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1.
ESTUARINE AND COASTAL SEDIMENTATION PROBLEMS 总被引:1,自引:0,他引:1
LeoC.VANRIJN 《国际泥沙研究》2005,20(1):39-51
This keynote lecture addresses engineering sedimentation problems in estuarine and coastal environments and practical solutions of these problems based on the results of field measurements, laboratory scale models and numerical models. The three most basic design rules are: (1) try to understand the physical system based on available field data; perform new field measurements if the existing field data set is not sufficient (do not reduce on the budget for field measurements); (2)try to estimate the morphological effects of engineering works based on simple methods (rules of thumb, simplified models, analogy models, i.e. comparison with similar cases elsewhere); and (3)use detailed models for fine-tuning and determination of uncertainties (sensitivity study trying to find the most influencial parameters). Engineering works should be designed in such a way that side effects (sand trapping, sand starvation, downdrift erosion) are minimum. Furthermore, engineering works should be designed and constructed or built in harmony rather than in conflict with nature. This ‘building with nature‘ approach requires a profound understanding of the sediment transport processes in morphological systems. 相似文献
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Grace S. BRUSH 《国际泥沙研究》1999,(2)
IHISTORICALRECORDSSoilerosioniscloselyrelatedtorainfallandgreatlyenhancedbydeforestationforagricultUreandurbansuburbandevelopment.Amongtheeffectsofsoilerosionarethelossoftopsoilandaconsequentdecreaseincropproductivity.Erodedsoilisalsodepositedintoaquaticsystems,thuslesseningwaterqualityandleadingtodepletionoftheaquaticfoodresource.Italsocausessiltationofwaterwaysmakingthemineffectiveforcommercialtransportaswellasincreasingtheriskoffloods.Theimpactofsedimenterosionanddepositiononhumanso… 相似文献
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Helmut M. HABERSACK Konrad BOGNER Josef SCHNEIDER Michael BRAUNER Department of Water Management Hydrology Hydraulic Engineering University of Agricultural Sciences Vienna Muthgasse Vienna Austria. Department of Forest and 《国际泥沙研究》2001,16(2)
1 INTRODUCTIONIn Anstria reservoirs are frequentiy multi-purpose schemes, being used for power generation, floodprotechon and for wate suPPly downstream. These reservoirs have some adVerse imPaCts on theenvironment around the reservoir and also on the dOwnstream pat:. in rivers with mean annual discharge above 30 m3ls about 36 % of the total length of l884 lQn isimpounded, and only 35% remains as free flowing sections (Muhar, l992),. flooding has been, and continues to be, a serious pr… 相似文献
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《国际泥沙研究》2014,(4)
正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study 相似文献
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《国际泥沙研究》2014,(4)
正Director:Shangfu Kuang,China Vice-directors:Chunhong Hu,China Duihu Ning,China Guangquan Liu,China The International Research and Training Center on Erosion and Sedimentation(IRTCES)was jointly set up by the Government of China and UNESCO on July 21,1984.It aims at the promotion of international exchange of knowledge and cooperation in the studies of erosion and 相似文献
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Su Chin CHEN 《国际泥沙研究》1998,(3)
RESERVOIRSEDIMENTATIONANDLANDUSEINTAIWANWUSHEHWATERSHEDSuChinCHEN1ABSTRACTWushehReservoirisagorgetypehydropowerReservoironW... 相似文献
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在对形变科研成果研究的基础上分析了地形变监测方法用于地震预报研究的现状和进展,对其效能作了肯定性评价。总结了这一研究领域20余年的得失和教训,并结合当前的体制和管理现状,改革开放对地震科研的新要求,提出了一系列改善本学科生存环境,增强其效益的建议。从自然科学和社会科学的不同视角,对本学科面临的阻力和困境进行了估计,最后展望了地壳形变在地震预报中的应用前景。 相似文献
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J. CASALI L. M. De SANTISTEBAN J. J. LOPEZ J. V. GIRALDEZ J. POESEN J. NACHTERGAELE M. GONI J. LOIZU M. A. CAMPO 《国际泥沙研究》2005,20(4):295-304
1 INTRODUCTION Erosion caused by ephemeral flows is a frequent phenomenon in nature and contributes to the shape of the landscape. This type of erosion may cause great soil losses in agricultural areas, which are quickly transferred to the watershed outlets through the rill and gully network (Bennett et al., 2000; Poesen et al., 2003). Concentrated flow erosion is controlled by the erodibility of surface materials, climate, soil use and management, and watershed topography. Several metho… 相似文献
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D.K. McCool 《国际泥沙研究》2000,(2)
h200l.llNTRODUCTI0NTheNorthwesternWheatandRangeRegi0n(NWax)(Austin,l98l),whichincludesportionsofIdaho,Oregon,andWashington,isoneofthem0stuniqueagriculturalregionsoftheUSA.Winterandspringsmallgrainsand0thercropsareproukcedonl0esss0ilsdepositedoverbasalt.TheloessvariesinboththicknessandtopograPhicfeatures.Someareashavesteepanddune-likeslopes,while0thershavel0ng,gentlesl0pes.Theregion,br0kenfromnativeprairielessthanl20yearsag0(Kaise,l96l)hassufferedseriousdegradationofthesoilresourcebyw… 相似文献
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1INTRODUCTIONInaneforttoprovideadequatefoodandfibreforthetemingpopulation,mostcountriesinthetropicshaveopeneduptheirprotectiv... 相似文献
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XU Guobin Senior Research Engineer Tianjin Institute of Hydroelectric Investigation Design Research Ministry of Water Resources. Dongting Road Hexi District Tianjin P R. China. BAI Shilu Senior Research Engineer Tianjin Institute o 《国际泥沙研究》1997,(3)
I.INTRODUCTIONReseri,oirsonoverloadedriverswillreachthestateofrelativeequilibriumwithcontinuousdevelopmentofsedimentation.Insuchcase,thereisdePOsitinfrontofthedam.Thereforethesiltpressureonthedambodyisconsiderablylarge.Sedimentationelevationinfrontofthedamisoneofthefactorsofcalculatingthesiltpressure.Inaddition,tokeeplong-termworkingstorageinreservoif,itisnecessarytoinstallbottomoutlets.Asthereisapressureconduitinfrontoftheoperatinggateofthebottomoutlet,thesedimelltenteredtheconduitwill… 相似文献
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1 BACKGROUND The Kankakee River, which straddles the States of Indiana and Illinois in the Midwest, is shown in Fig. 1. This figure also shows the dividing line between these two states and the streamgaging and few sediment gaging stations in the basin. The main stem of the river in Indiana was channelized, thus bypassing numerous oxbows, meanders, side channels, etc., that existed before the 1890s. Before channelization in Indiana, the river essentially flowed through a wetland/mar… 相似文献
13.
FORMATION AND EROSION PROCESSES OF THE LOESS PLATEAU 总被引:2,自引:0,他引:2
IPROCESSANDZONINGOFLOESSACCUMULATIONLoessisatypicalkindofaeoliansediment,theprocessesofitsgeomorphicformationcanbesummarizedasfollows.l.lWell-distributedDustFalloutfromHighAltitudeThedustisdefinedasthefineparticles(<0.1mm)whichcanbeliftedandcarriedupasdustcloudsintheaiLIftheoriginallandsurfaceofaregionisanevenhighlandsurroundedbyriversandgullies,thefallingdustremainedonthesurfaceofthisevenhighland,butthedustfallingonslopesoftheriverandgullieswastransportedoutoftheregion.Onthet… 相似文献
14.
ON SOME KEY SEDIMENTATION PROBLEMS OF THREE GORGES PROJECT (TGP) 总被引:1,自引:0,他引:1
Lin Bingnan Dou Guoren Xie Jianheng Dai Dingzhong Chen Jisheng Tang Richang Zhang Ren 《国际泥沙研究》1989,(1)
I. INTRODUCTIONThe Three Gorges Project (TGP) being planned is to be located on the Yangtze River at Sandouplug, 44 km upstream of Yichang (Fig. l). A scheme studied in the feasibility stage has the crest ofthe dam placed at 185 m with a maximums height o… 相似文献
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D. K. MCCOOL J. D. WILLIAMS 《国际泥沙研究》2005,20(3):202-210
Hydrology of the Northwestern Wheat and Range Region (NWRR) of the Pacific Northwest USA is dominated by winter events. Fifty-five to sixty-five percent of the precipitation occurs from November through March, and formation of impermeable frost, intensified by excessive tillage and tillage pans, has long been a major factor in rill and gully formation in the region. Saturated zones can form above tillage pans, freeze solid, and significantly reduce infiltration. Frost heaved surface soils thaw and weaken with warming temperatures or rain. Under these conditions, runoff from rain or snowmelt or a combination of the two is inevitable, concentrating in rills and channels, and carrying with it the loosened soil. Slopes are frequently quite steep and there may be little deposition above the toe slope. Classical over-fall head-cut gullies are uncommon. Concentrated flow channels form because of collection of water from impervious areas such as conventionally tilled fall seeded small grains and bare grass seed fields. In some soils, gullies are created by seepage from saturated layers above permanent restrictive layers in the soil. Gullies can also result from terrace failures due to rodent burrows and low compaction at the time of construction. In naturally unconsolidated soil, rodent activity can lead to piping failures that remove large quantities of subsurface soil and can become gullies. Rill measurements on conventionally tilled fields in Oregon, Washington, and Idaho were used to determine coefficients for relationships between slope length and steepness and size of rills. This paper describes these studies and the results as well as analysis of long-term erosion and weather records from southeastern Washington. 相似文献
18.
NUMERICALMODELINGOFSILTSEDIMENTATIONANDRELEVANTENGINEERINGPROBLEMSQingcunZENG;DengjianGUO;ZhuoLIUandJiangZHU2(1MelnberofChine... 相似文献
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TWO-DIMENSIONAL MATHEMATICAL MODEL FOR STUDYING EROSION AND SEDIMENTATION OF A WANDERING STRETCH IN THE LOWER YELLOW RIVER 总被引:1,自引:0,他引:1
ZHANG Shiqir 《国际泥沙研究》1994,(3)
TWO-DIMENSIONALMATHEMATICALMODELFORSTUDYINGEROSIONANDSEDIMENTATIONOFAWANDERINGSTRETCHINTHELOWERYELLOWRIVER¥ZHANGShiqir(Senior... 相似文献
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Chi-hua HUANG Fenli ZHENG 《国际泥沙研究》2005,20(4):350-357
During the past 50 years, many research efforts have been invested in understanding soil erosion process and development of erosion prediction models at various scales. This paper briefly introduces the erosion process and prediction model development in the USA. Especially, this paper focuses on discussing potential impacts of the erosion process on erosion model development, and future directions of the soil erosion process research and process- based model development. 1 DEVELOPMENT O… 相似文献