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Remote Sensing of Selected Winter and Spring Host Plants of Tarnished Plant Bug (Heteroptera: Miridae) and Herbicide Use Strategies as a Management Tactic

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American j.urnal of Plant Sciences 2015年第8期6卷 1313-1327页

作者： Donald L. Sudbrink steven j. thomson Reginald S. Fletcher F. Aubrey Harris Patrick j. English j.mes T. Robbins Austin Peay State University Department of Agriculture Clarksville USA United States Department of Agriculture Agricultural Research Service Crop Production Systems Research Unit Stoneville USA Delta Research and Extension Center Mississippi State University Stoneville USA

Remote sensing was used in a series of experiments over a three-year period to obtain spectral reflectance data for studying differences in vegetation indices between grasses, broadleaf plants, and grass/broadleaf plant mixtures. Selected non-crop winter and spring host plants of tarnished plant bug, Lygus lineolaris, were planted in field-plot experiments. Multispectral reflectance data were aerially acquired with both a Real-Time Digital Airborne Camera System (RDACS) sensor and Geospatial Systems (Duncan Tech) MS-2100 multispectral camera. The following six vegetation indices of spectral reflectance were evaluated in this study: normalized difference vegetation index, ratio vegetation index, green normalized difference vegetation index, green vegetation index, green ratio vegetation index, and Ashburn vegetation index. Vegetation indices calculated with imagery data for the grasses and broadleaves differed significantly;there appeared to be more discriminating differences between vegetation indices for grasses and broadleaf plants when the indices were based on a combination of green and near infrared or green and red spectral bands than when the indices were based on red and near infrared spectral bands. Insect data from these studies confirm that tarnished plant bug prefers broadleaf host plants, but can use Italian ryegrass for food and reproduction. The narrow temporal window of host suitability for Italian ryegrass may limit its significance. Herbicide destruction of broadleaf host plants in early spring prevented the tarnished plant bug population increases that occurred in untreated plots. Findings of this study would be useful in site-specific vegetation management decisions in programs such as the prototypical area-wide tarnished plant bug management experiment conducted in the Delta region of Mississippi.

关键词： Remote Sensing Vegetation Index Lygus lineolaris Area-Wide Management

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亚洲高山流域千年尺度地表剥蚀的制约因素

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中国科学:地球科学 2025年第1期 75-94页

作者：杨业 steven A.BINNIE 徐胜刘丛强 Tibor j.DUNAI 天津大学地球系统科学学院表层地球系统科学研究院 Institute of Geology and Mineralogy University of Cologne

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率... 详细信息

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率变化范围从（7.4±0.7）mm ka-1（1σ;青藏高原内部）到（9,646744+777）mm ka-1（1σ;青藏高原南部）跨四个数量级,中位数为186mm ka-1.逐个像元计算的核素产率与传统模型使用质心坐标和平均高程计算的核素产率相比,后者96.6%核素产率被低估,其中高程差越大越被低估.两种方法计算的产率偏差可达40%,究其原因可能是流域高程分布不均和核素产率随海拔和纬度呈非线性变化.通过量化地表剥蚀速率与构造、气候、地形和岩性之间的相关性将有助于推演未知流域的剥蚀速率.从局部小尺度分析,亚热带台湾岛地区剥蚀速率可能主要受降水和新构造驱动的山体滑坡影响,而降水变化范围较窄的青藏高原东部的剥蚀速率主要受控于地形;冰川覆盖的高原地区剥蚀速率受冰川作用影响,如帕米尔、青藏高原内部和南部地区;青藏高原内部剥蚀速率较低是因为较低的降水和较高的侵蚀基准面,从而限制了河流的下切和地表起伏度演化.与局部小尺度强调单一主控因素不同,本研究对亚洲高山流域宏观大尺度进行量化分析发现:（1）地形指标（包括坡度、地形起伏度和河道陡峭指数）与剥蚀速率在千年尺度呈现一致的幂函数关系,而非简单线性;（2）剥蚀速率与气候（包括与海拔相关的降水、温度和植被覆盖度）和新构造活动（地震核密度分布）呈近似幂函数关系,为次要控制因素;（3）岩性与剥蚀速率没有明显的相关性,可能受限于流域复杂的岩性混合和低分辨率的可侵蚀指数数据.

关键词： 10Be剥蚀速率气候变化构造抬升地形梯度亚洲高山流域

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Portable device to assess dynamic accuracy of global positioning system(GPS)receivers used in agricultural aircraft

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International j.urnal of Agricultural and Biological Engineering 2014年第2期7卷 68-74页

作者： steven j.thomson Yanbo Huang Lowrey A.Smith United States Department of Agriculture(USDA) Agricultural Research Service(ARS)Crop Production Systems Research UnitStonevilleMS 38776USA

A device was designed to test the dynamic accuracy of Global Positioning System(GPS)receivers used in agricultural aircraft and other aerial *** system works by directing a sun-reflected light beam from the ground to the aircraft using mirrors.A photo detector points downward from the aircraft to detect the light beam,and photo detection circuitry triggers an event in the guidance system data file at the aircraft’s location corresponding to the precisely georeferenced position on the *** details are presented on the mirror-based light reflection system and photo-electronic circuitry designed to trigger an event in the guidance system’s log *** example application evaluated the horizontal accuracy of a stand-alone GPS receiver by matching dynamic data with data from the aircraft’s guidance *** indicated a 2.16 s lead in position registered by the stand-alone receiver over that registered by the aircraft’s guidance system GPS receiver,which had been previously evaluated to be within 0.13 s of Real-Time Kinematic(RTK)-referenced time and position.

关键词： GPS receiver accuracy agricultural aircraft aerial application remote sensing georeferencing UAV

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VARIABLE STEP-SIZE IMPLICIT-EXPLICIT LINEAR MULTISTEP METHODS FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONS

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j.urnal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven j. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have been developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementable variable step-size implicit-explicit （VSIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VSIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the Burgers＇ equation. These results demonstrate that by varying the time step-size, VSIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical behavior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variable step-size Zero-stability Burgers' equation.

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Mitogen-activated protein kinases mediate the oxidative burst and saponin synthesis induced by chitosan in cell cultures of Panax ginseng

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Science China(Life Sciences) 2004年第4期47卷 303-312页

作者： steven j. NEILL Centre for Research in Plant Science University of the West of England Bristol Coldharbour Lane Bristol BS16 1QY United Kingdom

Chitosan (CHN) specially induced the activities of 39 kD and 42 kD protein kinases in ginseng cells, which could be suppressed by an inhibitor of mitogen-activated protein kinase (MAPK) pathway, PD98059. The immunoprecipitation (IP) using MAPK antibody or kinase assay in vitro also showed that CHN-induced 42 kD and 39 kD protein kinases belonged to the MAPK family. PD98059 suppressed CHN-induced transcriptions of ginseng squalene synthase and ginseng squalene epoxidase genes (gss and gse), CHN-induced accumulation of β-Amyrin synthase (β-AS) and synthesis of saponin. These results showed that CHN-induced activities of MAPKs were necessary for the CHN-induced saponin synthesis. EGTA and LaCl3 suppressed CHN-induced 39 kD and 42 kD MAPK activities. Ruthenium red (RR) could suppress CHN-induced 39 kD activity. All of them suppressed CHN-induced saponin synthesis. These results indicated that CHN-induced increment of cytosolic calcium was necessary for CHN-induced saponin synthesis. PD98059 also suppressed CHN-induced oxidative burst (including the increment of activity of plasma membrane NADPH oxidase and production of H2O2), but diphenylene iodonium (DPI), dimethylthiourea (DMTU) and 2,5-dihydroxycinnamic acid methyl ester (DHC) could not suppress CHN-induced MAPK activities, which indicated that MAPK was possibly function upstream of CHN-induced oxidative burst. Keywords mitogen-activated protein kinase - chitosan - saponin

关键词： mitogen-activated protein kinase,chitosan,saponin.

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Characterization of spray deposition and drift from a low drift nozzle for aerial application at different application altitudes

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International j.urnal of Agricultural and Biological Engineering 2011年第4期4卷 28-33页

作者： Yanbo Huang steven j.thomson US Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStonevilleMS 38776USA

A complex interaction of controllable and uncontrollable factors is involved in aerial application of crop production and protection *** it is difficult to completely characterize spray deposition and drift,these important factors can be estimated with appropriate sampling protocol and *** height is an important variable influencing off-target spray drift,but this variable has not been easily measured or logged.A custom-configured aircraft-mounted laser with logging capabilities makes this *** study was designed to investigate droplet size and deposition characteristics of a low drift CP flat-fan nozzle at application altitudes 3.7 m,4.9 m,and 6.1 *** the study,CP flat-fan nozzles were set to a downward angle of 30 degrees applying a mixture of water,Syl-Tac®adj.vant,and Rubidium Chloride(RbCl)tracer at a 28.5 L/ha application *** droplets were collected using water sensitive paper(WSP)cards placed in the spray *** sheets were also placed in the swath and downwind for drift *** analysis indicated that median droplet diameter as determined by WSP in the spray swath was not significantly influenced by spray application ***,statistical analysis also indicated that concentration of RbCl tracer from Mylar samplers in the spray swath was not significantly influenced by application *** height had a significant effect on spray deposition from drift samplers,along with wind direction and relative *** results for drift samplers may have been influenced by shifts in wind direction that altered the relationship between orientation of samplers and wind.

关键词： deposition spray nozzle aerial application droplet spectra spray drift

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Estimation of cotton yield with varied irrigation and nitrogen treatments using aerial multispectral imagery

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International j.urnal of Agricultural and Biological Engineering 2013年第2期6卷 37-41页

作者： Yanbo Huang Ruixiu Sui steven j.thomson Daniel K.Fisher Crop Production Systems Research Unit Agricultural Research ServiceUnited States Department of AgricultureStonevilleMS 38776USA

Cotton yield varies spatially within a *** variability can be caused by various production inputs such as soil properties,water management,and fertilizer *** multispectral imaging is capable of providing data and information to study effects of the inputs on yield qualitatively and quantitatively in a timely and cost-effective fashion.A 10-ha cotton field with irrigation and non-irrigation 2×2 blocks was used in this *** nitrogen application treatments were randomized with two replications within each *** plant canopy was closed,airborne multispectral images of the field were acquired using a 3-CCD MS4100 *** images were processed to generate various vegetation *** vegetation indices were evaluated for the best performance to characterize *** effect of irrigation on vegetation indices was *** for yield estimation were developed and verified by comparing the estimated and actual *** indicated that ratio of vegetation index(RVI)had a close relationship with yield(R^(2)=0.47).Better yield estimation could be obtained using a model with RVI and soil electrical conductivity(EC)measurements of the field as explanatory variables(R^(2)=0.53).This research demonstrates the capability of aerial multispectral remote sensing in estimating cotton yield variation and considering soil properties and nitrogen.

关键词： remote sensing multispectral imagery cotton yield nitrogen irrigation soil properties

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Development and evaluation of low-altitude remote sensing systems for crop production management

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International j.urnal of Agricultural and Biological Engineering 2016年第4期9卷 1-11页

作者： Yanbo Huang steven j.thomson Howard j.Brand Krishna N.Reddy United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStoneville 38776USA United States Department of Agriculture National Institute of Food and AgricultureDivision of Agricultural SystemsWashington DC 20024USA Virginia Tech Department of Mechanical EngineeringBlacksburg 24061USA

Precision agriculture accounts for within-field variability for targeted treatment rather than uniform treatment of an entire *** is built on agricultural mechanization and state-of-the-art technologies of geographical information systems(GIS),global positioning systems(GPS)and remote sensing,and is used to monitor soil,crop growth,weed infestation,insects,diseases,and water status in farm fields to provide data and information to guide agricultural management *** agriculture began with mapping of crop fields at different scales to support agricultural planning and decision *** the development of variable-rate technology,precision agriculture focuses more on tactical actions in controlling variable-rate seeding,fertilizer and pesticide application,and irrigation in real-time or within the crop season instead of mapping a field in one crop season to make decisions for the next crop *** the development of aerial variable-rate systems,low-altitude airborne systems can provide high-resolution data for prescription variable-rate *** systems for multispectral imaging using a number of imaging sensors(cameras)were *** aerial vehicles(UAVs)provide a unique platform for remote sensing of crop fields at slow speeds and low-altitudes,and they are efficient and more flexible than manned agricultural airplanes,which often cannot provide images at both low altitude and low speed for capture of high-quality *** are also more universal in their applicability than agricultural aircraft since the latter are used only in specific *** study presents the low-altitude remote sensing systems developed for detection of crop stress caused by multiple ***,as a special platform,were discussed for crop sensing based on the researchers'studies.

关键词： low-altitude remote sensing agricultural airplane unmanned aerial vehicle(UAV) crop production management precision agriculture

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Ground-based hyperspectral remote sensing for weed management in crop production

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International j.urnal of Agricultural and Biological Engineering 2016年第2期9卷 98-109页

作者： Yanbo Huang Matthew A.Lee steven j.thomson Krishna N.Reddy United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitPO Box 350Stoneville MS 38776USA Department of Electrical and Computer Engineering Mississippi State UniversityMississippi State MS 39762USA United States Department of Agriculture National Institute of Food and AgricultureWashington DC 20024USA

Agricultural remote sensing has been developed and applied in monitoring soil,crop growth,weed infestation,insects,diseases and water status in farm fields to provide data and information to guide agricultural management *** agriculture has been implemented through prescription mapping of crop fields at different scales with the data remotely sensed from space-borne,airborne and ground-based ***-based remote sensing techniques offer portability,flexibility and controllability in applications for precision *** weed management,crop inj.ry from off-target herbicide spray drift and herbicide resistance in weeds are two important *** precision weed management,ground-based hyperspectral remote sensing techniques were developed for detection of crop inj.ry from dicamba and differentiation between glyphosate resistant and sensitive *** research presents the techniques for ground-based hyperspectral remote sensing for these two *** illustrate the advantages of ground-based hyperspectral remote sensing for precision weed management.

关键词： ground-based remote sensing hyperspectral crop inj.ry herbicide resistance precision agriculture

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Development and prospect of unmanned aerial vehicle technologies for agricultural production management

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International j.urnal of Agricultural and Biological Engineering 2013年第3期6卷 1-10页

作者： Yanbo Huang steven j.thomson W.Clint Hoffmann Yubin Lan Bradley K.Fritz United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStonevilleMS 38776USA United States Department of Agriculture Agricultural Research ServiceAreawide Pest Management Research UnitCollege StationTX 77845USA

Unmanned aerial vehicles have been developed and applied to support agricultural production *** with piloted aircraft,an Unmanned Aerial Vehicle(UAV)can focus on small crop fields at lower flight altitudes than regular aircraft to perform site-specific farm management with higher *** can also“fill in the gap”in locations where fixed winged or rotary winged aircraft are not readily *** agriculture,UAVs have primarily been developed and used for remote sensing and application of crop production and protection *** of fertilizers and chemicals is frequently needed at specific times and locations for site-specific *** monitoring of crop plant health is often required at very high resolution for accurate site-specific management as *** paper presents an overview of research involving the development of UAV technology for agricultural production ***,systems and methods are examined and *** limitations of current UAVs for agricultural production management are discussed,as well as future needs and suggestions for development and application of the UAV technologies in agricultural production management.

关键词： unmanned aerial vehicle aircraft aerial application technology sensor remote sensing precision agriculture agricultural aviation

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