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Observer error in vegetation surveys:a review

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Journal of Plant Ecology 2016年第4期9卷 367-379页

作者： lloyd w.morrison Department of Biology Missouri State University901 S.National AvenueSpringfieldMO 65897USA National Park Service Heartland Inventory and Monitoring Program6424 W.Farm Road 182RepublicMO 65738USA

Aims Vegetation sampling employing observers is prone to both inter-observer and intra-observer *** types of errors are common:(i)overlooking error(*** observing species actually present),(ii)misidentification error(*** correctly identifying species)and(iii)estimation error(*** accurately estimating abundance).I conducted a literature review of 59 articles that provided quantitative estimates or statistical inferences regarding observer error in vegetation *** FindingsAlmost all studies(92%)that tested for a statistically significant effect of observer error found at least one significant *** surveys of species composition,mean pseudoturnover(the percentage of species overlooked by one observer but not another)was 10-30%.Species misidentification rates were on the order of 5-10%.The mean coefficient of variation(CV)among observers in surveys of vegetation cover was often several hundred%for species with low cover,although CVs of 25-50%were more representative of species with mean covers of>50%.A variety of metrics and indices(including commonly used diversity indices)and multivariate data analysis techniques(including ordinations and classifications)were found to be sensitive to observer *** of error commonly include both characteristics of the vegetation(*** size of populations,rarity,morphology,phenology)and attributes of the observers(*** fatigue,personal biases,differences in experience,physical stress).The use of multiple observers,additional training including active feedback approaches,and continual evaluation and calibration among observers are recommended as strategies to reduce observer error in vegetation surveys.

关键词： interobserver error intraobserver error misidentification pseudoturnover vegetation sampling

草地植被调查中的观测者误差:物种多样性指标和物种丰度关系的影响

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植物生态学报(英文版) 2023年第4期16卷 36-48页

作者： lloyd w.morrison Sherry A.Leis Michael D.DeBacker Department of Biology Missouri State UniversityMO 65897USA National Park Service Heartland Inventory and Monitoring ProgramWilson’s Creek National BattlefieldMO 65738USA

我们研究了观察者误差对4种常用物种多样性度量的影响:物种丰富度、香农-威纳多样性指数、香农-威纳均匀度指数和辛普森多样性指数。我们还评估了观察者误差如何影响由非度量多维尺度(NMS)排序确定的物种丰度关系的多变量分析得出的推论... 详细信息

我们研究了观察者误差对4种常用物种多样性度量的影响:物种丰富度、香农-威纳多样性指数、香农-威纳均匀度指数和辛普森多样性指数。我们还评估了观察者误差如何影响由非度量多维尺度(NMS)排序确定的物种丰度关系的多变量分析得出的推论。3位不同的植物学家在美国密苏里州和堪萨斯州的两个国家公园对草原植被进行了采样。其中的两名植物学家对相同的地块进行了采样,编制了物种组成清单并估计了叶面覆盖率,然后比较了数据记录的差异。伪转换率(即由于观察者错误导致的表观转换率)在17.1%到22.1%之间,覆盖类别估计的差异在21.5%到30.5%之间。观察者对物种多样性测量值的百分比差异取决于数据的总结方式,但总是<20%,而且通常<10%。基于这些研究结果,与周转指数相比,物种多样性指标受观察者误差的影响相对较小。然而,周转指数包含更多信息,因为它们追踪的是单个物种,而在大多数物种多样性指数中,物种是可以互换的。因此,由于物种多样性指数的计算方式,识别出的错误较少。NMS排序显示,虽然不同观察者对某些地块的描述相似,但观察者对其他地块的记录之间的差异导致排序空间的分离更大。与另一个观察者相比,代表一个观察者记录的点通常在相同方向上在排序空间中移动。

关键词：估计误差观察者误差伪周转率物种多样性度量排序植被调查

Interobserver error in grassland vegetation surveys:sources and implications

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Journal of Plant Ecology 2020年第5期13卷 641-648页

作者： lloyd w.morrison Sherry A.Leis Michael D.DeBacker Department of Biology Missouri State University901 S.National AvenueSpringfieldMO 65897USA National Park Service Heartland Inventory and Monitoring ProgramWilson’s Creek National Battlefield6424 W.Farm Road 182RepublicMO 65738USA

人类观测误差是植被测量中不可避免的一个问题。我们量化了与高草草原植被长期监测相关的观测者间误差的四个组成部分:忽略误差、误识别误差、谨慎误差和估计误差。由于观察者会产生误差,我们还评估了地块大小与伪周转率的关系,以及对... 详细信息

人类观测误差是植被测量中不可避免的一个问题。我们量化了与高草草原植被长期监测相关的观测者间误差的四个组成部分:忽略误差、误识别误差、谨慎误差和估计误差。由于观察者会产生误差,我们还评估了地块大小与伪周转率的关系,以及对比了物种组成和丰度的伪变化与四年间植被变化之间的关系。这项研究是在美国堪萨斯州的高草草原国家保护区进行的。监测点包括10个地块,每个地块由一系列的四个嵌套框架(0.01,0.1,1和10 m^(2))组成。在每个嵌套框架中记录了所有的草本物种,并且在10 m^(2)的空间尺度下,视觉估计了7个覆盖类别内的叶面覆盖。总共调查了300个地块(30个地点),并随机选择28个地块重新进行测量以评估观测者的误差。所有的调查由四名观测者分两组完成。研究结果表明,在10 m^(2)空间尺度上,由忽略误差引起的伪周转率平均为18.6%,而由误识别误差和谨慎误差引起的伪周转率平均值分别为1.4%和0.6%。尽管由重新定位引起的误差可能也起一定的作用,由忽略误差导致的伪周转率随样地面积的减小而增加。物种组成在四年期间的变化(排除潜在的误识别误差和谨慎误差)为30.7%,其中包括由忽略误差和实际变化引起的伪周转率。18.6%的忽略误差表明四年期间的实际变化只有12.1%。对于估计误差,26.2%会记录为不同的覆盖等级。在四年的时间内,46.9%的记录显示了不同的覆盖等级,这表明两个时间段间覆盖率变化的56%是由于观测者误差造成的。

关键词：谨慎误差估计误差误识别误差观测者误差忽略误差伪周转率

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全球红火蚁扩张范围预测

中华卫生杀虫药械 2006年第1期12卷 22-26页

作者： lloyd w.morrison 郑剑宁宋晔晔裘炯良薛新春宁波出入境检验检疫局浙江宁波315012

在众多入侵生物中,外来蚂蚁是最棘手的生物之一.许多蚂蚁种群,尤其是那些热带或亚热带的蚂蚁种群,很容易通过人类的商业活动而被迁移到世界各地(McGlynn,1999).其中一些种类已经被证实对侵入区域的自然动物群体产生了广泛而有害的影响(... 详细信息

在众多入侵生物中,外来蚂蚁是最棘手的生物之一.许多蚂蚁种群,尤其是那些热带或亚热带的蚂蚁种群,很容易通过人类的商业活动而被迁移到世界各地(McGlynn,1999).其中一些种类已经被证实对侵入区域的自然动物群体产生了广泛而有害的影响(如 Vander Meer等,1990;williams,1994;Human和Gordon,1997;Jourdan,1997;Holway,1998;Vanderwoude等,2000的报道).

关键词： williams 预测扩张火蚁全球 Gordon Human 世界各地商业活动

Fragipan Horizon Changes Using Annual Ryegrass and Other Admendments

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Open Journal of Soil Science 2024年第6期14卷 388-397页

作者： lloyd Murdock Anastasios Karathanasis Dottie Call Dana L. Dinnes Amitava Chatterjee Department of Plant & Soil Science University of Kentucky Lexington KY USA USDA-ARS National Laboratory for Agriculture and the Environment University Bldg Ames IA USA

A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received several treatments with various amendments for different periods ranging from 9 to 17 months. The amendments included annual ryegrass or Festulolium residues, powder limestone and various humate compounds alone or in combination with the grass residues. The results suggested a significant effect of ryegrass and Festulolium in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particularly when used in combination with certain humate materials such as Leonardite. Apparently, this is the result of the release of certain soluble organic compounds from the plant residues or the humate amendments that increase the solubility of Si and Al associated with the fragipan brittleness, thus decreasing the density of the compacted fragipan material.

关键词： Fragipan Fragipan Horizon Fragipan Soils Changing the Fragipan Annual Ryegrass Changes Fragipan Festulolium Changes Fragipan Amendments That Change the Fragipan

坦桑尼亚梅拉尼坦桑石矿床地质特征及成因模式

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世界地质 2024年第3期43卷 353-362页

作者：孙国锋张明云闫红圃张猛张伟杰 lloyd Shawarira 河南省地质研究院郑州450001 河南省第二地质勘查院有限公司郑州450046 中金国检珠宝玉石质量检验中心有限公司广东深圳518020 津巴布韦地质调查局津巴布韦哈拉雷ZW192201

通过野外实地矿区地质填图,对坦桑尼亚梅拉尼坦桑石矿床的地质背景及矿区矿床地质特征进行详细描述,尤其对矿体及矿物宝石学特征进行了剖析和综述,探讨了宝石成因模式。认为坦桑石形成于约5亿年前的泛非运动,仅产于新元古代莫桑比克变... 详细信息

通过野外实地矿区地质填图,对坦桑尼亚梅拉尼坦桑石矿床的地质背景及矿区矿床地质特征进行详细描述,尤其对矿体及矿物宝石学特征进行了剖析和综述,探讨了宝石成因模式。认为坦桑石形成于约5亿年前的泛非运动,仅产于新元古代莫桑比克变质带的蚀变石墨片麻岩中,属于接触交代成因的矽卡岩矿床,主要受地层岩性和构造变形两个因素控制。

关键词：矽卡岩地质特征坦桑石成因模式梅拉尼

Arabidopsis Mutants and the Network of M icrotu bu le-Associated Functions

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Molecular Plant 2008年第6期1卷 888-898页

作者： Henrik Buschmann Clive w. lloyd Department of Cell and Developmental Biology John Innes Centre 1 Colney Lane Norwich NR4 7UH UK

In early eukaryotes, the microtubule system was engaged in mitosis, intracellular transport, and flagellumbased motility. In the plant lineage, the evolution of a multicellular body involved the conservation of some core functions, the loss of others, and the elaboration of new microtubule functions associated with the multicellular plant habit. This diversification is reflected by the presence of both conserved （animal/fungi-like） and novel （plant-like） sequences encoding microtubule-related functions in the Arabidopsis genome. The collection of microtubule mutants has grown rapidly over recent years. These mutants present a wide range of phenotypes, consistent with the hypothesis of a functional diversification of the microtubule system. In this review, we focus on mutant analysis and, in particular, discuss double mutant analysis as a valuable tool for pinpointing pathways of gene function. A future challenge will be to define the complete network of genetic and physical interactions of microtubule function in plants. In addition to reviewing recent progress in the functional analysis of the ＇MAPome＇, we present an online database of Arabidopsis mutants impaired in microtubule functions.

关键词： cell division cell morphogenesis cytoskeleton genetics development Arabidopsis.

Unsupervised ore/waste classification on open-cut mine faces using close-range hyperspectral data

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Geoscience Frontiers 2023年第4期14卷 89-99页

作者： lloyd windrim Arman Melkumyan Richard J.Murphy Anna Chlingaryan Raymond Leung Rio Tinto Centre for Mine Automation Australian Centre for Field RoboticsThe University of SydneySydney 2006Australia

The remote mapping of minerals and discrimination of ore and waste on surfaces are important tasks for geological applications such as those in *** tasks have become possible using ground-based,close-range hyperspectral sensors which can remotely measure the reflectance properties of the environ-ment with high spatial and spectral ***,autonomous mapping of mineral spectra mea-sured on an open-cut mine face remains a challenging problem due to the subtleness of differences in spectral absorption features between mineral and rock classes as well as variability in the illumination of the *** additional layer of difficulty arises when there is no annotated data available to train a supervised learning algorithm.A pipeline for unsupervised mapping of spectra on a mine face is pro-posed which draws from several recent advances in the hyperspectral machine learning *** proposed pipeline brings together unsupervised and self-supervised algorithms in a unified system to map minerals on a mine face without the need for human-annotated training *** pipeline is eval-uated with a hyperspectral image dataset of an open-cut mine face comprising mineral ore martite and non-mineralised *** combined system is shown to produce a superior map to its constituent algo-rithms,and the consistency of its mapping capability is demonstrated using data acquired at two differ-ent times of day.

关键词： Hyperspectral imaging Mineral mapping Open-cut mine face Machine learning Convolutional neural networks Illumination invariance

The Utilization of the Generating Function Technique in the Discovery of Solutions for the Three-Dimensional Navier-Stokes Equation System

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Open Journal of Fluid Dynamics 2022年第1期12卷 86-95页

作者： Robert lloyd Jackson Independent Researcher Stilwell KS USA

The derivation of solutions to the Navier-Stokes (system of) equations (NSEs), in three spatial dimensions, has been an enigma as time can tell. This study wishes to show how to eradicate this problem via the usage of a recently proposed method for solving partial differential equations called the Generating Function Technique, or GFT for short. The paper will first quickly define the NSEs with and without an external force, then provide a quick synopsis of the GFT. Next, the study will derive solutions to these two major problems and give an analysis of the data concerning a specific set of criteria established by the Clay Mathematics Institute to determine the smoothness and existence of solutions. Results via GFT will show one can easily prove the existence of solutions to the NSEs with or without the presence of an external force. However, only the solutions to the NSEs will be globally bound.

关键词： Physics and Mathematics Fluid Mechanics Partial Differential Equations