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辽宁省玉米地水分盈亏时空分布特征及灌溉模式分区研究 被引量:28
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作者 魏新光 王铁良 +5 位作者 李波 刘守阳 姚名泽 解影 郑思宇 景竹然 《农业工程学报》 EI CAS CSCD 北大核心 2018年第23期119-126,共8页
根据不同区域农作物需水规律和水资源供需状况,对区域内干旱区域类型、水分盈亏特性与干旱发生频率等进行综合分析和科学区划,对于提高整个地区(流域)农作物水分利用效率和水资源高效利用具有重要意义。该文基于辽宁省27个气象站1955—2... 根据不同区域农作物需水规律和水资源供需状况,对区域内干旱区域类型、水分盈亏特性与干旱发生频率等进行综合分析和科学区划,对于提高整个地区(流域)农作物水分利用效率和水资源高效利用具有重要意义。该文基于辽宁省27个气象站1955—2014年逐日气象数据和玉米生长发育资料,对辽宁省不同玉米种植区域玉米生育期的需水过程、需水量、灌溉需水量、水分盈亏指数(crop water surplus deficit index,CWSDI)、干旱发生频率等的时空分布特征进行深入研究,得到以下结论:辽宁省不同区域玉米逐月需水量均呈现单峰变化趋势,7月需水量最大,全省生育期总需水量在335~391 mm之间;不同水文年玉米需水亏缺量在0~220 mm之间;CWSDI和干旱发生频率在全省的空间分布规律类似,综合两指标的数值分布特征,将辽宁省玉米灌区划分为干旱区和易旱区2种类型,并结合不同水文年型玉米灌溉制度,将辽宁省玉米种植区划分为7种灌溉模式。该研究成果可以为辽宁省区域农业用水区划与管理提供理论依据。 展开更多
关键词 需水量 灌溉 干旱 作物水分盈亏指数 玉米
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基于数字化植物表型平台(D3P)的田间小麦冠层光截获算法开发 被引量:8
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作者 刘守阳 金时超 +2 位作者 郭庆华 朱艳 Fred Baret 《智慧农业(中英文)》 2020年第1期87-98,共12页
冠层光截获能力是反映作物品种间差异的重要功能性状,高通量表型冠层光截获对提高作物改良效率具有重要意义。本研究以小麦为研究目标,利用数字化植物表型平台(D3P)模拟生成了100种冠层结构不同的小麦品种在5个生育期的三维冠层场景,记... 冠层光截获能力是反映作物品种间差异的重要功能性状,高通量表型冠层光截获对提高作物改良效率具有重要意义。本研究以小麦为研究目标,利用数字化植物表型平台(D3P)模拟生成了100种冠层结构不同的小麦品种在5个生育期的三维冠层场景,记录了从原始冠层结构中提取的绿色叶面积指数(GAI)、平均倾角(AIA)和散射光截获率(FIPAR_(dif))信息作为真实值,进一步利用上述三维小麦场景开展了虚拟的激光雷达(LiDAR)模拟实验,生成了对应的三维点云数据。基于模拟的点云数据提取了其高度分位数特征(H)和绿色分数特征(GF)。最后,利用人工神经网络(ANN)算法分别构建了从不同LiDAR点云特征(H、GF和H+GF)输入到FIPAR_(dif)、GAI和AIA的反演模型。结果表明,对于GAI、AIA和FIPAR_(dif),预测精度从高到低对应的点云特征输入为GF+H> H> GF。由此可见,H特征对提高目标表型特性的估算精度起到了重要作用。输入GF+H特征,在中等测量噪音(10%)情况下,FIPAR_(dif)和GAI的估算均获得了满意精度,R^2分别为0.95和0.98,而AIA的估算精度(R^2=0.20)还有待进一步提升。本研究基于D3P模拟数据开展,算法的实际表现还有待通过田间数据进一步验证。尽管如此,本研究验证了D3P协助表型算法开发的能力,展示了高通量LiDAR数据在估算田间冠层光截获和冠层结构方面的较高潜力。 展开更多
关键词 冠层光截获 高通量表型 LIDAR 数字化植物表型平台(D3P) 小麦冠层
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Transient response of a concrete tunnel in an elastic rock with imperfect contact 被引量:4
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作者 R.Shakeri A.Mesgouez G.Lefeuve-Mesgouez 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第5期605-612,共8页
The two-dimensional transient response of an imperfect bonded circular lined pipeline lying in an elastic infinite medium is investigated.Imperfect boundary conditions between the surrounding elastic rock and the tunn... The two-dimensional transient response of an imperfect bonded circular lined pipeline lying in an elastic infinite medium is investigated.Imperfect boundary conditions between the surrounding elastic rock and the tunnel are modelled with a two-linear-spring design.The novelty of the manuscript consists in studying at the same time transient regimes and imperfect bonded interfaces for simulating the dynamic response of a tunnel embedded in an elastic infinite rock.Wave propagation fields in tunnel and rock are expressed in terms of infinite Bessel and Hankel series.To solve the transient problem,the Laplace transform and the associated Durbin’s algorithm are performed.To exhibit the dynamic responses,influences of various parameters such as the quality of the interface conditions and the thickness of the lining are presented.The dynamic hoop stresses and the solid displacements of both the tunnel and the rock are also proposed. 展开更多
关键词 Dynamic response Imperfect interface Circular tunnel Semi-analytical approach Transient wave propagation
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Using irrigation intervals to optimize water-use efficiency and maize yield in Xinjiang,northwest China 被引量:8
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作者 Guoqiang Zhang Dongping Shen +10 位作者 Bo Ming Ruizhi Xie Xiuliang Jin Chaowei Liu Peng Hou Jun Xue Jianglu Chen Wanxu Zhang Wanmao Liu Keru Wang Shaokun Li 《The Crop Journal》 SCIE CAS CSCD 2019年第3期322-334,共13页
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel... Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation. 展开更多
关键词 Irrigation frequency Soil moisture MAIZE High yield(>15 Mg ha^(-1)) Water use efficiency
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Global sensitivity analysis of wheat grain yield and quality and the related process variables from the DSSAT-CERES model based on the extended Fourier Amplitude Sensitivity Test method 被引量:11
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作者 LI Zhen-hai JIN Xiu-liang +2 位作者 LIU Hai-long XU Xin-gang WANG Ji-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第7期1547-1561,共15页
A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A maj... A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A major challenge of model application is the optimization and calibration of a considerable number of parameters.Sensitivity analysis(SA) has become an effective method to identify the importance of various parameters.In this study,the extended Fourier Amplitude Sensitivity Test(EFAST) approach was used to evaluate the sensitivity of the DSSAT-CERES model output responses of interest to 39 crop genotype parameters and six soil parameters.The outputs for the SA included grain yield and quality(take grain protein content(GPC) as an indicator) at maturity stage,as well as leaf area index,aboveground biomass,and aboveground nitrogen accumulation at the critical process variables.The key results showed that:(1) the influence of parameter bounds on the sensitivity results was slight and less than the impacts from the significance of the parameters themselves;(2) the sensitivity parameters of grain yield and GPC were different,and the sensitivity of the interactions between parameters to GPC was greater than those between the parameters to grain yield;and(3) the sensitivity analyses of some process variables,including leaf area index,aboveground biomass,and aboveground nitrogen accumulation,should be performed differently.Finally,some parameters,which improve the model’s structure and the accuracy of the process simulation,should not be ignored when maturity output as an objective variable is studied. 展开更多
关键词 global sensitivity analysis DSSAT EFAST wheat yield GRAIN protein content
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New Computerized Method for the Geochemical Classification of Precambrian Carbonate Rocks: Case of a Set of African Cap Carbonates 被引量:1
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作者 Hélène Miche Roland Simler +3 位作者 Pascal Affaton Olivia Mickala Florent Boudzoumou Michel Mbina 《International Journal of Geosciences》 2013年第10期37-49,共13页
Post-sedimentary transformations have masked or completely obliterated the structures and textures of Precambrian carbonate rocks. Therefore, methods of classification of the carbonate rocks founded on the observation... Post-sedimentary transformations have masked or completely obliterated the structures and textures of Precambrian carbonate rocks. Therefore, methods of classification of the carbonate rocks founded on the observation of primary structures or textural characteristics are ill-adapted. Consequently, only certain geochemical classification methods allow us to distinguish the various rock-types in the case of Neoproterozoic carbonates. After presenting the most suitable geochemical classifications, we propose a new classification into 14 groups based on a regular ternary diagram with computerized data input. For each sample of carbonate rock, analysis of calcium and magnesium contents allows us to calculate the input data for our diagram i.e. the percentages of Calcite, Dolomite and Insoluble Residue. To automate the application of this diagram, input parameters are created in a descriptive file “Roches.ternaires.txt” using an option called “Ternaires” in the “Diagrammes” software developed by Roland Simler. Thirty cap carbonates of Africa are used to validate this new method. 展开更多
关键词 CARBONATE Rock Cap CARBONATE Ternary DIAGRAM Software CALCITE DOLOMITE
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Global sensitivity analysis for choosing the main soil parameters of a crop model to be determined
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作者 Hubert Varella Samuel Buis +1 位作者 Marie Launay Martine Guérif 《Agricultural Sciences》 2012年第7期949-961,共13页
The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of inter... The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of interest and costly techniques may be used to measure them. It is therefore important to know which soil parameters need to be determined. It can be stated that those which affect significantly the output variable deserve an accurate determination while those which slightly affect the model output variable do not. This paper demonstrates how a global sensitivity analysis method based on variance decomposition can be applied on soil parameters in order to divide them in the two categories. The Extended FAST method applied to the crop model STICS and a set of 13 soil parameters first allows to calculate the part of variance explained by each soil parameter (giving global sensitivity indices of the soil parameters) and the coefficient of variation of the output variables (measuring the effect of the parameter uncertainty on each variable). These metrics are therefore used for deciding on the importance of the parameter value measurement. Different output variables (Leaf Area Index and chlorophyll content) are evaluated at different stages of interest while others (crop yield, grain protein content, soil mineral nitrogen) are evaluated at harvest. The analysis is applied on two different annual crops (wheat and sugar beet), two contrasted weather and two types of soil depth. When the uncertainty of the output generated by the soil parameters is large (coefficient of variation > 1/3), only the parameters having a significant global sensitivity indices (higher than 10%) are retained. The results show that the number of soil parameters which deserve an accurate determination can be significantly reduced by the use of this relevant method for appropriate management decision support. 展开更多
关键词 Global Sensitivity ANALYSIS Uncertainty ANALYSIS SOIL Parameters CROP Model STICS Management DECISION Support Agro-Environmental VARIABLES
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Hydrogeological Configuration of Grande Comore Island:Use of 3D Geological Modelling and Piezometry
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作者 Ibrahim Lhad Sosote Moctar Diaw +5 位作者 Ibrahima Mall Konstantinos Chalikakis Adriano Mayer Remi Valois Fatou Diop Ngom Abdillahi Mze Ali 《Open Journal of Modern Hydrology》 2025年第2期176-203,共28页
Hydrogeological modeling is an interesting and widely-used approach to improving our understanding of groundwater,both to test existing hypotheses on the behavior of hydrosystems and to predict their responses to vari... Hydrogeological modeling is an interesting and widely-used approach to improving our understanding of groundwater,both to test existing hypotheses on the behavior of hydrosystems and to predict their responses to various natural or man-made problems.Today,software such as Leapfrog Geo offers the possibility of building a 3D geological model with a more accurate representation of the subsurface.Statistical tools such as ordinary kriging can be used to simulate the spatial distribution of groundwater.These modeling approaches were combined to improve knowledge of the groundwater flow context within three massifs on the island of Grande Comore.The delineation of the 3D geometry of litho-stratigraphic units has enabled a more detailed conceptualization of groundwater flows in a complex volcanic environment.Piezometric interpolations were used to validate aquifer geometry.It has been demonstrated that an implicit geological model coupled with piezometry can provide very interesting information on the hydrogeological configuration of a volcanic massif.In the Karthala and Badjini massifs,the respective confined and semi-confined configurations of the aquifers are observed,with thicknesses that progressively decrease with distance from the coast.In the Grille massif,on the other hand,the aquifer configuration is unconfined,with thickness increasing with distance from the coast.In all three massifs,the flow of water in the underground hydrosystems is from the central part towards the coast,naturally following the geological configuration of the ground.It should be noted that the absence of data in the central parts of the massifs still leaves uncertainties about the geometry in these parts of the aquifers.However,the models that have been established provide valid hypotheses for characterizing the hydrogeological configuration at the scale of each massif. 展开更多
关键词 Aquifer Configuration Piezometry 3D Geological Modelling Flow Grille Massif Karthala Massif Badjini Massif Grande Comore Island
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The Global Wheat Full Semantic Organ Segmentation(GWFSS)dataset
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作者 Zijian Wang Radek Zenkl +33 位作者 Latifa Greche Benoit De Solan Lucas Bernigaud Samatan Safaa Ouahid Andrea Visioni Carlos A.Robles-Zazueta Francisco Pinto Ivan Perez-Olivera Matthew P.Reynolds Chen Zhu Shouyang Liu Marie-Pia D'argaignon Raul Lopez-Lozano Marie Weiss Afef Marzougui Lukas Roth Sébastien Dandrifosse Alexis Carlier Benjamin Dumont Benoît Mercatoris Javier Fernandez Scott Chapman Keyhan Najafian Ian Stavness Haozhou Wang Wei Guo Nicolas Virlet Malcolm J.Hawkesford Zhi Chen Etienne David Joss Gillet Kamran Irfan Alexis Comar Andreas Hund 《Plant Phenomics》 2025年第3期380-395,共16页
Computer vision is increasingly used in farmers'fields and agricultural experiments to quantify important traits.Imaging setups with a sub-millimeter ground sampling distance enable the detection and tracking of p... Computer vision is increasingly used in farmers'fields and agricultural experiments to quantify important traits.Imaging setups with a sub-millimeter ground sampling distance enable the detection and tracking of plant features,including size,shape,and colour.Although today's AI-driven foundation models segment almost any object in an image,they still fail for complex plant canopies.To improve model performance,the global wheat dataset consortium assembled a diverse set of images from experiments around the globe.After the head detection dataset(GWHD),the new dataset targets a full semantic segmentation(GWFSS)of organs(leaves,stems and spikes)covering all developmental stages.Images were collected by 11 institutions using a wide range of imaging setups.Two datasets are provided:ⅰ)a set of 1096 diverse images in which all organs were labelled at the pixel level,and(ⅱ)a dataset of 52,078 images without annotations available for additional training.The labelled set was used to train segmentation models based on DeepLabV3Plus and Segformer.Our Segformer model performed slightly better than DeepLabV3Plus with a mIOU for leaves and spikes of ca.90%.However,the precision for stems with 54%was rather lower.The major advantages over published models are:ⅰ)the exclusion of weeds from the wheat canopy,ⅱ)the detection of all wheat features including necrotic and se-nescent tissues and its separation from crop residues.This facilitates further development in classifying healthy vs.unhealthy tissue to address the increasing need for accurate quantification of senescence and diseases in wheat canopies. 展开更多
关键词 Wheat organ segmentation Field phenomics High-throughput phenotyping Breeding
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High-Throughput Measurements of Stem Characteristics to Estimate Ear Density and Above-Ground Biomass 被引量:10
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作者 Xiuliang Jin Simon Madec +3 位作者 Dan Dutartre Benoit de Solan Alexis Comar Frédéric Baret 《Plant Phenomics》 2019年第1期80-89,共10页
Total above-ground biomass at harvest and ear density are two important traits that characterize wheat genotypes.Two experiments were carried out in two different sites where several genotypes were grown under contras... Total above-ground biomass at harvest and ear density are two important traits that characterize wheat genotypes.Two experiments were carried out in two different sites where several genotypes were grown under contrasted irrigation and nitrogen treatments.A high spatial resolution RGB camera was used to capture the residual stems standing straight after the cutting by the combine machine during harvest.It provided a ground spatial resolution better than 0.2 mm.A Faster Regional Convolutional Neural Network(Faster-RCNN)deep-learning model was first trained to identify the stems cross section.Results showed that the identification provided precision and recall close to 95%.Further,the balance between precision and recall allowed getting accurate estimates of the stem density with a relative RMSE close to 7%and robustness across the two experimental sites.The estimated stem density was also compared with the ear density measured in the field with traditional methods.A very high correlation was found with almost no bias,indicating that the stem density could be a good proxy of the ear density.The heritability/repeatability evaluated over 16 genotypes in one of the two experiments was slightly higher(80%)than that of the ear density(78%).The diameter of each stem was computed from the profile of gray values in the extracts of the stem cross section.Results show that the stem diameters follow a gamma distribution over eachmicroplot with an average diameter close to 2.0mm.Finally,the biovolume computed as the product of the average stem diameter,the stem density,and plant height is closely related to the above-ground biomass at harvest with a relative RMSE of 6%.Possible limitations of the findings and future applications are finally discussed. 展开更多
关键词 BIOMASS STRAIGHT finally
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Scoring Cercospora Leaf Spot on Sugar Beet:Comparison of UGV and UAV Phenotyping Systems 被引量:4
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作者 S.Jay A.Comar +9 位作者 R.Benicio J.Beauvois D.Dutartre G.Daubige W.Li J.Labrosse S.Thomas N.Henry M.Weiss F.Baret 《Plant Phenomics》 2020年第1期225-242,共18页
Selection of sugar beet(Beta vulgaris L.)cultivars that are resistant to Cercospora Leaf Spot(CLS)disease is critical to increase yield.Such selection requires an automatic,fast,and objective method to assess CLS seve... Selection of sugar beet(Beta vulgaris L.)cultivars that are resistant to Cercospora Leaf Spot(CLS)disease is critical to increase yield.Such selection requires an automatic,fast,and objective method to assess CLS severity on thousands of cultivars in the field.For this purpose,we compare the use of submillimeter scale RGB imagery acquired from an Unmanned Ground Vehicle(UGV)under active illumination and centimeter scale multispectral imagery acquired from an Unmanned Aerial Vehicle(UAV)under passive illumination.Several variables are extracted from the images(spot density and spot size for UGV,green fraction for UGV and UAV)and related to visual scores assessed by an expert.Results show that spot density and green fraction are critical variables to assess low and high CLS severities,respectively,which emphasizes the importance of having submillimeter images to early detect CLS in field conditions.Genotype sensitivity to CLS can then be accurately retrieved based on time integrals of UGV-and UAV-derived scores.While UGV shows the best estimation performance,UAV can show accurate estimates of cultivar sensitivity if the data are properly acquired.Advantages and limitations of UGV,UAV,and visual scoring methods are finally discussed in the perspective of high-throughput phenotyping. 展开更多
关键词 ILLUMINATION MILLIMETER critical
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Estimates of Maize Plant Density from UAV RGB Images Using Faster-RCNN Detection Model:Impact of the Spatial Resolution 被引量:13
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作者 K.Velumani R.Lopez-Lozano +4 位作者 S.Madec W.Guo J.Gillet A.Comar F.Baret 《Plant Phenomics》 SCIE 2021年第1期181-196,共16页
Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices.The use of RGB images taken from UAVs may replace the traditional vi... Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices.The use of RGB images taken from UAVs may replace the traditional visual counting in fields with improved throughput,accuracy,and access to plant localization.However,high-resolution images are required to detect the small plants present at the early stages.This study explores the impact of image ground sampling distance(GSD)on the performances of maize plant detection at three-to-five leaves stage using Faster-RCNN object detection algorithm.Data collected at high resolution(GSD≈0:3 cm)over six contrasted sites were used for model training.Two additional sites with images acquired both at high and low(GSD≈0:6 cm)resolutions were used to evaluate the model performances.Results show that Faster-RCNN achieved very good plant detection and counting(rRMSE=0:08)performances when native high-resolution images are used both for training and validation.Similarly,good performances were observed(rRMSE=0:11)when the model is trained over synthetic low-resolution images obtained by downsampling the native training high-resolution images and applied to the synthetic low-resolution validation images.Conversely,poor performances are obtained when the model is trained on a given spatial resolution and applied to another spatial resolution.Training on a mix of high-and low-resolution images allows to get very good performances on the native high-resolution(rRMSE=0:06)and synthetic low-resolution(rRMSE=0:10)images.However,very low performances are still observed over the native low-resolution images(rRMSE=0:48),mainly due to the poor quality of the native low-resolution images.Finally,an advanced super resolution method based on GAN(generative adversarial network)that introduces additional textural information derived from the native high-resolution images was applied to the native low-resolution validation images.Results show some significant improvement(rRMSE=0:22)compared to bicubic upsampling approach,while still far below the performances achieved over the native high-resolution images. 展开更多
关键词 RCNN FASTER IMAGE
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A Double Swath Configuration for Improving Throughput and Accuracy of Trait Estimate from UAV Images 被引量:1
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作者 Wenjuan Li Alexis Comar +5 位作者 Marie Weiss Sylvain Jay Gallian Colombeau Raul Lopez-Lozano Simon Madec Frédéric Baret 《Plant Phenomics》 SCIE 2021年第1期378-388,共11页
Multispectral observations from unmanned aerial vehicles(UAVs)are currently used for precision agriculture and crop phenotyping applications to monitor a series of traits allowing the characterization of the vegetatio... Multispectral observations from unmanned aerial vehicles(UAVs)are currently used for precision agriculture and crop phenotyping applications to monitor a series of traits allowing the characterization of the vegetation status.However,the limited autonomy of UAVs makes the completion of flights difficult when sampling large areas.Increasing the throughput of data acquisition while not degrading the ground sample distance(GSD)is,therefore,a critical issue to be solved.We propose here a new image acquisition configuration based on the combination of two focal length(f)optics:an optics with f=4:2 mm is added to the standard f=8 mm(SS:single swath)of the multispectral camera(DS:double swath,double of the standard one).Two flights were completed consecutively in 2018 over a maize field using the AIRPHEN multispectral camera at 52 m altitude.The DS flight plan was designed to get 80%overlap with the 4.2 mm optics,while the SS one was designed to get 80%overlap with the 8 mm optics.As a result,the time required to cover the same area is halved for the DS as compared to the SS.The georeferencing accuracy was improved for the DS configuration,particularly for the Z dimension due to the larger view angles available with the small focal length optics.Application to plant height estimates demonstrates that the DS configuration provides similar results as the SS one.However,for both the DS and SS configurations,degrading the quality level used to generate the 3D point cloud significantly decreases the plant height estimates. 展开更多
关键词 optics OVERLAP ALTITUDE
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Analyzing Changes in Maize Leaves Orientation due to GxExM Using an Automatic Method from RGB Images 被引量:1
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作者 Mario Serouart Raul Lopez-Lozano +4 位作者 Gaëtan Daubige Maëva Baumont Brigitte Escale Benoit De Solan Frédéric Baret 《Plant Phenomics》 SCIE EI CSCD 2023年第2期239-252,共14页
The sowing pattern has an important impact on light interception efficiency in maize by determining the spatial distribution of leaves within the canopy.Leaves orientation is an important architectural trait determini... The sowing pattern has an important impact on light interception efficiency in maize by determining the spatial distribution of leaves within the canopy.Leaves orientation is an important architectural trait determining maize canopies light interception.Previous studies have indicated how maize genotypes may adapt leaves orientation to avoid mutual shading with neighboring plants as a plastic response to intraspecific competition.The goal of the present study is 2-fold:firstly,to propose and validate an automatic algorithm(Automatic Leaf Azimuth Estimation from Midrib detection[ALAEM])based on leaves midrib detection in vertical red green blue(RGB)images to describe leaves orientation at the canopy level;and secondly,to describe genotypic and environmental differences in leaves orientation in a panel of 5 maize hybrids sowing at 2 densities(6 and 12 plants.m^(−2))and 2 row spacing(0.4 and 0.8 m)over 2 different sites in southern France.The ALAEM algorithm was validated against in situ annotations of leaves orientation,showing a satisfactory agreement(root mean square[RMSE]error=0.1,R^(2)=0.35)in the proportion of leaves oriented perpendicular to rows direction across sowing patterns,genotypes,and sites.The results from ALAEM permitted to identify significant differences in leaves orientation associated to leaves intraspecific competition.In both experiments,a progressive increase in the proportion of leaves oriented perpendicular to the row is observed when the rectangularity of the sowing pattern increases from 1(6 plants.m^(−2),0.4 m row spacing)towards 8(12 plants.m^(−2),0.8 m row spacing).Significant differences among the 5 cultivars were found,with 2 hybrids exhibiting,systematically,a more plastic behavior with a significantly higher proportion of leaves oriented perpendicularly to avoid overlapping with neighbor plants at high rectangularity.Differences in leaves orientation were also found between experiments in a squared sowing pattern(6 plants.m^(−2),0.4 m row spacing),indicating a possible contribution of illumination conditions inducing a preferential orientation toward east-west direction when intraspecific competition is low. 展开更多
关键词 CULTIVAR SPACING PATTERN
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Self-Supervised Plant Phenotyping by Combining Domain Adaptation with 3D Plant Model Simulations: Application to Wheat Leaf Counting at Seedling Stage 被引量:5
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作者 Yinglun Li Xiaohai Zhan +8 位作者 Shouyang Liu Hao Lu Ruibo Jiang Wei Guo Scott Chapman Yufeng Ge Benoit de Solan Yanfeng Ding Frédéric Baret 《Plant Phenomics》 SCIE EI CSCD 2023年第2期226-238,共13页
The number of leaves at a given time is important to characterize plant growth and development.In this work,we developed a high-throughput method to count the number of leaves by detecting leaf tips in RGB images.The ... The number of leaves at a given time is important to characterize plant growth and development.In this work,we developed a high-throughput method to count the number of leaves by detecting leaf tips in RGB images.The digital plant phenotyping platform was used to simulate a large and diverse dataset of RGB images and corresponding leaf tip labels of wheat plants at seedling stages(150,000 images with over 2 million labels).The realism of the images was then improved using domain adaptation methods before training deep learning models.The results demonstrate the efficiency of the proposed method evaluated on a diverse test dataset,collecting measurements from 5 countries obtained under different environments,growth stages,and lighting conditions with different cameras(450 images with over 2,162 labels).Among the 6 combinations of deep learning models and domain adaptation techniques,the Faster-RCNN model with cycle-consistent generative adversarial network adaptation technique provided the best performance(R^(2)=0.94,root mean square error=8.7).Complementary studies show that it is essential to simulate images with sufficient realism(background,leaf texture,and lighting conditions)before applying domain adaptation techniques.Furthermore,the spatial resolution should be better than 0.6 mm per pixel to identify leaf tips.The method is claimed to be self-supervised since no manual labeling is required for model training.The self-supervised phenotyping approach developed here offers great potential for addressing a wide range of plant phenotyping problems.The trained networks are available at https://github.com/YinglunLi/Wheat-leaf-tip-detection. 展开更多
关键词 WHEAT SEEDLING PLANT
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A Bibliometric Visualization Review of the MODIS LAI/FPAR Products from 1995 to 2020 被引量:2
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作者 Kai Yan Dongxiao Zou +5 位作者 Guangjian Yan Hongliang Fang Marie Weiss Miina Rautiainen Yuri Knyazikhin Ranga B.Myneni 《Journal of Remote Sensing》 2021年第1期74-93,共20页
The MODIS LAI/FPAR products have been widely used in various fields since their first public release in 2000.This review intends to summarize the history,development trends,scientific collaborations,disciplines involv... The MODIS LAI/FPAR products have been widely used in various fields since their first public release in 2000.This review intends to summarize the history,development trends,scientific collaborations,disciplines involved,and research hotspots of these products.Its aim is to intrigue researchers and stimulate new research direction.Based on literature data from the Web of Science(WOS)and associated funding information,we conducted a bibliometric visualization review of the MODIS LAI/FPAR products from 1995 to 2020 using bibliometric and social network analysis(SNA)methods.We drew the following conclusions:(1)research based on the MODIS LAI/FPAR shows an upward trend with a multiyear average growth rate of 24.9%in the number of publications.(2)Researchers from China and the USA are the backbone of this research area,among which the Chinese Academy of Sciences(CAS)is the core research institution.(3)Research based on the MODIS LAI/FPAR covers a wide range of disciplines but mainly focus on environmental science and ecology.(4)Ecology,crop production estimation,algorithm improvement,and validation are the hotspots of these studies.(5)Broadening the research field,improving the algorithms,and overcoming existing difficulties in heterogeneous surface,scale effects,and complex terrains will be the trend of future research.Our work provides a clear view of the development of the MODIS LAI/FPAR products and valuable information for scholars to broaden their research fields. 展开更多
关键词 FPAR BACKBONE estimation
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Exploring Seasonal and Circadian Rhythms in Structural Traits of Field Maize from LiDAR Time Series 被引量:9
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作者 Shichao Jin Yanjun Su +9 位作者 Yongguang Zhang Shilin Song Qing Li Zhonghua Liu Qin Ma Yan Ge LingLi Liu Yanfeng Ding Frédéric Baret Qinghua Guo 《Plant Phenomics》 SCIE 2021年第1期389-403,共15页
Plant growth rhythm in structural traits is important for better understanding plant response to the ever-changing environment.Terrestrial laser scanning(TLS)is a well-suited tool to study structural rhythm under fiel... Plant growth rhythm in structural traits is important for better understanding plant response to the ever-changing environment.Terrestrial laser scanning(TLS)is a well-suited tool to study structural rhythm under field conditions.Recent studies have used TLS to describe the structural rhythm of trees,but no consistent patterns have been drawn.Meanwhile,whether TLS can capture structural rhythm in crops is unclear.Here,we aim to explore the seasonal and circadian rhythms in maize structural traits at both the plant and leaf levels from time-series TLS.The seasonal rhythm was studied using TLS data collected at four key growth periods,including jointing,bell-mouthed,heading,and maturity periods.Circadian rhythms were explored by using TLS data acquired around every 2 hours in a whole day under standard and cold stress conditions.Results showed that TLS can quantify the seasonal and circadian rhythm in structural traits at both plant and leaf levels.(1)Leaf inclination angle decreased significantly between the jointing stage and bell-mouthed stage.Leaf azimuth was stable after the jointing stage.(2)Some individual-level structural rhythms(e.g.,azimuth and projected leaf area/PLA)were consistent with leaf-level structural rhythms.(3)The circadian rhythms of some traits(e.g.,PLA)were not consistent under standard and cold stress conditions.(4)Environmental factors showed better correlations with leaf traits under cold stress than standard conditions.Temperature was the most important factor that significantly correlated with all leaf traits except leaf azimuth.This study highlights the potential of time-series TLS in studying outdoor agricultural chronobiology. 展开更多
关键词 CROPS HEADING TRAITS
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Global Wheat Head Detection(GWHD)Dataset:A Large and Diverse Dataset of High-Resolution RGB-Labelled Images to Develop and Benchmark Wheat Head Detection Methods 被引量:22
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作者 Etienne David Simon Madec +14 位作者 Pouria Sadeghi-Tehran Helge Aasen Bangyou Zheng Shouyang Liu Norbert Kirchgessner Goro Ishikawa Koichi Nagasawa Minhajul A.Badhon Curtis Pozniak Benoit de Solan Andreas Hund Scott C.Chapman Frédéric Baret Ian Stavness Wei Guo 《Plant Phenomics》 2020年第1期243-254,共12页
The detection of wheat heads in plant images is an important task for estimating pertinent wheat traits including head population density and head characteristics such as health,size,maturity stage,and the presence of... The detection of wheat heads in plant images is an important task for estimating pertinent wheat traits including head population density and head characteristics such as health,size,maturity stage,and the presence of awns.Several studies have developed methods for wheat head detection from high-resolution RGB imagery based on machine learning algorithms.However,these methods have generally been calibrated and validated on limited datasets.High variability in observational conditions,genotypic differences,development stages,and head orientation makes wheat head detection a challenge for computer vision.Further,possible blurring due to motion or wind and overlap between heads for dense populations make this task even more complex.Through a joint international collaborative effort,we have built a large,diverse,and well-labelled dataset of wheat images,called the Global Wheat Head Detection(GWHD)dataset.It contains 4700 high-resolution RGB images and 190000 labelled wheat heads collected from several countries around the world at different growth stages with a wide range of genotypes.Guidelines for image acquisition,associating minimum metadata to respect FAIR principles,and consistent head labelling methods are proposed when developing new head detection datasets.The GWHD dataset is publicly available at http://www.global-wheat.com/and aimed at developing and benchmarking methods for wheat head detection. 展开更多
关键词 WHEAT WHEAT MATURITY
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Global Wheat Head Detection Challenges:Winning Models and Application for Head Counting
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作者 Etienne David Franklin Ogidi +5 位作者 Daniel Smith Scott Chapman Benoit de Solan Wei Guo Frederic Baret Ian Stavness 《Plant Phenomics》 SCIE EI CSCD 2023年第3期460-473,共14页
Data competitions have become a popular approach to crowdsource new data analysis methods for general and specialized data science problems.Data competitions have a rich history in plant phenotyping,and new outdoor fi... Data competitions have become a popular approach to crowdsource new data analysis methods for general and specialized data science problems.Data competitions have a rich history in plant phenotyping,and new outdoor field datasets have the potential to embrace solutions across research and commercial applications.We developed the Global Wheat Challenge as a generalization competition in 2020 and 2021 to find more robust solutions for wheat head detection using field images from different regions.We analyze the winning challenge solutions in terms of their robustness when applied to new datasets.We found that the design of the competition had an influence on the selection of winning solutions and provide recommendations for future competitions to encourage the selection of more robust solutions. 展开更多
关键词 WHEAT specialized COMPETITION
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LiDAR Is Effective in Characterizing Vine Growth and Detecting Associated Genetic Loci
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作者 Elsa Chedid Komlan Avia +8 位作者 Vincent Dumas Lionel Ley Nicolas Reibel Gisèle Butterlin Maxime Soma Raul Lopez-Lozano Frédéric Baret Didier Merdinoglu Éric Duchêne 《Plant Phenomics》 SCIE EI CSCD 2023年第4期836-851,共16页
The strong societal demand to reduce pesticide use and adaptation to climate change challenges the capacities of phenotyping new varieties in the vineyard.High-throughput phenotyping is a way to obtain meaningful and ... The strong societal demand to reduce pesticide use and adaptation to climate change challenges the capacities of phenotyping new varieties in the vineyard.High-throughput phenotyping is a way to obtain meaningful and reliable information on hundreds of genotypes in a limited period.We evaluated traits related to growth in 209 genotypes from an interspecific grapevine biparental cross,between IJ119,a local genitor,and Divona,both in summer and in winter,using several methods:fresh pruning wood weight,exposed leaf area calculated from digital images,leaf chlorophyll concentration,and LiDAR-derived apparent volumes.Using high-density genetic information obtained by the genotyping by sequencing technology(GBS),we detected 6 regions of the grapevine genome[quantitative trait loci(QTL)]associated with the variations of the traits in the progeny.The detection of statistically significant QTLs,as well as correlations(R^(2))with traditional methods above 0.46,shows that LiDAR technology is effective in characterizing the growth features of the grapevine.Heritabilities calculated with LiDAR-derived total canopy and pruning wood volumes were high,above 0.66,and stable between growing seasons.These variables provided genetic models explaining up to 47%of the phenotypic variance,which were better than models obtained with the exposed leaf area estimated from images and the destructive pruning weight measurements.Our results highlight the relevance of LiDAR-derived traits for characterizing genetically induced differences in grapevine growth and open new perspectives for high-throughput phenotyping of grapevines in the vineyard. 展开更多
关键词 LIDAR TRAITS hundreds
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