＵＣＴＩＯＮＪｉａｎｇｈａｎＰｌａｉｎｉｓｏｎｅｏｆｔｈｅｉｍｐｏｒｔａｎｔｂａｓｅｓｏｆＣｈｉｎａ′ｓａｇｒｉｃｕｌｔｕｒａｌｐｒｏｄｕｃｔｉｖｉｔｙｌｏｃａｔｅｄｉｎｔｈｅｍｉｄｄｌｅＣｈａｎｇｊｉａｎｇＲｉｖｅｒｖａｌｌｅｙｏｆｃｅｎｔｒａｌＣｈｉｎａ．ＴｈｅＪｉａｎｇｈａｎｐｌａｉｎａｐｐｒｏｘｉｍａｔｅｌｙ６．６×１０４ｋｍ２ｉｎａｒｅａａｎｄｏｖｅｒ３０ｍｉｌｌｉｏｎｉｎｐｏｐｕｌａｔｉｏｎｉｓｔｈｅｒｅｎｏｗｎｅｄ“ｃｏｕｎｔｒｙｏｆｆｉｓｈａｎｄｒｉｃｅ＂ｉｎ… 相似文献
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This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 210 Pb dating and was sampled at 1–2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size(14.32–96.39 μm) contribution30%, Zr/Rb ratio1.5, and magnetic susceptibility16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods. 相似文献
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1 INTRODUCTION The Ussuri / Wusuli River watershed is located in the southeast part of Heilongjiang Province of China, which joins remote regions of Russia. The watershed consists of approximately 26 000 000 ha, which is about two thirds of the watershed ecosystem in Russia, one third in China. The Ussuri River forms part of the border between Russia and China, the shared border stretches more than 1100 km. Khanka/Xingkai Lake lies within both China and Russia. Its total area … 相似文献
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陈海龙 《中国地理科学(英文版)》1992,2(2):145-158
According to historical records, there are 264 drought and flood years, occurred in the upper and middle reaches of the Changjiang (Yangtze) River during last 1020 years from 961 to 1980. The evolutionary law and developing trend of drought and flood years are studied. The distribution of drought and flood years are non-uniform and the dry and flood seasons in a year are concentrated. At the angle of monsoon circulation, at present the climate in the upper and middle reaches of the Changjiang River is just in the late stage of frequent drought period and the early stage of least flood period. In addition, the cycle of drought and flood and the feature of drought and flood occurred in the upper, middle and lower reaches of the Changjiang River are analyzed. It shows that the short period less than 10 years is in the majority, and the drought and flood occurred most frequently in the middle and lower reaches of the Changjiang River. 相似文献
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利用遥感对地观测技术对2020年夏季鄱阳湖地区发生的洪水灾情进行评估和分析,分别选取Landsat 8卫星4月和 Sentinel-1A雷达卫星7月的影像作为洪水发生前、后的影像,利用遥感专题信息提取、随机森林分类和变化检测技术揭示洪水淹没范围,以及被淹没的主要土地覆盖类型面积,同时结合水文气象和地形数据进行灾情和受灾原因分析。研究结果表明,鄱阳湖2020年洪灾的淹没面积为1961.95 km2,共造成区内110.83 km2建筑用地、760.54 km2耕地、71.59 km2林地、992.02 km2草地和26.97 km2裸地被淹,其中尤以鄱阳县受灾最为严重,其总受灾面积达到514 km2,其次为新建区与余干县,分别达到了330 km2和310 km2。持续2个月的强降雨使得鄱阳湖流域的水位超过了其1998年特大洪水的水位,加上长江水倒灌,湖区地势北高南低,积水不能及时排出,圩堤决口等诸多水文气象和地形因素造成了此次鄱阳湖的特大洪灾。 相似文献
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DISTRIBUTION OF THE MAIN CROP GERMPLASM RESOURCES IN CHINA 总被引：1，自引：0，他引：1
Cropgermplasmresourcesaretheindispensablematerialbaseforcropbreedingandagriculturalproduction.Theresearchondistributionofcropgermplasmr~urcesisofgreatimportanceinstudyingonorigin,evolutionandclassificationofcrops,expeditingandcollectinggermplasm,ascertainingofcentersofdiversity,protectinggermplasmr~urcesandmakingagriculturalproductiondivision.Since1949,researchesofexploration,collection,preservation,cha-racterizationandevaluationofcropgermplasmresourceshavebeendoneinChina.Atpresent,thenational… 相似文献
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文章概述了漓江流域水环境现状，分析了存在的主要问题，阐明了流域水灾频繁、水环境污染的成因，指出了流域森林结构欠合理，调蓄能力不足，导致了流域洪涝、干旱频繁，枯水期长，水资源短缺；流域生活与生产排污，造成枯水期水污染。因而需进行深入的科学研究、绿化、兴修水利工程、实施节水技术、严格管理、科学调配水资源等综合举措，实现流域的可持续发展。 相似文献
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夏宜铮 《中国地理科学(英文版)》1994,4(1):8-18
ＴＨＥＥＦＦＥＣＴＳＯＦＴＨＥＴＨＲＥＥＧＯＲＧＥＳＰＲＯＪＥＣＴＯＮＥＣＯＬＯＧＹＡＮＤＥＮＶＩＲＯＮＭＥＮＴＸｉａＹｉｃｈｅｎｇ（夏宜铮）（ＩｎｓｔｉｔｕｔｅｏｆＨｙｄｒｏｂｉｏｌｏｇｙ，ｔｈｅＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｗ... 相似文献
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WISE EXPLOITATION OF NEWLY GROWING LAND RESOURCES——An Assessment on Land—use Change of Chongming Island Using GIS 总被引：4，自引：1，他引：3
Chongming Island, the third largest island in China and the largest alluvial island in the world, is situated in the north
of Shanghai Municipality at the mouth of the Changjiang (Yangtze) River. Along the fertile and prosperous sea coast there
are a total area of over 120×103ha, with a population of 735 000, accruing some 500ha of new tidal land resources come from silt, sand and mud carried by
the Changjiang River every year, extending about 140m per year. This dynamic process of alluvial growth has run for some 1500
years. Mudflat on Chongming Island at the mouth of the Changjiang River is a resting ground for migratory birds and host more
than a hundred species, including rare cranes and geese. But the local people keep reclaiming the tidal land for economic
development. Obviously, it is crucial to have a well-concerted plan for future exploitation. In this study, we attempted to
investigate the status changes of land use and wild life habitats on Chongming Island in recent 10 years, and then analyzed
different human activities and their effects on wild life habitats using satellite image data (1990, 1997 and 2000) as well
as field survey. Based on the analysis, this study explored the relationships between island growth and land use/cover change
(LUCC), predicted what the habitat would be like in the future and tried to find more effective use of this new growing resource.
At last, this study provided some preliminary management plans for Chongming Island that will coordinate the development of
local economies and the conservation of wild life and their habitats.
Foundation item: Supported by WWF (World Wildlife Fund) China Program (CN0079.08).
Biography: ZHAO Bin (1969 - ), male, a native of Hubei Province, Ph. D., specialized in landscape ecology and biodiversity
information system management. 相似文献
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Floodplains are important and distinctive ecosystems around the world, and the recruitment of ichthyoplankton from river to floodplain lakes is crucial to maintain this unique ecosystem. However,this process has not been well documented. In this study, ichthyoplankton were sampled to investigate the details of ichthyoplankton recruitment from the Changjiang(Yangtze) River to the Dongting Lake via a floodway channel, the Songzi River, from May to July in 2013 and 2014. During the study period, 41 species of eggs and larvae were sampled. Among the samples, 16 were river-lake migratory species(RL), representing23.5% of the species in the Dongting Lake. In 2013, an estimated 130 million eggs and 3 180 million larvae drifted through the sampling section, and in 2014, an estimated 1 060 million eggs and 1 040 million larvae drifted through the sampling section. The amount of eggs and larvae of RL reached 3 210 million in 2013 and 1 850 million in 2014, respectively. These results demonstrated the importance of ichthyoplankton recruitment from the river to the lake, as species diversity will decrease sharply without this recruitment.Canonical correspondence analysis(CCA) showed that water temperature and water flow are the two most important factors influencing the spawning activities of fish. To maintain the high fish diversity in the Changjiang floodplain, we suggest to irrigate the channel to increase water discharge and increase the transport of ichthyoplankton from the Changjiang mainstream into the Dongting Lake. 相似文献
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The Chinese people began to research the main source of the Changjiang (Yangtze) River 2,400 years ago. Limited by the scientific
level, they did not discover it.
The Tuotuo River was determined as the main source of the Changjiang River in the 1970s. However, this was not correct, because
when comparing the length of the Tuotuo River with the Dam River, the glacier length at the headwaters was added to the Tuotuo
River, resulting in that the Tuotuo River is 1 km longer than the Dam River, keeping in mind that the glacier can not be regarded
as part of the river.
In the summer of 1986, we investigated the source of the Changjiang River, we accurately measured the length of both the Tuotuo
and Dam rivers, we discovered that the Dam River was 353.1 km long, and the Tuotuo River was 346.3 km long, the Dam River
thus being 6.8 km longer than the Tuotuo River. The discharge of the Dam River is 196.18 m3/sec., 2.6 times as large as that of the Tuotuo River, that of the Tuotuo River is 75.10 m3/ sec. The drainage area of the Dam River is 1.8 times as larger as that of the Tuotuo River; the drainage area of the Dam
River is 30,715.7 km2, the Tuotuo River is 16,691.0 km2.
Through synthetic analysis of the factors mentioned above, we came to the conclusion that the main source of the Changjiang
River is the Dam River instead of the Tuotuo River. 相似文献
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Geometrical feature analysis and disaster assessment of the Xinmo landslide based on remote sensing data 总被引：5，自引：3，他引：2
Jian-rong Fan Xi-yu Zhang Feng-huan Su Yong-gang Ge Paolo Tarolli Zheng-yin Yang Chao Zeng Zhen Zeng 《山地科学学报》2017,14(9):1677-1688
At 5:39 am on June 24, 2017, a landslide occurred in the village of Xinmo in Maoxian County, Aba Tibet and Qiang Autonomous Prefecture(Sichuan Province, Southwest China). On June 25, aerial images were acquired from an unmanned aerial vehicle(UAV), and a digital elevation model(DEM) was processed. Landslide geometrical features were then analyzed. These are the front and rear edge elevation, accumulation area and horizontal sliding distance. Then, the volume and the spatial distribution of the thickness of the deposit were calculated from the difference between the DEM available before the landslide, and the UAV-derived DEM collected after the landslide. Also, the disaster was assessed using high-resolution satellite images acquired before the landslide. These include Quick Bird, Pleiades-1 and GF-2 images with spatial resolutions of 0.65 m, 0.70 m, and 0.80 m, respectively, and the aerial images acquired from the UAV after the landslide with a spatial resolution of 0.1 m. According to the analysis, the area of the landslide was 1.62 km2, and the volume of the landslide was 7.70 ± 1.46 million m3. The average thickness of the landslide accumulation was approximately 8 m. The landslide destroyed a total of 103 buildings. The area of destroyed farmlands was 2.53 ha, and the orchard area was reduced by 28.67 ha. A 2-km section of Songpinggou River was blocked and a 2.1-km section of township road No. 104 was buried. Constrained by the terrain conditions, densely populated and more economically developed areas in the upper reaches of the Minjiang River basin are mainly located in the bottom of the valleys. This is a dangerous area regarding landslide, debris flow and flash flood events Therefore, in mountainous, high-risk disaster areas, it is important to carefully select residential sites to avoid a large number of casualties. 相似文献
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YANG Gui-shan 《中国地理科学(英文版)》2000,10(2):97-104
TheChangiiangRiverisrichinfreshwaterandwaterpowerresources,themeanrunoffandwaterpoweroftheriverareabout37%and52%respectivelyoftotalonesofChina.Inaddition,theChanaiiangRiverhastheimmensenavigationpotentialandvaluableshorelineresources,thenavigablelengthreaches364okmandtheallshorelinelengthisabout6OOokmfromYihinCitytotheestuary.Moreover,theChangiiangRiver,withtheadvantagesofsuitablelocationandbroadhinterland,crossesEast,MiddleandWestEco-nomicZonewithdifferenteconomiclevelsofChina,soitsuniq… 相似文献
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强暴雨淹没耕地形成灾害的同时,对耕地作物的生长也产生着极大的影响,而暴雨灾害对耕地作物生长的影响是一个渐变过程,需要由时空动态的观测进行监测。多源卫星遥感观测技术具有捕捉地面瞬间状态和刻画过程的优势。论文利用Terra/MODIS、Landsat和Sentinel卫星观测数据,挖掘多源卫星遥感观测数据,提出了一种利用NDVI变化的特征值进行灾情动态信息提取方法;并以2016年发生暴雨灾害的巢湖地区为实验区进行了方法的应用和讨论。结果表明,基于MODIS多时相NDVI变化结果提取的信息能够获得受灾害影响开始时期和持续时长等丰富的时空动态信息,根据这些信息可以统计得出大范围区域中受灾害影响的面积。另外,结合利用30 m和10 m的Landsat和Sentinel观测数据提取的水淹区,可为在暴雨致灾范围方面提供准确的参考信息。多源遥感作为评估灾情信息的依据之一,其获取的灾情动态信息能够为灾后耕地的恢复情况以及国家灾后损失评估和救助决策提供科学的数据依据。 相似文献
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According to the drought and waterlogging disaster statistics over the last 30 years (1950-1979), the annual average area suffering from drought was about 300 million mu (1 mu= 1/ 15 ha) in the whole country, among which about 100 million mu were disastrous areas where the output reduced more than 30%. and the annual lost grains totalled about 5 billion kg. The waterlogging disaster was less than drought disaster. The area suffering from waterlogging was about 100 million mu, among which 60 million mu were disastrous. Drought and waterlogging disasters affect directly the development of the national economy. So it is important to study drought and waterlogging variations, especially the drought and waterlogging variation laws of the areas where the disasters frequently occur.The historical literatures and recent observation data reveal the fact that there existed drought and waterlogging variations. For example, the occurrence frequency of the outstanding and severe drought years in north China is highe 相似文献
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Outburst risk of barrier lakes in Sichuan,China 总被引：2，自引：1，他引：1
34 barrier lakes induced by earthquake have been formed by wedged debris on the river channels after a massive earthquake happening on May 12 in Sichuan, China. Among them, the Tangjiashan Barrier Lake is the largest one. It faces very urgent risk of dam breaking when water level reaches the top and begins overflow in case of storm rainfalls and continually aftershocks, threatening already devastated cities and villages with about 1.5 million people downstream. The outburst of a similar barrier lake occurred in the Minjiang River in 1933, causing a catastrophic flood. Risk analysis indicates that not all barrier lakes are highly dangerous. Only those lakes with very high dams and water to be filled up in short period need to be dealt with immediately. 相似文献