“全面禁止核试验条约”的数据宝藏

一个旨在检测核爆炸的传感器台网可以帮助科学家研究从鲸鱼到火山的一切事情。但它们被允许使用吗?     

DEVELOPMENT OF A DECISION SUPPORT SYSTEM FOR MANAGING PESTICIDE LOSSES IN AGRICULTURAL WATERSHEDS

1 INTRODUCTION Agricultural use of pesticides has been recognized as one of the important non-point pollution sources in the world, and the pesticide application to agricultural lands has led to large amounts of residues discharged into surface water through runoff (Leonard, 1990). There have been growing concerns about the fate and transport of pesticides in agricultural lands, due to the associated adverse impacts on water environment and human health (Agassi et al., 1995; Ng and Clegg…     

SOIL CONSERVATION EFFICIENCY OF DIFFERENT MODELS CONVERTING FROM STEEP FARMING SLOPE PLOTS IN YA''''AN, SICHUAN, CHINA

Converting farming slope land into artificial forestland or grassland is a major measure of soil/water conservation. Five conversion practices, namely, 1) a control plot still tilled with a crop (maize), 2) a folder grass-growing plot seeded with Lolium perenne , 3) a young alder tree-growing plot, 4) a pear orchard plot and 5)a bamboo plot intercropped with folder grass, were monitored to compare the soil conservation efficiency of those changes in Ya'an, Sichuan for 3 years between September 1998 and August 2001. Results showed that the 5 designed converting models functioned differently in erosion control. The most effective model was bamboo groves intercropped with folder grass (Lolium perenne). The folder grass (Lolium perenne) growing model was more effective than the pure pear orchard model. The least effective model was the young alder tree-growing slope, which was even less effective than the control (a slope without converted cultivation). Meanwhile, changes in the soil's physical properties r     

西藏安多北断裂晚第四纪活动的基本特征

安多北断裂是青藏高原中部安多—错那盆地的北边界断裂(图1)。安多—错那盆地是青藏高原中部当雄—羊八井活动构造带北端的一个断陷盆地,盆地的北缘和南东缘分别为安多北断裂、安多南断裂和错那东断裂,这些断裂均为全新世活动断裂,安多北断裂和安多南断裂控制形成安多盆地,错那断裂控制形成错那盆地。安多盆地总体呈NNE走向,长约80km,南北宽约6～15km,盆地面的海拔高程为4580～4700m,呈东北部高、西南部低的趋势。以前的活动构造研究多集中在当雄—羊八井活动构造带的主体部分,如对念青     

MODELING STUDY ON SEDIMENTATION CONFIGURATION IN FRONT OF THE DAM AND IN THE PRESSURE CONDUIT OF BOTTOM OUTLETS BY FLUME EXPERIMENT

I.INTRODUCTIONReseri,oirsonoverloadedriverswillreachthestateofrelativeequilibriumwithcontinuousdevelopmentofsedimentation.Insuchcase,thereisdePOsitinfrontofthedam.Thereforethesiltpressureonthedambodyisconsiderablylarge.Sedimentationelevationinfrontofthedamisoneofthefactorsofcalculatingthesiltpressure.Inaddition,tokeeplong-termworkingstorageinreservoif,itisnecessarytoinstallbottomoutlets.Asthereisapressureconduitinfrontoftheoperatinggateofthebottomoutlet,thesedimelltenteredtheconduitwill…     

地壳磁化强度模型和居里等温面

利用卫星观测的长波磁异常，用等效偶极源方法推导了中国地区的视磁化强度分布．因卫星的高度远大于磁性地壳的厚度，将视磁化强度转换成磁化强度的垂直积分，它代表地壳内磁性物质的区域变化，利用视磁化强度与地表热流相应关系，计算了中国的新疆和东部一些地区居里等温面的深度．新疆地区的居里面深度为35-50km，其分布形态与塔里木盆地和准噶尔盆地的地貌比较相似；中国东部一些地区居里面深度在20-40km之间，与一些作者用航磁等数据得到的居里深度十分接近．     

Crust-Mantle Electrical Structure in the Area along the Yadong-Burn Co Profile

1.IntroductionUntilnowTibetisstillthearchetypalregionwithcontinentalcollisiongoingoninit,henceitisanidealnaturallaboratoryforstudyingthegeologicevolutionofintracontinentalorogenicbeltandthecrust-mantledeepprocesses,aswellastheinteractionbetweenthemandthesupracrustalmovements.Forthisreason,forseveraldecadesgeologistsandgeophysicistsfromvariouscountrieshavemadeunremittingeffortsinthisregiontoprobeintotheoriginandprocessoftheplateauformation,withavarietyofcognitionsproposed.TheCMPresultsoftheSi…     

SEDIMENT TRANSPORT MODEL OF A WATERSHED

ChinaisoneOfthecountrieswhichsufferfromthemostserioussoilerosionintheworld,andthehillyandgullyareasof~PlateauinthemiddlereachesOftheYellowRiverarethemostseriouserosionareainChina.Inthisarea,themainerosivefactorsarerainfallandrunoff.Sometimes,thesedimentyieldinasinglefloodeventcanbe40%oftheannualsedimentload.Therefore,itisveryimPOrtanttostudytheyieldandgraphOfSedimentOfsinglefindevent.Forthispn~,thispaperiswritten.AInongsedimentmodelsforsinglefloodevent,moreandmoreattentionwaspaidtOunitse…