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FSPM-P: towards a general functional-structural plant model for robust and comprehensive model development 被引量:6
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作者 Michael HENKE Winfried KURTH Gerhard H. BUCK-SORLIN 《Frontiers of Computer Science》 SCIE EI CSCD 2016年第6期1103-1117,共15页
In the last decade, functional-structural plant modelling (FSPM) has become a more widely accepted paradigm in crop and tree production, as 3D models for the most important crops have been proposed. Given the wider ... In the last decade, functional-structural plant modelling (FSPM) has become a more widely accepted paradigm in crop and tree production, as 3D models for the most important crops have been proposed. Given the wider portfolio of available models, it is now appropriate to enter the next level in FSPM development, by introducing more efficient methods for model development. This includes the consideration of model reuse (by modularisafion), combination and comparison, and the enhancement of existing mod- els. To facilitate this process, standards for design and communication need to be defined and established. We present a first step towards an efficient and general, i.e., not speciesspecific FSPM, presently restricted to annual or bi-annual plants, but with the potential for extension and further generalization. Model structure is hierarchical and object-oriented, with plant organs being the base-level objects and plant individual and canopy the higher-level objects. Modules for the majority of physiological processes are incorporated, more than in other platforms that have a similar aim (e.g., photosynthesis, organ formation and growth). Simulation runs with several general parameter sets adopted from the literature show that the present prototype was able to reproduce a plausible output range for different crops (rapeseed, barley, etc.) in terms of both the dynamics and final values (at harvest time) of model state variables such as assimilate production, organ biomass, leaf area and architecture. 展开更多
关键词 functional-structural plant model prototyping modelling standards teaching / learning FSPM GroIMP
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Predicting potential suitable areas of Orchidaceae plants with national key reserve from Heilongjiang province in MaxEnt models
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作者 Weixue Zhong Xiaoxue Wei +6 位作者 Yujia Yu Xiaoqing Tang Ye Zhang Xinyu Huang Xiaohui Li Ying Liu Dewen Li 《Ecological Frontiers》 2026年第1期18-28,共11页
The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and ... The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and 19 bioclimatic variables were selected,and the environmental factors required for modeling were screened out by pearson correlation analysis and variance inflation factor(VIF)analysis.The potential suitable areas of Orchidaceae plants were predictat present and under different climate scenarios in 2090s by using geographic information system(GIS)and Maximum Entropy Model(MaxEnt).And then evaluated the prediction accuracy of the MaxEnt model using the AUC value,the TSS value and the Kappa value.The results showed that:1)The area under curve(AUC)values,true skill statistics(TSS)values and KAPPA values predicted by MaxEnt model were separately above 0.9,0.85 and 0.75.2)Under the climate scenario at present,the total suitable area of Orchidaceae plants was about 9.61×10^(6)km^(2),which was mainly distributed in Heilongjiang province.Among them,the high-suitable area of Cypripedium shanxiense S.C.Chen was the largest,the non-suitable area of Cypripedium guttatum Sw was the largest.3)Under different climate scenarios in 2090s,the total suitable area was slightly increasing(9.62×10^(6)km^(2)).Among them,Cypripedium shanxiense S.C.Chen and Gastrodiae Rhizoma both showed the trend of expansion to the southwest,China,and the suitable areas expanded significantly.Comprehensive factor analysis showed that temperature and precipitation were the main bioclimatic variables of suitable areas distribution,and the low emission scenario(SSP 2-4.5)will be more conducive to the survival of Orchidaceae plants. 展开更多
关键词 Orchidaceae plants Potential suitable areas Bioclimatic variables MaxEnt models National key reserve
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A Functional-Structural Model of Rice Seedling Coupled with Nitrogen Metabolism 被引量:1
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作者 Zhuoyang Yusang Lifeng Xu +2 位作者 Weilong Ding Zhangyun Yi Yunwei Qiu 《Journal of Agricultural Science and Technology(B)》 2014年第8期652-660,共9页
With the ability of representing the association and inner-feedback between plant morphological structure and physiological functions, functional-structural plant modeling (FSPM) approach has been used in many works... With the ability of representing the association and inner-feedback between plant morphological structure and physiological functions, functional-structural plant modeling (FSPM) approach has been used in many works, trying to better understand the mechanisms of integrating plant functions and its structure, and their communication with environmental factors. To do so, an FSPM of rice seedling was developed in this study, including structural morphogenetic model, photosynthetic model and biomass partitioning module. It can thus describe the developmental course of the rice structure dynamically based on the processes of biomass producing and partitioning. Furthermore, the processes of nitrogen metabolism, which influence the N content and growth dynamics of the virtual rice, were also considered. The model was developed with L-system on a platform established with Java programming language, which took over the parsing and visualization of the L-system strings to 3D objects using Java 3D extended library. The physiological processes in the model can be modified and further improved to gradually meet the needs for modeling the whole life cycle of rice, e.g., considering the respiration, and interaction with other environmental factors like CO2, temperature, etc.. The model was developed to provide a platform to systematically study and understand how plant systems like rice seedling work. The model and the virtualization platform can be expanded to provide decision support on N fertilizer application for the rice seedling and the other crops. 展开更多
关键词 functional-structural plant model rice seedling nitrogen metabolism L-SYSTEM VISUALIZATION plant model.
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Flammability of plant communities in arid and semi-arid ecosystems: Identifying key drivers and management implications
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作者 Mosayeb HOJATI Azam KHOSRAVI MASHIZI 《Journal of Arid Land》 2026年第2期304-321,共18页
Arid and semi-arid ecosystems are prone to extensive fires due to specific climatic conditions,sparse vegetation cover,and high density of fine fuels.Understanding the flammability characteristics of land covers is es... Arid and semi-arid ecosystems are prone to extensive fires due to specific climatic conditions,sparse vegetation cover,and high density of fine fuels.Understanding the flammability characteristics of land covers is essential for fire management and designing land restoration programs in arid and semi-arid ecosystems.This study provided a new approach to evaluate the flammability of shrublands and woodlands using flammability indices(FIs)including time to ignition(TI),duration of combustion(DC),and flame height(FH)of plant species and their relative frequencies in the Dalfard Basin of southeastern Iran.The results showed that there was a significant difference in FIs between land covers.Shrublands had higher flammability potential compared with woodlands.Plant moisture content had a negative relationship with TI(P<0.010)and no significant relationship with DC and FH(P>0.050).Artemisia spp.,Astragalus gossypinus Fischer,Amygdalus scoparia Spach,and Cymbopogon jwarancusa(Jones)Schult.had the highest FI.Tree species such as Rhazya stricta Decne.,and Pistacia atlantica Desf.showed greater resistance to fire.Using principal component analysis,the relationship between species and FIs was examined,and TI of wet fuel was the most important FI in relation to species.Structural equation model showed that life form(P<0.001)was the most important flammability driver.Precipitation(P<0.010)and legume species(P<0.010)were significantly related to the flammability in arid land.This study emphasizes the importance of managing high-risk species and using resistant species in vegetation restoration and shows that combining species FIs with their abundance is an effective tool for assessing fire risk and fuel management at the plant community scale. 展开更多
关键词 duration of combustion plant moisture fire management structural equation model arid ecosystems
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Understory floristic composition of planted western white pine stands in the northern Rocky Mountains
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作者 Andrew S.Nelson Theresa B.Jain +3 位作者 Jason Reinhardt Eva K.Strand Nicole Mutchler John Byrne 《Forest Ecosystems》 2026年第1期109-119,共11页
Understory plants are an integral part of forests,serving a variety of functions that help maintain healthy ecosystems.The structure and composition of the understory are influenced by numerous biotic and abiotic fact... Understory plants are an integral part of forests,serving a variety of functions that help maintain healthy ecosystems.The structure and composition of the understory are influenced by numerous biotic and abiotic factors,with light being critical.The introduction of the pathogen Cronartium ribicola,which causes white pine blister rust,into North America in the early 20 th century led to the near total loss of western white pine(Pinus monticola)from moist forests of the Northern Rockies.Management is reintroducing blister rust-resistant western white pine across the landscape,but the effects on the understory are unknown.We examined the effects of stand structure and proportion of western white pine in the overstory on understory diversity of vascular plants in closed canopy stands dominated by blister rust-resistant western white pine across northern Idaho.Habitat series explained the greatest amount of variation(34%)in species presence-absence,while canopy cover accounted for 25%,basal area of all trees for 18%,and the proportion of western white pine composition by 14%.Our analysis revealed positive relationships between the proportion of western white pine in the overstory and both the presence of understory plants and the cover of several understory species.For both the presence and cover,separate sets of thirteen species were found to have a positive relationship with the proportion of western white pine in the overstory,with eight species in common.This research fills a knowledge gap by using data from a range of stands across northern Idaho with varying abundance of western white pine in the overstory to evaluate the relationship between the understory and overstory composition.As land managers plant more western white pine trees,we are likely to see the concomitant increase in understory plant diversity across the landscape,in addition to numerous other benefits,including disturbance resistance and resilience. 展开更多
关键词 Moist conifer forests Understory composition plant communities BIODIVERSITY Foundational species Hierarchical modeling of species communities
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Identification of dominant plant water-use strategies in arid zones under deuterium depletion conditions
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作者 DAI Ningze SHI Fengzhi +3 位作者 WANG Yuehui YAO Peng ZHU Jianting ZHAO Chengyi 《Journal of Arid Land》 2026年第4期676-695,共20页
Identifying plant water sources is fundamental for elucidating ecohydrological processes and improving water resource management in arid zones under climate change.Stable hydrogen and oxygen isotopes are commonly used... Identifying plant water sources is fundamental for elucidating ecohydrological processes and improving water resource management in arid zones under climate change.Stable hydrogen and oxygen isotopes are commonly used to trace plant water uptake;however,cryogenic vacuum extraction(CVE),the standard method for extracting plant xylem water,may induce deuterium depletion,thereby biasing source attribution.To systematically assess the effects of CVE-induced deuterium depletion across species,size classes,and habitats,we excavated five representative soil profiles along the mainstream of the Tarim River in northwestern China,in mid-July 2022.A total of 29 individuals,comprising both Populus euphratica and Tamarix ramosissima,were sampled.We divided P.euphratica individuals into four groups based on diameter at breast height(<50,50-100,100-250,and>250 cm),while categorized T.ramosissima individuals into four groups according to plant height(<1.0,1.0-2.0,2.0-4.0,and>4.0 m).Plant xylem water was extracted using CVE,and five deuterium depletion scenarios(-5.00‰,-7.00‰,-9.00‰,-11.00‰,and-13.00‰)were simulated.The Bayesian Mixing Model for Stable Isotope Analysis in R(MixSIAR)was applied under six input modes to quantify the proportional contributions of potential water sources and associated prediction errors.Model evaluation revealed that P.euphratica achieved the highest accuracy with a-9.00‰correction of depletion,whereas a-11.00‰ correction was optimal for T.ramosissima,reducing relative prediction errors by 68.65%and 67.73%,respectively,compared with uncorrected scenario.Small-sized P.euphratica individuals exhibited less deuterium depletion,whereas no clear size-dependent pattern was observed for T.ramosissima.Spatially,plant individuals located farther from the river exhibited reduced deuterium depletion in xylem water.Despite differences in species traits and habitat conditions,both species predominantly relied on deep soil water and groundwater,which together contributed,on average,61.45%and 59.95%for P.euphratica and T.ramosissima,respectively.These findings highlight the necessity of accounting for CVE-induced deuterium depletion when identifying plant water-use strategies and provide methodological guidance for isotope-based ecohydrological studies in arid environments. 展开更多
关键词 plant water uptake hydrogen isotopes oxygen isotopes cryogenic vacuum extraction(CVE) deuterium depletion Bayesian Mixing model for Stable Isotope Analysis in R(MixSIAR) Tarim River Basin
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Construction of Early-warning Model for Plant Diseases and Pests Based on Improved Neural Network 被引量:2
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作者 曹志勇 邱靖 +1 位作者 曹志娟 杨毅 《Agricultural Science & Technology》 CAS 2009年第6期135-137,154,共4页
By studying principles and methods related to early-warning model of plant diseases and using PSO method, parameter optimization was conducted to backward propagation neural network, and a pre-warning model for plant ... By studying principles and methods related to early-warning model of plant diseases and using PSO method, parameter optimization was conducted to backward propagation neural network, and a pre-warning model for plant diseases based on particle swarm and neural network algorithm was established. The test results showed that the construction of early-warning model is effective and feasible, which will provide a via- ble model structure to establish the effective early-warning platform. 展开更多
关键词 Backward propagation neural network Particle swarm algorithm plant diseases and pests Early-warning model
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Virtual Plant Modeling Based on Mutual Feedback of Function-structure 被引量:1
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作者 范振岐 司春景 +2 位作者 曹洪武 韩旭 李文华 《Agricultural Science & Technology》 CAS 2011年第12期1972-1974,共3页
[Objective] To study virtual plant modeling based on mutual feedback of function-structure.[Method] With the analysis of the shortcomings of current virtual plant modeling method,the modeling with the idea of function... [Objective] To study virtual plant modeling based on mutual feedback of function-structure.[Method] With the analysis of the shortcomings of current virtual plant modeling method,the modeling with the idea of function-structure mutual feedback was put forward,and the steps of this modeling were elaborated,including the determination of morphological structure model,biomass production model,biomass allocation model,organ reconstruction model,and the integration method of function model and morphological structure model.[Results] The breakthrough of function-structure mutual feedback based mechanism from the boundaries of physiological ecology model and morphological structure model can solve the difficulty of data transmission between the two models and build an integrated model from the two,which can effectively reflect the incidence relation between plant morphology and function,and more suitable for the growth mechanisms of plants.This modeling approach has significant advantages in the dynamic simulation of plant growth.[Conclusion] The virtual plant modeling based on function-structure mutual feedback provides basis for the simulation of plant growth status in the next stage,and has important significance for the accurate simulation of the dynamic growth process of plant. 展开更多
关键词 Structure-function model Mutual feedback mechanism Virtual plant
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MORPHOLOGICAL MODEL FOR RHEOLOGICAL PROPERTIES OF PLANT CELL SUSPENSION CULTURE SYSTEM
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作者 吴兆亮 元英进 +1 位作者 邢允 胡宗定 《Transactions of Tianjin University》 EI CAS 1999年第2期61-64,共4页
This paper puts forward a physical and mathematical model for the rheological properties of a plant cell suspension culture system.The model can explain why the system is pseudoplastic satisfactorily,thus the rheologi... This paper puts forward a physical and mathematical model for the rheological properties of a plant cell suspension culture system.The model can explain why the system is pseudoplastic satisfactorily,thus the rheological properties of the system as the effect of the flow behavior index on plant cell concentration are interpreted correctly and the mechanism of the rheological properties of the system is further understood.Therefore the model can be applied in the technological design and optimum conditions of the system and the reformation,evaluation and scale up of reactors. 展开更多
关键词 morphological model rheological property plant cell suspension culture pseudoplastic fluid
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Mathematical Model and Simulation of Harmful Invasive Plant Control
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作者 马庆功 杨波 《Agricultural Science & Technology》 CAS 2014年第12期2057-2063,共7页
Plant invasion refers to the phenomenon that some plants grow too fast due to they are far away from the original living environment or predators, affecting the local environment. With the development of tourism and t... Plant invasion refers to the phenomenon that some plants grow too fast due to they are far away from the original living environment or predators, affecting the local environment. With the development of tourism and trade, the harm caused by invasive plants will be more and more serious. Therefore, it is necessary to ex- plore an effective method for controlling plant invasion through qualitative and quan- titative research. In this paper, the models were established for the early and late harmful plant invasion control. The huge computation was completed by the com- puter programming to obtain the optimal solutions of the models. The real meaning of the optimal solution was further discussed. Through numerical simulations and discussion, it could be concluded that the quantitative research on the invasive plant control had a certain application value. 展开更多
关键词 Invasive plant Linear programming model Logistic model Pontryagin minimum principle Numerical simulation
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对《Plant Growth Modeling and Applications》一书的评介
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作者 熊范伦 《自动化学报》 EI CSCD 北大核心 2004年第3期F002-F002,共1页
农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性... 农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性弱点,提高农业生产者和管理者的素质和能力.农业信息化近些年来在我国有了快速的发展.2003年12月10日,我国科技部863计划支持的重大专项"智能化农业信息技术应用示范工程"(俗称"电脑农业")荣获世界信息峰会全球大奖,标志着中国在农业专家系统和智能化农业信息技术应用方面取得了重大成就. 展开更多
关键词 plant GROWTH modeling and Applications》 农业信息技术 书评 “电脑农业” 中国 智能化农业信息技术
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Model Selection of Gas Turbine for Large Scale Gas-Fired Combined Cycle Power Plant
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作者 何语平 《Electricity》 2003年第4期36-39,共4页
This paper briefs the configuration and performance of large size gas turbines and their composed combined cycle power plants designed and produced by four large renown gas turbine manufacturing firms in the world, pr... This paper briefs the configuration and performance of large size gas turbines and their composed combined cycle power plants designed and produced by four large renown gas turbine manufacturing firms in the world, providing reference for the relevant sectors and enterprises in importing advanced gas turbines and technologies. 展开更多
关键词 natural gas combined cycle power plant unit model selection
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Integration of InVEST-habitat quality model with landscape pattern indexes to assess mountain plant biodiversity change: A case study of Bailongjiang watershed in Gansu Province 被引量:49
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作者 GONG Jie XIE Yuchu +2 位作者 CAO Erjia Huang Qiuyan LI Hongying 《Journal of Geographical Sciences》 SCIE CSCD 2019年第7期1193-1210,共18页
Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious biodiversity loss with fragile ecological problems. Even thoug... Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious biodiversity loss with fragile ecological problems. Even though increasing attentions had been paid to this issue, we still lacked efficient methods to assess the change of plant biodiversity at medium/large scale due to the poor data and co-existing multiple habitat types. This study proposed an integrated method combining InVEST-habitat quality model, NPP and landscape pattern indexes to analyze the spatial heterogeneity of plant biodiversity and its spatiotemporal change on raster cell scale. The results indicated that plant biodiversity service was high in Bailongjiang watershed with obvious spatial pattern variations. The land area containing higher plant biodiversity were 3161 km2, which mainly distributed in the National Nature Reserve and forestry area. While the areas with lower plant biodiversity accounted for 37.67% and mainly distributed in the valleys between Zhouqu-Wudu-Wenxian County, the valley of Minjiang in Tanchang County and alpine mountain snow-covered regions. During 1990–2010, plant biodiversity level tended to increase and the higher plant biodiversity area increased from 14.13% to 17.15% due to ecological restoration and afforestation, while plant biodiversity decreased in the area with intensive human activities, such as cultivated land, urban and rural land. The results showed that combining InVEST-habitat quality model, NPP and landscape pattern indexes can effective reveal mountain plant biodiversity change. The study was useful for plant biodiversity conservation policy-making and human activity management for the disaster-impacted mountainous areas in China. 展开更多
关键词 spatial CHANGE HABITAT quality landscape pattern plant BIODIVERSITY conservation: INVEST model Bailongjiang WATERSHED in GANSU Province
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Genetic control of flowering time in woody plants: Roses as an emerging model 被引量:6
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作者 Xue Dong Xiaodong Jiang +4 位作者 Guoqiang Kuang Qingbo Wang Micai Zhong Dongmin Jin Jinyong Hu 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第2期104-110,共7页
Genetic control of the timing of flowering in woody plants is complex and has yet to be adequately investigated due to their long life-cycle and difficulties in genetic modification.Studies in Populus,one of the best ... Genetic control of the timing of flowering in woody plants is complex and has yet to be adequately investigated due to their long life-cycle and difficulties in genetic modification.Studies in Populus,one of the best woody plant models,have revealed a highly conserved genetic network for flowering timing in annuals.However,traits like continuous flowering cannot be addressed with Populus.Roses and strawberries have relatively small,diploid genomes and feature enormous natural variation.With the development of new genetic populations and genomic tools,roses and strawberries have become good models for studying the molecular mechanisms underpinning the regulation of flowering in woody plants.Here,we review findings on the molecular and genetic factors controlling continuous flowering in roses and woodland strawberries.Natural variation at TFL1 orthologous genes in both roses and strawberries seems be the key plausible factor that regulates continuous flowering.However,recent efforts suggest that a two-recessive-loci model may explain the controlling of continuous flowering in roses.We propose that epigenetic factors,including non-coding RNAs or chromatin-related factors,might also play a role.Insights into the genetic control of flowering time variation in roses should benefit the development of new germplasm for woody crops and shed light on the molecular genetic bases for the production and maintenance of plant biodiversity. 展开更多
关键词 ROSE Continuous flowering model woody plant GENETICS Bulk-segregation analysis Genome-wide prediction
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Plant Temperature and Its Simulation Model of Thermo-Sensitive Genic Male Sterile Rice 被引量:7
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作者 LU Chuan-gen XIA Shi-jian +2 位作者 CHEN Jing Hu Ning YAO Ke-min 《Rice science》 SCIE 2008年第3期223-231,共9页
Plant temperature (Tp) and its relations to the microclimate of rice colony and irrigation water were studied using a thermo-sensitive genic male sterile (TGMS) rice line, Pei'ai 64S. Significant differences in t... Plant temperature (Tp) and its relations to the microclimate of rice colony and irrigation water were studied using a thermo-sensitive genic male sterile (TGMS) rice line, Pei'ai 64S. Significant differences in the daily change of temperature were detected between Tp and air temperature at the height of 150 cm (TA). From 8:00 to 20:00, Tp was lower than TA, but they were similar during 21:00 to next 7:00. The maximum Tp occurred one hour earlier than the maximum TA, though they both reached the minimum at 6:00. Tp fluctuated less than TA. At the same height, during 6:00-13:00, Tp was higher than air temperature (Ta), and Tp reached the maximum one hour earlier than Ta. During the rest time on sunny day, Tp was close to or even a little lower than Ta. On overcast day, Tp was higher than Ta in the whole day, and both maximized at the same time. In addition, Tp was regulated by solar radiation, cloudage and wind speed in daytime, and by irrigation water at night. The present study indicated that a TA of 29.6℃ was the critical point, at which Tp was increased or decreased by irrigation water. Tp and the difference between water and air temperatures showed a conic relation. Tp fluctuation was also regulated by the absorption or reflection of solar radiation by leaves during daytime and release of heat energy during nighttime. By analysis on correlation and regression simulation, two models of Tp were established. 展开更多
关键词 RICE plant temperature air temperature simulation model thermo-sensitive genic male sterility
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Kinetics of zinc sulfide concentrate direct leaching in pilot plant scale and development of semi-empirical model 被引量:7
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作者 Nima SADEGHI Javad MOGHADDAM Mehdi OJAGHI ILKHCHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第10期2272-2281,共10页
The direct leaching kinetics of an iron-poor zinc sulfide concentrate in the tubular reactor was examined.All tests werecarried out in the pilot plant.To allow the execution of hydrostatic pressure condition,the slurr... The direct leaching kinetics of an iron-poor zinc sulfide concentrate in the tubular reactor was examined.All tests werecarried out in the pilot plant.To allow the execution of hydrostatic pressure condition,the slurry with ferrous sulfate and sulfuric acidsolution was filled into a vertical tube(9m in height)and air was blown from the bottom of the reactor.The effects of initial acidconcentration,temperature,particle size,initial zinc sulfate concentration,pulp density and the concentration of Fe on the leachingkinetics were investigated.Results of the kinetic analysis indicate that direct leaching of zinc sulfide concentrate follows shrinkingcore model(SCM).This process was controlled by a chemical reaction with the apparent activation energy of49.7kJ/mol.Furthermore,a semi-empirical equation is obtained,showing that the order of the iron,sulfuric acid and zinc sulfate concentrationsand particle radius are0.982,0.189,-0.097and-0.992,respectively.Analysis of the unreacted and reacted sulfide particles bySEM-EDS shows that insensitive agitation in the reactor causes detachment of the sulfur layer from the particles surface in lowerthan60%Zn conversion and lixiviant in the face with sphalerite particles. 展开更多
关键词 KINETICS direct leaching SPHALERITE shrinking core model (SCM) pilot plant
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Numerical Analysis of Stochastic Vector Borne Plant Disease Model 被引量:6
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作者 Kamaledin Abodayeh Ali Raza +3 位作者 Muhammad Shoaib Arif Muhammad Rafiq Mairaj Bibi Rabia Fayyaz 《Computers, Materials & Continua》 SCIE EI 2020年第4期65-83,共19页
We are associating the solutions of stochastic and deterministic vector borne plant disease model in this manuscript.The dynamics of plant model depends upon threshold number P^(∗).If P^(∗)<1 then condition helpful... We are associating the solutions of stochastic and deterministic vector borne plant disease model in this manuscript.The dynamics of plant model depends upon threshold number P^(∗).If P^(∗)<1 then condition helpful to eradicate the disease in plants while P^(∗)>1 explains the persistence of disease.Inappropriately,standard numerical systems do not behave well in certain scenarios.We have been proposed a structure preserving stochastic non-standard finite difference system to analyze the behavior of model.This system is dynamical consistent,positive and bounded as defined by Mickens. 展开更多
关键词 Vector borne plant model stochastic numerical systems stability
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3D Visual Plant Models in Computational Fluid Dynamics Simulation of Ambient Wind Flow around an Isolated Tree 被引量:2
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作者 王宇荣 付海明 《Journal of Donghua University(English Edition)》 EI CAS 2017年第2期304-309,共6页
Plants can reduce the velocity of wind and wind erosion and prevent the movement of sand.But it may be extremely difficult to measure directly the aerodynamic characteristics of the airflow near the real vegetation in... Plants can reduce the velocity of wind and wind erosion and prevent the movement of sand.But it may be extremely difficult to measure directly the aerodynamic characteristics of the airflow near the real vegetation in field experiments on account of restriction by many objective factors.Therefore,numerous investigations have been carried out to study the efficiency of windbreaks by conducting wind tunnel experiments on simulated models or using computational fluid dynamics(CFD) simulation instead of field measurements.Plant models are simplified at some level to be used for numerical simulation in existing literatures.It is a little distortion of leaves in details if the tree canopy is regarded as a whole region which can have a certain influence on the CFD simulation.Hence,one modeling approach that combines Visual Basic for applications(VBA) and computer aided design(CAD) technology is proposed to design 3D virtual plant models.The tree models used for numerical simulation of wind flow around trees are more lifelike.In addition,this method can be applied for creating a 3D virtual vegetation library.It is also more convenient to get the diversified biological indicators by digital plants in computer. 展开更多
关键词 plant model virtual organ SKELETON wind flow numerical simulation
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Trait-based representation of hydrological functional properties of plants in weather and ecosystem models 被引量:2
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作者 Ashley M. Matheny Golnazalsadat Mirfenderesgi Gil Bohrer 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第1期1-12,共12页
Land surface models and dynamic global vegetation models typically represent vegetation through coarse plant functional type groupings based on leaf form, phenology, and bioclimatic limits. Although these groupings we... Land surface models and dynamic global vegetation models typically represent vegetation through coarse plant functional type groupings based on leaf form, phenology, and bioclimatic limits. Although these groupings were both feasible and functional for early model generations, in light of the pace at which our knowledge of functional ecology, ecosystem demographics, and vegetation-climate feedbacks has advanced and the ever growing demand for enhanced model performance, these groupings have become antiquated and are identified as a key source of model uncertainty. The newest wave of model development is centered on shifting the vegetation paradigm away from plant functional types(PFTs)and towards flexible trait-based representations. These models seek to improve errors in ecosystem fluxes that result from information loss due to over-aggregation of dissimilar species into the same functional class. We advocate the importance of the inclusion of plant hydraulic trait representation within the new paradigm through a framework of the whole-plant hydraulic strategy. Plant hydraulic strategy is known to play a critical role in the regulation of stomatal conductance and thus transpiration and latent heat flux. It is typical that coexisting plants employ opposing hydraulic strategies, and therefore have disparate patterns of water acquisition and use. Hydraulic traits are deterministic of drought resilience, response to disturbance, and other demographic processes. The addition of plant hydraulic properties in models may not only improve the simulation of carbon and water fluxes but also vegetation population distributions. 展开更多
关键词 Hydraulic traits Land-surface modeling Whole-plant hydraulic strategy Trait-based models Demographic models plant functional type
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Use of Linear Spectral Mixture Model to Estimate Rice Planted Area Based on MODIS Data 被引量:2
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作者 WANG Lei Satoshi UCHID 《Rice science》 SCIE 2008年第2期131-136,共6页
MODIS (Moderate Resolution Imaging Spectroradiometer) is a key instrument aboard the Terra (EOS AM) and Aqua (EOS PM) satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classi... MODIS (Moderate Resolution Imaging Spectroradiometer) is a key instrument aboard the Terra (EOS AM) and Aqua (EOS PM) satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale. 展开更多
关键词 RICE planted area Moderate Resolution Imaging Spectroradiometer Thematic Mapper data mixed pixel linear spectral mixture model
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