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Soil Moisture and Oilseed Rape Yields as Affected by Configuration of Ridge-furrow Tillage in the Semiarid Region of china

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Soil Moisture and Oilseed Rape Yields as Affected by Configu...

Research on the damage of the Great Wall of Ming Dynasty in beijing by remote sensing

2007中国科协年会

作者： Liu Muxing~1 Wang Jingai~(2,4. Liu Lianyou~(2,3) Yan Ping~(2,3) 1.College of City and Environment,Huazhong normal university,Wuhan 4.0079,china 2.Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education,beijing normal university,beijing 100875,china 3.College of Resources Science & Technology,beijing normal university,beijing 100875,china 4.College of Geography and remote {14. Sciences,beijing normal university,beijing 100875,china

Ridge-furrow tillage is a kind of conservation tillage widely used for soil and water conservation in agriculture,with crop planted in ridge or *** previous researches mostly focus on the effects of ridge-furrow tillage with crop planted in ridges on crop growth and soil water content,Influence of ridge-forrow tillage with crop planted in furrows are not well documented,despite it is helpful to crop growth in arid and semiarid *** purpose of this study was evaluating the effect of ridge-furrow tillage with different surface configurations and crop planted in furrow,on the efficiency for rainwater harvesting and crop production,to determine the optimal surface configuration of ridge-furrow *** parameters of ridge heights (H) and ridge-furrow ratios (R,ratio between H and furrow width,W) were defined to determine the configuration of ridge-furrow *** field experiments,seasonal dynamic variation of volumetric soil water content, aboveground biomass and yields of oilseed rape (Brassica napus L.) were *** treatments included four kinds of ridge-furrow tillage with oilseed rape planted in furrow and one kind of conventional field tillage (CT) for *** results indicate that relative to CT,ridge-furrow tillage increased volumetric soil water content of the plow layer (0-30 cm) by 4.2%-12.1%,decreased its fluctuation in the growing season of oilseed *** the soil profile under ridge-furrow tillage,soil layer with the highest soil water content appeared in the depth of 0-30 cm,which helped oilseed rape absorb water by *** aboveground biomass,pods per plant and 1000-seed weigh under ridge-furrow tillage were larger than that under *** field comparison of oilseed rape yields under four forrow planting practices with 15,25 cm H and 1/6,1/12,1/24.R,we found the practice with 25 cm H and 1/24.R increased the efficiency of water harvesting,the growth and yield of the oilseed rape more ***,we recommend furr

关键词： ridge-furrow tillage furrow planting volumetric soil water content aboveground biomass theoretical yield rainfed agriculture

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Science china(Technological Sciences) 2008年第S1期51卷 195-202页

作者： LI XiaoJuan,GONG HuiLi,ZHANG Ou,ZHANG WeiGuang & SUN YongHua The Key Lab of 3D Information Acquisition and Application,MOE,the Key Lab of beijing Resource Envi-ronment and gis,and College of Resource Environment & Tourism,Capital normal university,beijing 100037,{4. The Key Lab of 3D Information Acquisition and Application MOE the Key Lab of Beijing Resource Environment and GIS and College of Resource Environment & Tourism Capital Normal University Beijing China

Using aerial photos and high resolution satellite images of the year of 2004.this paper establishes remote sensing interpretation marks of the Great Wall of Ming Dynasty's damaged levels. Based on field survey and remote sensing survey in 1984.we analyzed present situation and changing characteristics being of the Great Wall of Ming Dynasty in {4.. The results show that about 7.02% of the wall is well-preserved (about 25861 m); 31.5% of the wall is slightly or moderately dam-aged (about 115989 m); 61.5% of the wall is badly damaged (about 226379 m). This paper analyzes the dynamic change of the Great Wall of Ming Dynasty. It shows that the damaged situation of the Great Wall of Ming Dynasty in {4. is serious. From 1984.to 2004.the well-preserved wall is decreased by 33206 m (decreased by 56%); badly damaged wall increased by 51207 m (increased by 67%). Finally,this paper analyzes the influence factors of damaging Great Wall. The conclusion is as follows: The damaged Great Wall is generally near the roads and villages,small slope,and easily arriving land.

关键词： the Great Wall of Ming Dynasty remote sensing interpreting damage dynamic change spatial analysis

Eco-Environmental Vulnerability Evaluation in the Yellow River Basin,china

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Pedosphere 2008年第2期18卷 171-182页

作者： WANG Si-Yuan LIU Jing-Shi YANG Cun-Jian Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 （China） Institute of Electronics Chinese Academy of Sciences Beijing 100080 （China） Centre of RS and gis Applications Sichuan Normal University Chengdu 610066 （China）

Using remote sensing(RS)data and geographical information system(gis),eco-environmental vulnerability and its changes were analyzed for the Yellow River Basin,*** objective of this study was to improve our understanding of eco-environmental changes so that a strategy of sustainable land use could be *** environmental numerical model was developed using spatial principal component analysis(SPCA)*** model contains twelve factors that include variables of land use,soil erosion,topography,climate,and *** this model,synthetic eco- environmental vulnerability index(SEVI)was computed for 1990 and 2000 for the Yellow River *** SEVI was classified into six levels,potential,slight,light,medium,heavy,and very heavy,following the natural breaks classification. The eco-environmental vulnerability distribution and its changes over the ten years from 1990 to 2000 were analyzed and the driving factors of eco-environmental changes were *** results show that the eco-environmental vulnerability in the study area was at medium level,and the eco-environmental quality had been gradually improved on the ***,the eco-environmental quality had become worse over the ten years in some *** the study area,population growth,vegetation degradation,and governmental policies for eco-environmental protection were found to be the major factors that caused the eco-environmental changes over the ten years.

关键词： eco-environmental vulnerability geographic information system (gis) remote sensing (RS) spatial principal component analysis Yellow River Basin

remote sensing application system for water environments developed for Environment Satellite 1

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Science china Earth Sciences 2010年第S1期53卷 45-50页

作者： WU ChuanQing1,WANG Qiao1,ZHANG YongJun1,LI JunSheng2,WU YuanFeng2,ZHU Li1 & YAO YanJuan1 1 Satellite Environment center,Ministry of Environmental Protection,beijing 100029,china 2.center for Earth Observation and Digital Earth,Chinese Academy of Sciences,beijing 100190,china Satellite Environment center Ministry of Environmental Protection Beijing China center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing China

remote sensing data collected by the Environment Satellite I are characterized by high temporal resolution,high spectral resolution and mid-high spatial *** designed the remote sensing Application System for Water Environments(RSASWE) to create an integrated platform for remote sensing data processing,parameter information extraction and thematic mapping using both remote sensing and gis *** system provides support for regional water environmental monitoring,and prediction and warning of water *** to process and apply data collected by Environment Satellite I,this system has automated procedures including clipping,observation geometry computation,radiometric calibration,6S atmospheric correction and water quality parameter *** consists of six subsystems:remote sensing image processing,basic parameter inversion,water environment remote sensing thematic outputs,application outputs,automated water environment outputs and a non-point source pollution monitoring *** present RSASWE plays an important role in operations at the Satellite Environment center.

关键词： water environment remote sensing Application System Environment Satellite 1

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东北漫岗黑土区春季冻融期浅沟侵蚀

山地学报 2006年第3期24卷 306-311页

作者：张永光伍永秋刘宝元北京师范大学沙漠与沙区资源研究所北京师范大学环境演变与自然灾害教育部重点实验室北京100875 北京师范大学地理与遥感科学学院北京100875

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2005年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14.、16条,浅沟总长度分别达3 269 m、2 14. m,浅沟密度... 详细信息

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2005年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14.、16条,浅沟总长度分别达3 269 m、2 14. m,浅沟密度分别为908 m/km2、766 m/km2,侵蚀深度分别为0.17 mm、0.16 mm,侵蚀模数分别达181.8 t/km2、173.6 t/km2。2005年春季两流域浅沟侵蚀期的径流深分别是6.8 mm、7.7 mm。分析表明,研究区在春季表层土壤解冻、地表裸露和存在季节性冻土层的条件下,春季融雪及强降水易造成强烈的浅沟侵蚀。在分布上,浅沟一般位于坡面的中下部,而且多发育在瓦背状坡面的集流水路上。另外,耕作措施对浅沟的形成和发展也有重要影响。

关键词：黑土区强降水冻融浅沟侵蚀

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基于分形特征的网络异常检测方法研究

计算机工程与应用 2004年第22期40卷 34-36页

作者：刘峰胡昌振帅艳民北京理工大学机电工程学院北京100081 北京师范大学地理与遥感科学学院北京100875

网络连接同许多其它现象一样,呈现出一种统计自相似性。论文根据此特征提出了一种基于分形特征的网络异常检测方法,该方法能够根据网络连接分形维数的变化,有效地检测网络拒绝服务攻击和端口扫描等异常情况,并通过模拟实验证明了该方法... 详细信息

网络连接同许多其它现象一样,呈现出一种统计自相似性。论文根据此特征提出了一种基于分形特征的网络异常检测方法,该方法能够根据网络连接分形维数的变化,有效地检测网络拒绝服务攻击和端口扫描等异常情况,并通过模拟实验证明了该方法的可行性。

关键词：网络安全分形自相似

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土壤的多角度偏振反射光谱研究

土壤学报 2004年第3期41卷 476-479页

作者：赵虎晏磊赵云升北京大学遥感与地理信息系统研究所北京100871 东北师范大学地理系长春130024

在利用多波段、多时相、高光谱的遥感数据来提高遥感对地物的识别能力的同时~[1]，人们注意到角度信息在遥感图像识别和分类中起到的影响和贡献~[2]，即地物在2π空间上的三维光谱特征。在早期的遥感，主要采取垂直收集对地观测数据。... 详细信息

在利用多波段、多时相、高光谱的遥感数据来提高遥感对地物的识别能力的同时~[1]，人们注意到角度信息在遥感图像识别和分类中起到的影响和贡献~[2]，即地物在2π空间上的三维光谱特征。在早期的遥感，主要采取垂直收集对地观测数据。根据不同的地物具有不同的吸收、反射和发射电磁波的能力，来分辨地球表层的地物分布。这里基于一个假定：假定目标地物的反射光谱在2π空间内分布是一致的(朗伯体)。随着遥感的深入，这种假定引发的结论与实际相差较大。而且在单一角度下常出现不同地物对应相同的光谱反射率，上述方法存在误判。如果从多个角度来观测地物，不同地物在多角度下具有相同光谱反射率的几率会大大缩小。其次不同地物的物质成分、颜色、结构、构造的不同，其光谱的偏振态以及在2π空间的三维光谱特征都存在差异。通过这些差异，对于精确识别地物，提高遥感的实际应用具有重要意义。

关键词：土壤多角度偏振反射光谱遥感图像识别图像分类地物

Spectral response of rice(Oryza sativa L.) leaves to Fe^(2+) stress

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Science china(Life Sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2,CHEN Xin1,SHI Yi1 & LIU XinHui3 1 Key Laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,china 2 Graduate School of Chinese Academy of Sciences,beijing 10004.,china 3 State Key Joint Laboratory of Environmental Simulation and Pollution Control,School of Environment,beijing {4. university,beijing 100875,china Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Graduate School of Chinese Academy of Sciences Beijing China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A laboratory water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2+ *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 4.0―670 nm under Fe2+ stress),A2(integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2+ stress) and S(blue-shift range of red edge curve under Fe2+ stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2+ *** the increase of Fe2+ in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2 and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2+ lake eutrophication

The application of very high resolution satellite image in urban vegetation cover investigation:a case study of Xiamen City

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Journal of Geographical Sciences 2003年第3期13卷 265-270页

作者： CHENG Chengqi,Li Bin,MA Ting(Institute of remote sensing & gis, Peking university, {4. 100871, {4.) Institute of remote sensing & gis Peking University Beijing China

With the technological improvements of satellite sensors, we will acquire more information about the earth so that we have reached a new application epoch of observation on earth environmental change and cartography. But with the enhancement of spatial resolution, some questions have arisen in the application of using traditional image processing and classification methods. Aiming for such questions, we studied the application of IKONOS very high resolution image (1 m) in Xiamen City on Urban Vegetation Cover Investigation and discussed the difference between the very high resolution image and traditional low spatial resolution image at classification, information abstraction etc. It is an advantageous test for the large-scale application of very high resolution data in the future.

关键词： high resolution remote sensing vegetation cover investigation