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Testing allometric scaling relationships in plant roots

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Forest Ecosystems 2020年第4期7卷 770-780页

作者： Qiang Deng Zhiyou Yuan Xinrong Shi T.Ryan Lock Robert L.Kallenbach State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100ShaanxiChina. University of Chinese Academy of Sciences Beijing 100049China. Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100ShaanxiChina Division of plant Sciences College of AgricultureFoodand Natural ResourcesUniversity of Missouri108 Waters HallColumbiaMO 65211USA.

Background:Metabolic scaling theory predicts that plant productivity and biomass are both ***,this theory has not yet been tested in plant ***:In this study,we tested how metabolic scaling occurs in plants using a comprehensive plant root dataset made up of 1016 observations from natural *** generated metabolic scaling exponents by logtransformation of root productivity versus ***:Results showed that the metabolic scaling exponents of fine root(roots(>2mm in diameter).Conclusions:We found isometric metabolic scaling in fine roots,a metabolically active organ similar to seedlings or *** findings also indicate a shift in metabolic scaling during plant ***,our study supports the absence of any unified single constant scaling exponent for metabolism-biomass relationships in terrestrial plants,especially for forests with woody species.

关键词： Allometry Biomass Metabolic scaling plant roots Productivity

Edge Detection of plant roots Image via Gabor Wavelet Theory

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Edge Detection of Plant Roots Image via Gabor Wavelet Theory

Effects of loading rate on root pullout performance of two plants in the eastern Loess Plateau,China

2011 Chinese Control and Decision Conference（CCDC）

作者： Wen-long Song is with the Department of Electromechanics Engineering,Northeast Forestry University,Harbin 150040,China. Li-hui Wang is with the Department of Electromechanics Engineering,Northeast Forestry University,Harbin 150040,China.Liang-kuan Zhu is with the Department of Electromechanics Engineering,Northeast Forestry University,Harbin 150040,China.Fa-yi Qu is with the Department of Electromechanics Engineering,Northeast Forestry University,Harbin 150040,China.

The pictures extracted from the plant roots often have quite big noises and often affected greatly by the light intensity,neither could we achieve satisfactory results by using the traditional image edge detection method to detect the edge *** this issue,a method for edge detection and its application in edge image detection for plant roots via gabor wavelet theory is proposed,which is able to filter from different directions and scales to determine the edge of the texture under perfect frequency,and proposes methods that using Gabor wavelet theory to detect the image edges of the plant *** results show that compared with other traditional edge detection methods,the proposed approach is effective in reduction of color space dimensionality and robust to noise.

关键词： plant roots Edge Detection Gabor wavelet theory Image Processing

来源： cnki会议评论

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cnki会议

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Journal of Arid Land 2023年第9期15卷 1129-1142页

作者： ZHANG Chaobo LI Rong JIANG Jing YANG Qihong College of Water Resources Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of the Regulation and Flood Control of Middle and Lower Reaches of the Changjiang River under Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan 430010China

Root pullout performance of plants is an important mechanical basis for soil reinforcement by plant roots in the semi-arid *** have shown that it is affected by plant factors(species,ages,root geometry,etc.)and soil factors(soil types,soil moisture,soil bulk densities,etc.).However,the effects of loading rates on root pullout performance are not well *** explore the mechanical interactions under different loading rates,we conducted pullout tests on Medicago sativa *** Hippophae rhamnoides *** under five loading rates,i.e.,5,50,100,150,and 200 mm/*** addition,tensile tests were conducted on the roots in diameters of 0.5-2.0 mm to compare the relationship between root tensile properties and root pullout *** showed that two root failure modes,slippage and breakage,were observed during root pullout *** *** roots were pulled out,while 72.2%of *** roots were *** maximum fracture diameter and fracture root length of *** were 1.22 mm and 7.44 cm under 100 mm/min loading rate,*** displacement values were 4.63%(±0.43%)and 8.91%(±0.52%)of the total root length for *** and ***,*** values of maximum pullout force were 14.6(±0.7)and 17.7(±1.8)N under 100 mm/min for *** and ***,*** of the maximum pullout strength for *** and *** were 38.38(±5.48)MPa under 150 mm/min and 12.47(±1.43)MPa under 100 mm/min,***-soil friction coefficient under 100 mm/min was significantly larger than those under other loading rates for both the two *** of the maximum root pullout energy for *** and *** were 87.83(±21.55)mm•N under 100 mm/min and 173.53(±38.53)mm•N under 200 mm/min,*** pullout force was significantly related to root diameter(P<0.01).Peak root pullout force was significantly affected by loading rates when the effect of root diameter was included(P<0.01),and vice *** fo

关键词： plant roots soil reinforcement loading rate root pullout properties root-soil interaction loess area

Evaluation of Cytogenetic Effects of Isoproturon on the Root Meristem Cells of Allium sativum

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Biomedical and Environmental Sciences 2001年第3期14卷 214-219页

作者： L. K. S. CHAUHAN, P. N. SAXENA, AND S. K. GUPTA1Cell Biology Section, Industrial Toxicology Research Centre, P. B. No. 80, M. G. Marg, Lucknow- 226001, India\ \ Industrial Toxicology Research Centre 印度 226001

Objective\ To validate the use of Allium sativum as a reliable test model for genotoxicity, isoproturon, a substituted phenylalkylurea herbicide, was evaluated on the root meristem cells by this plant system. Method\ Test concentrations were selected by determining EC50 and root tips were exposed to various concentrations for 6 or 24 hr. EC50 concentration was calculated to be 70.8 ppm for the root growth. In addition to root growth retardation exposure to isoproturon induced morpholoogical changes like discolouration and stiffness of roots. Results\ Exposure to various experimental concentrations of isoproturon (35-280 ppm), including EC50, significantly and dose-dependently inhibited the mitotic index and induced chromosome breaks/mitotic aberrations at 6 or 24 hr. Conclusion\ The frequency of aberrations was found to be decreased in a dose dependant manner at 24 or 48 hr post exposure, however in comparison of control cells the frequency of aberrations was considerably high which indicates genotoxicity potentials of isoproturon. Further, present study also suggests that Allium sativum is a sensitive, efficient, and reliable test system for measuring the genotoxicity potential of environmental chemicals.

关键词： Phenylurea Compounds Chromosome Aberrations DNA Damage Dose-Response Relationship, Drug Garlic Herbicides Lethal Dose 50 Methylurea Compounds Mitosis Mutagenicity Tests plant roots Sensitivity and Specificity

SIMPLIFIED ORDER CONDITIONS OF SOME CANONICAL DIFFERENCE SCHEMES

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Journal of Computational Mathematics 1995年第1期13卷 1-19页

作者： Zhu Wen-jie Qin Meng-zhao(State Key Laboratory of Scientific and Engineering Computing,Computing Center, Academia Sinica, Beijing, China ) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

The main purpose of this paper is to develop and simplify the general conditions for an s-stage explicit canonical difference scheme of q-th order, while the simplified order conditions for canonical RKN methods which... 详细信息

关键词： Vertices plant roots Product labeling Ordinary differential equations Sons Mathematical monotonicity Integration techniques

Effect of rhizosphere on soil microbial community and in-situ pyrene biodegradation

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Frontiers of Environmental Science & Engineering 2008年第4期2卷 468-474页

作者： Yuhong SU Xueyun YANG Cary T.CHIOU Chemistry Department Xinjiang UniversityUrumqi 830046China College of Resources and Environment Northwest A&F UniversityYangling 712100China U.S.Geological Survey Box 25046MS 408Denver Federal CenterDenverCO 80225USA

To access the influence of a vegetation on soil microorganisms toward organic pollutant biogegration,this study examined the rhizospheric effects of four plant species(sudan grass,white clover,alfalfa,and fescue)on the soil microbial community and in-situ pyrene(PYR)*** results indicated that the spiked PYR levels in soils decreased substantially compared to the control soil without *** equal planted densities,the efficiencies of PYR degradation in rhizosphere with sudan grass,white clover,alfalfa and fescue were 34.0%,28.4%,27.7%,and 9.9%,***,on the basis of equal root biomass the efficiencies were in order of white clover..*** increased PYR biodegradation was attributed to the enhanced bacterial population and activity induced by plant roots in the *** microbial species and biomasses were elucidated in terms of microbial phospholipid ester-linked fatty acid(PLFA)*** principal component analysis(PCA)revealed significant changes in PLFA pattern in planted and non-planted soils spiked with *** PLFAs in planted soils were all higher than those in non-planted *** assemblages indicated that bacteria were the primary PYR degrading microorganisms,and that Gram-positive bacteria exhibited higher tolerance to PYR than Gram-negative bacteria did.

关键词： pyrene rhizosphere plant roots microbial community microbial degradation phospholipid esterlinked fatty acid(PLFA)