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A Study of Fructification Quantitative Characteristics of Spartina alterniflora Lossel in Mangroves 被引量:7
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作者 覃盈盈 梁士楚 《Agricultural Science & Technology》 CAS 2009年第1期101-104,共4页
[Objective] The countermeasure on the number of fructification of Spartina alterniflora in the period of sexual reproduction and the component of seed yielding construction was explored.[Method] The Spartina altemiflo... [Objective] The countermeasure on the number of fructification of Spartina alterniflora in the period of sexual reproduction and the component of seed yielding construction was explored.[Method] The Spartina altemiflora in Mangroves conservation zone located at Hepu of Guangxi being taken as experimental material, its morphological and quantitative characteristics, as well as the weight of 100 full seeds at maturity stage in three different growth conditions( clay, loam and sand) were studied. [ Results] The results showed that Spartina alterniflora had the best growth pattern in the loam. The morphological factors of fructification of S. altemiflora grown in sand were larger then in others. In the three growth conditions the order of quantitative characteristics of fructification of S. alterniflora was clay 〉 sand 〉 loam and the seeds in spikelet at top position were more maturity than those at the button position. [ Conclusion] In good condition, the Spartina altemiflora growth was vigor but the ratio of seed-setting was low. 展开更多
关键词 Spartina altemiflora Different habitat FRUCTIFICATION Quantitative characteristics
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Application of Statistic Analysis on the Selection of Quantitative Characteristics Listed in the DUS Test Guideline of Tagetes L. 被引量:1
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作者 刘艳芳 张建华 +6 位作者 杨晓洪 王江民 李彦刚 陈海荣 李向东 张惠 管俊娇 《Agricultural Science & Technology》 CAS 2012年第9期2021-2023,2033,共4页
[Objective] This paper researched how to use specific approach to select quantitative characteristics which would be listed in the DUS Test Guideline of Tagetes L. [Method] With the aid of statistic analysis, the unif... [Objective] This paper researched how to use specific approach to select quantitative characteristics which would be listed in the DUS Test Guideline of Tagetes L. [Method] With the aid of statistic analysis, the uniformity, stability and correlation of 14 pre-selected characteristics were analyzed. [Result] The expression of peduncle length of terminal flower had low uniformity within a variety; the expres- sion of main stem thickness was not stable in continuous growing cycles; there were four pairs of quantitative characteristics which are (very) significantly correlated, namely, leaf length and leaf width, diameter of flower head and length of outer ligu- late floret, number of ligulate floret whorls and number of ligulate floret, leaf width and width of terminal leaflet of pinnate leaves. Based on the requirements of char- acteristic selection and the results of statistic analysis, five characteristics including peduncle length of terminal flower, thickness of the main stem, leaf width, length of outer ligulate floret and number of ligulate floret were deleted. [Conclusion] For the first time, this paper introduced the application of statistic analysis on the selection of quantitative characteristics. 展开更多
关键词 DUS Test Guideline of Tagetes L. Quantitative characteristic Statisticanalysis
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Statistic Analysis on Quantitative Characteristics for Developing the DUS Test Guideline of Ranunculus asiaticus L. 被引量:2
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作者 LIU Yan-fang ZHANG Jian-hua +6 位作者 Lü Bo3 YANG Xiao-hong LI Yan-gang WANG Ye WANG Jiang-min ZHANG Hui GUAN Jun-jiao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第6期971-978,共8页
Selection of quantitative characteristics, division of their expression ranges, and selection of example varieties are key issues on developing DUS Test Guidelines, which are more crucial for quantitative characterist... Selection of quantitative characteristics, division of their expression ranges, and selection of example varieties are key issues on developing DUS Test Guidelines, which are more crucial for quantitative characteristics since their expressions vary in different degrees. Taking the development of DUS Test Guideline of Ranunculus asiaticus L. as an example, this paper applied statistic-based approaches for the analyses of quantitative characteristics. We selected 9 quantitative characteristics from 18 pre-selected characteristics, based on within-variety uniformity, stability between different growing cycles, and correlation among characteristics, by the analyses of coefficient of variation, paired-samples t-test and partial correlation. The expression ranges of the 9 selected quantitative characteristics were divided into different states using descriptive statistics and distribution frequency of varieties. Eight of the 9 selected quantitative characteristics were categorized as standard characteristics as they showed one peak in distribution frequency of 120 varieties in various expressions of the characteristics, whereas, plant height can be categorized as grouping characteristic since it gave two peaks, and can group the varieties into pot and cut varieties. Finally, box-plot was applied to visually select the example varieties, and varieties 7, 12, and 28 were determined as the example varieties for plant height. The methods described in this paper are effective for the selection of quantitative characteristics, division of expression ranges, and selection of example varieties in Ranunculus asiaticus L. for DUS test, and may also be interest for other plant genera. 展开更多
关键词 DUS Test Guideline quantitative characteristic statistic analysis expression range of characteristic example variety
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Quantitative Characteristics Analysis of FY4A Satellite Products during a Thunderstorm Weather Process
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作者 Ankun WU Man HOU Chi ZHANG 《Meteorological and Environmental Research》 CAS 2022年第6期49-54,59,共7页
Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm,the relationship between lightning activity and four satellite digital products:blackbody radiation brightness temperature(... Based on the lightning monitoring and FY4A satellite data in 12 periods during a thunderstorm,the relationship between lightning activity and four satellite digital products:blackbody radiation brightness temperature(TBB),cloud top temperature(CTT),cloud top height(CTH)and cloud top pressure(CTP)was quantitatively analyzed.The following conclusions were obtained:(1)at lightning location,90.5%of TBB values were less than 214.1 K;88.5%of CTT values were less than 207.7 K;88.5%of CTP values were less than 137.7 hPa,and 88.5%of CTH values were greater than 14872 m.At location without lightning,92.5%of TBB values were greater than 214.1 K;90.4%of CTT values were greater than 207.7 K;89%of CTP values were greater than 137.7 hPa,and 92%of CTH values were less than 14872 m.(2)Lightning activity was concentrated in the cloud area with TBB between 190-210 K,CTT between 185-210 K,CTP between 50-150 hPa and CTH between 12-18 km.Lightning intensity was roughly positively correlated with TBB,CTT and CTP,and negatively correlated with CTH.With the increase of CTH,lightning intensity decreased.(3)TBB,CTT,CTP and CTH can well indicate the location and activity frequency of lightning in thunderstorm weather. 展开更多
关键词 Lightning activity FY4A satellite products Quantitative characteristic analysis
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The dual choice of geodetic horizontal reference systems for Ukraine
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作者 Elena Novikova Alena Palamar Rostyslav Lopunov 《Geodesy and Geodynamics》 EI CSCD 2023年第3期254-264,共11页
Almost all European countries use at least two horizontal reference systems, which allow them to minimize all risks when changing the coordinate system. The first system is used for the needs of the national survey in... Almost all European countries use at least two horizontal reference systems, which allow them to minimize all risks when changing the coordinate system. The first system is used for the needs of the national survey in general, and also for technical applications in engineering surveys. A brief description of this system can be written by the formula: Geocentric Ellipsoid(GRS80) + Projection(UTM). More than half of the European countries for the second national systems use the GRS80 geocentric ellipsoid together with a projection other than UTM, some of them continue to use the projection of the old coordinate systems. The rest of the countries, excluding Ukraine, adapted the existing national coordinate systems to modern requirements, removing deformations from them concerning the ETRS89. A small number of European countries have implemented the GRS80 geocentric ellipsoid together with the UTM projection for cadastral surveys and topographic maps with a scale of 1:5000 and larger. Only one country, Ukraine, chose a variant for the new coordinate system(UCS2000), which is briefly written by the formula: Old Not Geocentric Ellipsoid + New Projection. The analysis of modern coordinate systems of Europe made it possible to formulate two variants of the future coordinate system of Ukraine based on a geocentric ellipsoid. It is shown that the transition to a geocentric ellipsoid will change the coordinates and heights of the points, but practically will not change the distance between the points and the area of the parcels. 展开更多
关键词 UTM GRS80 Projection parameters Quantitative characteristics of land parcels UCS2000
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Selection of Example Varieties Used in the DUS Test Guideline of Tagetes L. 被引量:1
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作者 刘艳芳 张建华 +6 位作者 王烨 陈海荣 徐云 杨晓洪 张惠 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第10期2110-2111,2116,共3页
[Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurement... [Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurements of flower diameter of 25 varieties were collected and then analyzed by using the box plot to illustrate the uniformity and stability of flower diameter of each variety.[Result] According to the information of variability,distribution symmetry of measurements and outliers of flower diameter of varieties provided by box plots,variety 16,2 and 4 were selected as the example varieties for the three expression states with respective flower diameter of 3.0-4.4,6.0-7.4 and 9.0-10.4 cm.[Conclusion] The box plot is an efficient method for the general analysis of varieties,which provides information covering the actual and possible expression range,median and outliers of measurements of flower diameter of each variety.It also provides references for selecting example varieties for other quantitative characteristics and evaluating the quality of varieties. 展开更多
关键词 DUS Test Guideline of Tagetes L. Quantitative characteristic Example variety The box plot
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Community Structure and Diversity of Ground Cover Plants in Tianjin Binhai International Airport 被引量:1
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作者 Xiaobo LIU Huanran XU +3 位作者 Hong YUAN Bin HE Shulan ZHAO Li'an DUO 《Agricultural Biotechnology》 CAS 2017年第3期30-33,70,共5页
By using quadrat sampling method, the community structure and diversity of ground cover plants in the flight area in Tianjin Binhai International Airport were investigated from spring to autumn in 2015. The results sh... By using quadrat sampling method, the community structure and diversity of ground cover plants in the flight area in Tianjin Binhai International Airport were investigated from spring to autumn in 2015. The results showed that 58 plant species were recorded at the airport, belonging to 18 families and 48 genera. Dominant plant species showed seasonal characteristics. Specifically, lxeri chinensis ( Thunb. ) Nakai and Lagopsis supina ( Steph. ) Ik. -Gal. ex Knorr. were the dominant species in spring; Lagopsis supina, Cirsium setosum (Willd.) MB, Plantago asiatica L. , Cynanchum chinense R. Br. and Humulus scandens (I_our.) Merr. were the dominant species in summer; Chloris virgata Sw. and Eleusine indica (L.) Gaertn. were the dominant species in autumn. Quantitative characteris- tics of the dominant species, including the density, frequency, coverage and height, varied in different seasons. In different seasons, changes in the diversity of plant communities in three sampling points were analyzed. The results indicated that plant communities in summer exhibited the highest diversity and the most uni- form distribution. This study provided a theoretical basis for avoidance of bird strike in Tianjin Binhai International Airport. 展开更多
关键词 Tianjin Binhai International Airport Plant community structure Quantitative characteristics Plant diversity
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Impacts of precipitation variation and soil and water conservation measures on runoff and sediment yield in the Loess Plateau Gully Region, China 被引量:8
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作者 XIA Lu SONG Xiao-yu +3 位作者 FU Na MENG Chun-fang LI Huai-you LI Yao-lin 《Journal of Mountain Science》 SCIE CSCD 2017年第10期2028-2041,共14页
The Loess Plateau of China has experienced a lengthy drought and severe soil erosion.Changes in precipitation and land use largely determine the dynamics of runoff and sediment yield in this region. Trend and mutation... The Loess Plateau of China has experienced a lengthy drought and severe soil erosion.Changes in precipitation and land use largely determine the dynamics of runoff and sediment yield in this region. Trend and mutation analyses were performed on hydrological data(1981–2012) from the Yanwachuan watershed in the Loess Plateau Gully Region to study the evolution characteristics of runoff and sediment yield. A time-series contrasting method also was used to evaluate the effects of precipitation and soil and water conservation(SWC) on runoff and sediment yield. Annual sediment yield declined markedly from 1981 to 2012 although there was no significant change in annual precipitation and annual runoff. Change points of annual runoff and annual sediment yield occurred in 1996 and 1997,respectively. Compared with that in the baseline period(1981–1996), annual runoff and annual sediment yield in the change period(1997–2012)decreased by 17.0% and 76.0%, respectively, but annual precipitation increased by 6.3%. Runoff decreased in the flood season and normal season, but increased in the dry season, while sediment yield significantly declined in the whole study period. The SWC measures contributed significantly to the reduction of annual runoff(137.9%) and annual sediment yield(135%) and were more important than precipitation. Biological measures(forestland and grassland) accounted for 61.04% of total runoff reduction, while engineering measures(terraces and dams) accounted for 102.84% of total sediment yield reduction. Furthermore, SWC measures had positive ecological effects. This study provides a scientific basis for soil erosion control on the Loess Plateau. 展开更多
关键词 Quantitative impact Trend analysis Evolution characteristics Runoff and sediment yield Rainfall Land use change
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Quantitative Analysis on Distribution of Modifier in Microstructure of SBS Modifi ed Asphalt 被引量:1
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作者 殷巍 杨群 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期740-744,共5页
A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the prepar... A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the preparation of modified asphalt. By sampling specimens from the top, middle, and bottom, a number of microscope slides were made and 400 times micro images were gained. Binarized with the software of MATLAB, the images then went to the process of distribution test, when four typical distributions were employed to investigate the distribution of modifi er spread in asphalt. The distribution characteristic and its parameter were both found. The results show that asphalt phase clearly obeys Poisson distribution, and its parameter, λ, is bond up with the condition SBS performs in. Based on this parameter, indexes can be set up to evaluate the structure of the mixture and its performance as well. Compared with that modifi ed with mixed SBS, the asphalt modifi ed with branched SBS has better performance but worse stability, for it is easier to segregate. 展开更多
关键词 SBS modifi ed asphalt microstructure quantitative index distribution characteristic
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Phenotypic Plasticity of Life History Characteristics: Quantitative Analysis of Delayed Reproduction of Green Foxtail (Setaria viridis) in the Songnen Plain of China 被引量:2
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作者 Hai-Yan Li Yun-Fei Yang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第6期641-647,共7页
Green foxtail (Setaria viridis L.) is a common weed species in temperate regions. Research on the effect of delayed reproduction on the phenotypic plasticity and regularity of the vegetative and reproductive growth ... Green foxtail (Setaria viridis L.) is a common weed species in temperate regions. Research on the effect of delayed reproduction on the phenotypic plasticity and regularity of the vegetative and reproductive growth is of vital significance for understanding population regulation and control of the weed in the growing season. Green foxtail seeds were sown every 10 days from 25 June to 24 August of 2004. The growth and production metrics were measured via harvesting tufts and statistical analysis was carried out. The results showed that the reproductive tillers, seed number, seed biomass and one thousand-seed weight of plants at the first sowing (25 June) approximately increased 28.8, 7 827.0, 1 104,0 and 12.3 times compared with that at the last sowing (24 August), respectively. Total tillers, reproductive tillers and height increased linearly as the reproductive period delayed, however, biomass increased exponentially. Quadratic equations best explained the relationships between the delayed reproductive period and seed number, inflorescence length, one thousand-seed weight, seed biomass. Based on the quantity and quality of seed production, weeding young seedlings emerging before July can be the most effective weed-control strategy in the Songnen Plain. 展开更多
关键词 delayed reproduction life history phenotypic plasticity quantitative characteristics Setaria viridis weed control
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Quantitative analysis of cerebrovascular characteristics of Parkinson's disease treated with acupuncture based on magnetic resonance angiography 被引量:2
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作者 Yuan Yang Le He +3 位作者 Suhua Miao Rongsong Zhou Yuqi Zhang Yu Ma 《Brain Science Advances》 2021年第2期141-154,共14页
Background:Acupuncture has become an important alternative clinical treatment for Parkinson’s disease(PD),but its efficacy and the underlying mechanisms remain debatable.Using a newly developed magnetic resonance ang... Background:Acupuncture has become an important alternative clinical treatment for Parkinson’s disease(PD),but its efficacy and the underlying mechanisms remain debatable.Using a newly developed magnetic resonance angiography(MRA)method that has higher sensitivity for smaller and distal vessels and a novel tool that can trace vessels and extract vascular features,the immediate effects of acupuncture on intracranial vessels and blood flow in patients with PD as well as correlations with clinical outcomes were quantitatively evaluated.Methods:Fifteen PD patients received acupuncture at the Dazhui and Fengchi acupoint positions.MRA was performed before and after 30 min of treatment.The cerebral blood flow(CBF)and the length,volume,diameter,and signal intensity of the intracranial internal carotid artery(ICA)and middle cerebral artery(MCA)were measured.The Unified Parkinson’s Disease Rating Scale partⅢ(UPDRS-Ⅲ)and Visual Analogue Scale(VAS)were used to evaluate the motor symptoms and the subjective feelings of discomfort.Results:Acupuncture significantly reduced UPDRS-Ⅲand VAS scores.No significant changes were noted in the overall CBF before and after treatment.However,there was a significant extension effect on the length of the intracranial ICA and MCA and the distal MCA,and a significant increase in the number of branches of the MCA was found.Although acupuncture tended to increase the total volume of the intracranial ICA and the volume of the MCA,no statistical significance was reached.The total intensity was not altered,but the intensity and diameter of the M1 segment were significantly increased,whereas the intensity of the MCA was decreased.A positive correlation between M1 intensity changes and UPDRS-Ⅲchanges was found.Conclusions:Angiographic evaluation suggested that acupuncture had a significant effect on intracranial blood vessels,which is one possible mechanism for acupuncture improving the motor symptoms of PD. 展开更多
关键词 ACUPUNCTURE Parkinson’s disease magnetic resonance angiography quantitative cerebrovascular characteristics cerebral blood flow
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