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植被高光谱特征分析及其病害信息提取研究 总被引：4，自引：0，他引：4
高光谱(hyperspectral)遥感是20世纪末地球观测系统中最重要的技术突破之一。根据植被高光谱数据的植被冠层光谱反射特征和诊断性光谱吸收特征,利用光谱连续统去除法,探讨光谱一阶微分反射比(FDR)和从连续统去除的光谱吸收特征中获得的波段深度(BD)、连续统去除后微分反射比(CRDR)、波段深度比(BDR)和归一化波段深度指数(NBDI)等光谱特征参量。结合多时相的条锈病小麦PHI航空高光谱影像,分析条锈病对小麦光谱的影响及其光谱特征,并运用光谱特征参量和波谱角制图(SAM)技术监测和识别小麦条锈病。 相似文献
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抛光花岗岩的二向反射比与偏振度的波谱关系 总被引：1，自引：0，他引：1
传统遥感定义双向反射率分布函数(BRDF)的概念,用以表达目标物空间反射的多角度分布特征,但其测量多偏重于单波长的微波及激光。偏振伴随多角度探测而生,蕴涵了目标物的自身特性。该文就城市常见地物——抛光的花岗岩,分别测量了其在350～2 500nm范围内的二向反射比和偏振度的波谱,分析并比较了两者波谱随探测角度的变化规律,并从定义上分析了两者的波谱关系,发现其随探测天顶角及方位角的变化规律一致,而且二向反射比和偏振度的波谱在一定程度上呈反比关系。 相似文献
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水分胁迫条件下棉花生理变化及其高光谱响应分析 总被引：19，自引：4，他引：15
利用ASD地物光谱仪,测定水分胁迫条件下棉花不同生育时期内叶片的光谱反射率,应用微分技术处理棉花的反射光谱,并结合棉花叶面积指数(LAI)、叶绿素(a b)含量(Chlt)、叶片全氮(TN)含量等生物参数进行分析,研究棉花水分胁迫情况下的高光谱特征,结果表明,一阶微分光谱720nm波段的数值与LAI的正相关(R=0．7656);750nm处一阶微分值与叶绿素含量呈显著正相关关系(R=0．7774);微分光谱690nm～740nm数值积分面积与TN含量呈正相关(R=0．7669),采用比值反射率对反射光谱1300nm～1500nm波段范围内最小值与棉花叶片的含水量作相关分析,达到极显著水平(R^2=0．8298),验证了一阶微分光谱数据与棉花的生理参数有很好的相关性,可见光和近红外波段光谱反射率能够反映出棉花生长发育的动态特征;证明了棉花的花铃期是高光谱遥感对棉花长势和生理参数定量诊断的最佳时期。本研究通过建立一系列线性光谱模型对棉花生理参数进行估测,为基于高光谱数据的棉花生长模型和棉花长势的遥感监测提供了理论依据。 相似文献
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利用可见光/近红外反射光谱估算土壤总氮含量的实验研究 总被引：25，自引：0，他引：25
利用土壤的室内反射率光谱，探讨土壤氮元素的高光谱机理。利用土壤光谱各吸收带的特征参数与总氮含量进行逐步回归运算，确定与氮元素关系比较密切的几个吸收带。计算出这几个特征吸收带内土壤反射率的变化形式：一阶导数(FDR)、倒数(1/R)、倒数之对数(log(1/R))、波段深度(Depth)，并与总氮含量进行逐步回归分析，得到比较理想的结果：建模样本的Ra^2(修正的判定系数)分别为0．789、0．753、0．736、0．699，验证样本的Ra^2分别为0．759、0．468、0．794、0．725。可见土壤的反射率光谱与氮元素含量之间存在比较明显的相关性，可见光／近红外反射光谱具有快速估算土壤中氮元素含量的潜力。 相似文献
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塔里木河中游典型绿洲盐渍化土壤的反射光谱特征 总被引：2，自引：0，他引：2
研究盐渍化土壤的光谱特性是利用遥感技术实现在区域尺度上进行土壤盐渍化监测和评价的工作基础, 是建立地面数据和遥感数据关系的桥梁。本文以塔里木河中游典型绿洲--渭干河-库车河三角洲绿洲为研究对象, 采用光谱学技术以及多元统计相结合的方法, 研究干旱区典型绿洲盐渍化土壤的反射光谱特征。首先, 对光谱数据进行预处理(去噪、剔除水分吸收波段), 以便消除仪器本身噪声及外界条件的影响, 并且计算了部分盐渍地样本的光谱吸收特征参数, 说明相同程度的盐渍化土壤具有相似的吸收特征;其次, 研究盐渍化土壤的反射光谱与盐分因子(八大离子、电导率(EC)、含盐量(salt content)、pH、总溶解固体(TDS)等) 之间的关系, 并选择具有代表性的盐分因子与野外实测光谱数据建立定量回归模型, 通过多元线性回归分析得出含盐量、SO42-、TDS、EC与原始光谱数据的相关性分别是0.746、0.908、0.798 和0.933, 达到了理想的效果。本研究对于干旱区典型绿洲盐渍土的光谱特征研究有着重要指示意义, 为发展和完善中国盐渍土理化特征的可见光-近红外反射光谱分析理论奠定科学积累, 并进一步为干旱区土壤盐渍化、沙漠化灾害等环境恶化问题的解决提供新的科学技术手段。 相似文献
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黄壁庄水库水质参数遥感反演研究 总被引：6，自引：0，他引：6
以石家庄市黄壁庄水库为研究对象,利用ASD FieldSpec Pro野外光谱辐射计进行反射光谱测量和同步水质采样分析,应用高光谱技术阐释了水质参数(SS、COD、TN、TP)与光谱反射率的关系,为今后利用星载高光谱传感器对黄壁庄水库乃至我国北方内陆水体水质参数进行大面积反演提供理论基础。在分析水库水体反射光谱特征的基础上,运用微分光谱技术和统计相关方法直接分析、诊断各水质参数的敏感波段,并建立线性估算模型,确定研究区SS、COD、TN、TP的敏感波段分别为715 nm7、04 nm、595 nm8、73 nm。 相似文献
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以花芽分化期荔枝为例，分析了荔枝冠层叶片养分质量分数的空间分布差异；选用18种光谱变量，研究了荔枝不同冠层叶片养分质量分数与光谱变量的关系及其对无人机多光谱遥感监测模型的影响。结果表明：荔枝不同冠层叶片的氮、钾质量分数随冠层高度降低而明显提高；冠层中、上层叶片氮质量分数与无人机正射数据计算的类胡萝卜素反射指数（CRI）相关性最高（r＝0.86，p＜0.01）；冠层中、下层叶片钾质量分数与无人机正射数据的光谱变量显著相关，且与标准绿波段（NG）指数的相关程度最高（r＝-0.83，p＜0.01）。荔枝冠层叶片养分质量分数空间变化对基于垂直观测遥感数据建立的叶片养分质量分数估算模型精度有影响，无人机多光谱数据具有估算荔枝叶片氮、钾质量分数变化的潜力，但估算精度与冠层高度有关。 相似文献
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塔里木河流域中游渭干河-库车河绿洲盐渍土水盐信息光谱特征研究 总被引：2，自引：0，他引：2
土壤水分、盐分时空变异强,是影响土壤光谱特征的两个重要因素。土壤水分与盐分之间的关系以及土壤水分、盐分与土壤光谱特征间的关系直接关系到利用遥感光谱信息监测土壤盐渍化的精度。该文运用多元统计学及可见光-近红外反射光谱分析方法对2010年10月渭干河-库车河三角洲绿洲盐渍土水分、盐分数据和盐渍土野外光谱数据进行分析,探讨该绿洲盐渍土表层(0～10cm)水盐信息与野外光谱特征间的关系。结果表明:1)土壤水分和土壤电导率可用Cubic曲线拟合,相关系数R=0.8503,土壤盐分和土壤电导率也可用Cubic曲线拟合,相关系数R=0.842,但土壤水分与盐分之间的显著性较弱,相关系数R=0.74。2)与原始野外光谱相比,包络线消除后光谱波段与土壤水分和土壤电导率之间的Pearson相关性都有不同程度的提高,利用包络线消除法后的波段分别建立盐渍土土壤水分、土壤电导率后向回归预测方程,为动态水盐条件下的盐渍土遥感监测提供了理论依据。 相似文献
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基于多波段分析的无阈值自动光谱角制图分类法 总被引：2，自引：0，他引：2
对光谱角制图分类法进行改进,主要方法是在原影像的6个波段基础上,加入了K-L变换的前3个波段、K-T变换的3个波段(亮度、绿度和湿度)以及NDVI(归一化植被指数)信息将图像波段数增加至13个,增强了地物之间的光谱区分度(即类间方差);得到光谱角度图像后,提出一种无需阈值的地类确定方法,减少了人工参与,提高了判别精度和处理效率。 相似文献
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《The Professional geographer》1988,40(4):471-499
Books reviewed in this article: USA, Eine Geographische Landeskunde , Vol. I, Der Grossraum in Strukturellem, Wandel, 3rd Ed. Helmut Blume . Introduction to Remote Sensing . James B. Campbell . The Sounds of People and Places: Readings in the Geography of American Folk and Popular Music . George O. Carney , ED. Development and Underdevelopment . John Cole . Mobility and Employment in Urban Southeast Asia: Example from Indonesia and the Philippines . Michael A. Costello , Thomas R. Leinbach , AND Richard Ulack . Soviet Asia: Economic Development and National Policy Choices . Leslie Dienes . The Third World City . David Drakakis -Smith . Scholars' Guide to Washington, DC for Cartography and Remote Sensing Imagery (maps, charts, aerial photographs, satellite images, cartographic literature and geographic information systems). Ralph E. Ehrenberg . Population and Development in the Third World . Allan AND Anne Findlay . The Early Mapping of Hawaii . Gary L. Fitzpatrick . Energetics of Physical Environment: Energetic Approaches to Physical Geography . K. J. Gregory , ED. Wildland Recreation: Ecology and Management . William E. Hammitt and David N. Cole . Agricultural Commercialization and Government Policy in Africa . J. Hinderink AND J. J. Sterkenburg . The Dynamics of American Housing . James W. Hughes AND George Sternlieb . Thailand: Buddhist Kingdom as Modern Nation State . Charles F. Keyes . Resolving Locational Conflict . Robert W. Lake , ED. Lands at Risk in the Third World: Local-level Perspectives . Peter D. Little and Michael M. Horowitz , EDS. Nathaniel Southgate Shaler and the Culture of American Science . David N. Livingstone . Regions: The Economics and Politics of Territory . Ann R. Markusen . Wetlands . William J. Mitsch and James G. Gosselink . Historical Geography: Progress and Prospect . Michael Pacione , ED. Loess and Periglacial Phenomena . Marton P$eacsi and Hugh M. French , EDS. Regional Management of Metropolitan Floodplains, Experience in the United States and Abroad . Rutherford H. Platt , ED. Human Cartography: Mapping the World of Man . Janos Szegö . Atlas of Great Lakes Indian History . Helen H. Tanner , ED. The Botany of Mangroves . P. B. Tomlinson . Urban Spatial Traffic Patterns . Rodney Vaughan . The Night After … Climatic and Biological Consequences of a Nuclear War . Yevgeni Velikhov , ED. Industrial Geography . H. D. Watts . Dictionary of Quotations in Geography . James O. Wheeler and Francis M. Sibley . Vermont Townscape . Norman Wiliams , Jr. , Edmund K. Kellogg and Peter M. Lavigne . 相似文献
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《The Professional geographer》2013,65(4):488-489
Book Reviewed in this article: Main Street: Northeastern Oregon: The Founding and Development of Small Towns. Barbara Ruth Bailey. Food Politics: The Regional Conflict. David N. Balaam and Michael J. Carey, eds. The International Economy and Industrial Development: Trade and Investment in the Third World. R. Ballance, J. Ansari and H. Singer. Neighborhoods in Urban America. Ronald H. Bayor, ed. The English Heartland. By Robert Beckinsale and Monica Beckinsale. Regional Dimensions of Industrial Policy. Michael E. Bell and Paul S. Lande, eds. Tension Areas of the World. D. Gordon Bennett, ed. Latin America: an Introductory Survey. B. W. Blouet and O. M. Blouet, eds. Integration and Division: Geographical Perspectives on the Northern Ireland Problem. Frederick W. Boal and J. Neville H. Douglas, eds. Energy and Land Use. Robert W. Burchell and David Listokin, eds. Slopes and Weathering. Michael Clarke and John Small. Alaska's Rural Development. Peter G. Cornwall and Gerald McBeath, eds. The Politics of Park Design: A History of Urban Parks in America. Galen Cranz. World Congress on Land Policy, 1980, Proceedings. Matthew Cullen and Sharon Woolery, eds. Oregon Divided: A Regional Geography. Samuel N. Dicken and Emily F. Dicken. Urban Food Marketing and Third World Rural Development. T. Scarlett Epstein. South Africa: Spatial Frameworks for Development. T. J. D. Fair. Institutions and Geographical Patterns. Robin Flowerdew, ed. Industrialization of U.S. Agriculture, An Interpretive Atlas. Howard F. Gregor. Planning Theory: Prospects for the 1980s. Patsy Healy, Glen McDougall and Michael J. Thomas, eds. Neighborhood Mobilization: Redevelopment and Response. Jeffrey R. Henig. The American Urban System: A Geographical Perspective. R. J. Johnston. Climate, History and the Modern World. Hubert H. Lamb. Climate and History: Studies in Past Climates and Their Impact on Man. T. M. L. Wigley, M. J. Ingram and G. Farmer. China: Railways and Agricultural Development, 1875–1935. Ernest P. Liang. A Desirable Energy Future—A National Perspective. Robert S. Livingston, T. D. Anderson, T. M. Besmann, M. Olszewski, A. M. Perry, and C. D. West. Topothesia: Essays Presented to T. S. Ó Máille. B. S. Mac Aodha, ed. Transportation for the Poor: Research in Rural Mobility. Hal S. Maggied. Land Uses in American Cities. Harold M. Mayer and Charles R. Haves. Industrial Organisation and Location. Philip McDermott and Michael Taylor. Human Adaptability: an Introduction to Ecological Anthropology. Emilio F. Moran. Regional Analysis and the New International Division of Labor. Frank Moulaert and Patricia W. Salinas, eds. The Nuclear War Atlas. Victoriaville, Quebec, Canada: Urbanization and Environmental Quality. Isao Orishimo. The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise. John Prest. Earthfire, The Eruption of Mount St. Helens. Charles Rosenfeld and Robert Cooke. Contest for the South China Sea. Marwyn S. Samuels. The Future of the Wetlands: Assessing Visual-Cultural Values. Richard C. Smardon, ed. Tucson: the Life and Times of An American City. C. L. Sonnichsen. The Geography of Multinationals. Michael Taylor and Nigel Thrift, eds. Impact of Marine Pollution on Society. Virginia Tippie and Dana Kester. Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham. Jerry A. Webman. Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942. Robert C. West, ed. Cartographic Drawing with Computers. P. Yoeli. 相似文献
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《The Professional geographer》1983,35(4):488-524
Book Reviewed in this article: Main Street: Northeastern Oregon: The Founding and Development of Small Towns . Barbara Ruth Bailey . Food Politics: The Regional Conflict . David N. Balaam and Michael J. Carey , eds. The International Economy and Industrial Development: Trade and Investment in the Third World . R. Ballance , J. Ansari and H. Singer . Neighborhoods in Urban America . Ronald H. Bayor , ed. The English Heartland . By Robert Beckinsale and Monica Beckinsale . Regional Dimensions of Industrial Policy . Michael E. Bell and Paul S. Lande , eds. Tension Areas of the World . D. Gordon Bennett , ed. Latin America: an Introductory Survey . B. W. Blouet and O. M. Blouet , eds. Integration and Division: Geographical Perspectives on the Northern Ireland Problem . Frederick W. Boal and J. Neville H. Douglas , eds. Energy and Land Use . Robert W. Burchell and David Listokin , eds. Slopes and Weathering . Michael Clarke and John Small . Alaska's Rural Development . Peter G. Cornwall and Gerald Mc Beath , eds. The Politics of Park Design: A History of Urban Parks in America . Galen Cranz . World Congress on Land Policy, 1980, Proceedings . Matthew Cullen and Sharon Woolery , eds. Oregon Divided: A Regional Geography . Samuel N. Dicken and Emily F. Dicken . Urban Food Marketing and Third World Rural Development . T. Scarlett Epstein . South Africa: Spatial Frameworks for Development . T. J. D. Fair . Institutions and Geographical Patterns . Robin Flowerdew , ed. Industrialization of U.S. Agriculture, An Interpretive Atlas . Howard F. Gregor . Planning Theory: Prospects for the 1980s . Patsy Healy , Glen Mc Dougall and Michael J. Thomas , eds. Neighborhood Mobilization: Redevelopment and Response . Jeffrey R. Henig . The American Urban System: A Geographical Perspective . R. J. Johnston . Climate, History and the Modern World . Hubert H. Lamb . Climate and History: Studies in Past Climates and Their Impact on Man . T. M. L. Wigley , M. J. Ingram and G. Farmer . China: Railways and Agricultural Development, 1875–1935 . Ernest P. Liang . A Desirable Energy Future—A National Perspective . Robert S. Livingston , T. D. Anderson , T. M. Besmann , M. Olszewski , A. M. Perry , and C. D. West . Topothesia: Essays Presented to T. S. Ó Máille . B. S. Mac Aodha , ed. Transportation for the Poor: Research in Rural Mobility . Hal S. Maggied . Land Uses in American Cities . Harold M. Mayer and Charles R. Haves . Industrial Organisation and Location . Philip Mc Dermott and Michael Taylor . Human Adaptability: an Introduction to Ecological Anthropology . Emilio F. Moran . Regional Analysis and the New International Division of Labor . Frank Moulaert and Patricia W. Salinas , eds. The Nuclear War Atlas. Victoriaville, Quebec, Canada : Urbanization and Environmental Quality . Isao Orishimo . The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise . John Prest . Earthfire, The Eruption of Mount St. Helens . Charles Rosenfeld and Robert Cooke . Contest for the South China Sea . Marwyn S. Samuels . The Future of the Wetlands: Assessing Visual-Cultural Values . Richard C. Smardon , ed. Tucson: the Life and Times of An American City. C. L. Sonnichsen . The Geography of Multinationals . Michael Taylor and Nigel Thrift , eds. Impact of Marine Pollution on Society . Virginia Tippie and Dana Kester . Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham . Jerry A. Webman . Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942 . Robert C. West , ed. Cartographic Drawing with Computers . P. Yoeli . 相似文献
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《寒旱区科学》2014,(4):I0001-I0001
Permafrost engineering has been developing rapidly in recent years. Many projects have been undertaken with the latest technologies and show their importance in supporting regional social and economical development. For example, the Qinghai-Tibet Railway has been a milestone project in permafrost engineering. However, when designing and building infrastructures in cold regions, 相似文献
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HAYASHI Hiroaki 《资源与生态学报(英文版)》2014,5(4):395-397
<正>1 Characteristics of Kunisaki GIAS and aims of this research Kunisaki GIAHS in the Kunisaki peninsula and Usa area,Oita,Japan,is a system where forestry,agricultural production,and fisheries are sustained by the strong connection between Sawtooth Oak forest,multiple interlinked irriga tion ponds,and Seto Inland Sea(Vafadari 2013a;2013b;Hayashi 2013).This area receive around 1,500 mm of annual precipitation with a 相似文献
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P. Guilizzoni A. Marchetto A. Lami N. G. Cameron P. G. Appleby N. L. Rose Ø. A. Schnell C. A. Belis A. Giorgis L. Guzzi 《Journal of Paleolimnology》1996,15(3):245-264
A palaeoecological study of an oligotrophic alpine lake, Paione Superiore (Italy), provided a record of historical changes in water quality. Historical trends in lake acidification were reconstructed by means of calibration and regression equations from diatoms, chrysophycean scales and pigment ratios. The historical pH was inferred by using two different diatom calibration data sets, one specific to the alpine region. These pH trends, together with the record of sedimentary carbonaceous particles and chironomid remains, indicate a recent acidification of this low alkalinity lake.Concentration of total organic matter, organic carbon, nitrogen, biogenic silica (BSiO2), chlorophyll derivatives (CD), fucoxanthin, diatom cell concentration and number of chironomid head capsules increased during the last 2–3 decades. When expressed as accumulation rates, most of these parameters tended to decrease from the past century to c. 1950, then all except P increased to the present day. A marked increase in sedimentary nitrogen may be related to atmospheric pollution and to the general increases in output of N in Europe. High C/N ratios indicate a prevailing allochthonous source of organic matter.Finally, the increase in measured air temperature from the mid-1800's appeared to be related to lake water pH before industrialization: cold periods generally led to lower pH and vice-versa. The more recent phenomenon of anthropogenic acidification has apparently decoupled this climatic-water chemistry relationship. 相似文献
19.
K. F. Walker I. G. Dunn D. Edwards T. Petr H. Z. Yang 《International Journal of Salt Lake Research》1995,4(3):169-222
Quinghai Hu is a large, high-altitude, saline lake in north-western China, and supports a fishery based on an endemic species of naked carp (snow trout). The fish take seven years to attain maturity and a marketable weight of 300 g, and have a lifespan of 14–21 years under the present fishery regime. They seasonally migrate from the lake to spawn over the gravel beds of inflowing rivers, but these areas have been reduced by weirs and irrigation diversions and recruitment may have declined. The population may have been affected also by a 1.85-m fall in the lake level over the past 30 years, and by associated changes in salinity. The fishery was opened to large-scale exploitation in 1958. Yields declined sharply (max. 28,523 tonnes, 1960) as the larger, older fish were removed, and then more slowly (min. 2523 tonnes, 1983). Since 1987 the fish factory has been limited to an annual quota of 1200 tonnes, taken by a fleet of four pair trawlers. Another 800 tonnes are taken by licensed fishermen, mainly using gill nets, and perhaps 1000 tonnes are taken illegally. The estimated total catch in 1992 was 3000 tonnes. New trawlers introduced in 1989–90 substantially increased the factory's catch per unit effort, and in 1990 the quota was virtually filled in one month in a zone within 20 km of the factory. Although this could suggest that the stocks will be conserved if the quota is retained, at least half of the catch in 1989–92 consisted of immature individuals. Trawling operations recently were suspended following a further decline in the catch after 1992. While the new trawlers are capable of a major increase in effort, neither the changing environment, the fish stocks or the present markets favour intensified pressure. Gillnets may provide better control over the minimum size limit and may cause less damage than trawling. Other options to improve the viability and profitability of the fishery include improvements in handling, processing and marketing. Failure to develop the fishery may encourage attempts to introduce exotic fish, at some risk to survival of the local species. 相似文献