scholarly journals Pollination systems and floral traits in cerrado woody species of the Upper Taquari region (central Brazil)

2006 ◽  
Vol 66 (2a) ◽  
pp. 543-552 ◽  
Author(s):  
F. Q. Martins ◽  
M. A. Batalha
Keyword(s):  
Principal Component Analysis ◽  
Plant Species ◽  
Principal Component ◽  
Woody Species ◽  
Floral Traits ◽  
Central Brazil ◽  
Large Dispersion ◽  
Functional Features ◽  
Pollination Systems ◽  
Plant Pollinator

Plant species present flowers with varied morphological and functional features, which may be associated to pollination systems, including species pollinated by wind, beetles, moths, bees, small insects, birds, or bats. We calculated the frequencies of the pollination systems among woody species in five cerrado fragments in central-western Brazil and tested whether the pollination systems were indeed related to floral traits. We sampled 2,280 individuals, belonging to 121 species, ninety-nine of which were described in relation to all floral traits. Most species had diurnal anthesis, pale colors, and open flowers. The most frequent groups were those composed by the species pollinated by bees, small insects, and moths. A Principal Component Analysis of the species and floral traits showed that there was a grouping among species with some pollination systems, such as those pollinated mainly by beetles, moths, birds, and bats, for which inferences based on the floral traits are recommended in cerrado sites. For the species pollinated mainly by bees or small insects, inferences based on the floral traits are not recommended, due to the large dispersion of the species scores and overlapping between these two groups, which probably occurred due to the specificity absence in plant-pollinator relationships.

scholarly journals Rhamnella brachycarpa (Rhamnaceae), a new species from Hainan Island, China

PhytoKeys ◽  
2019 ◽  
Vol 132 ◽  
pp. 19-29
Author(s):  
Zhiqiang Lu ◽  
Yongshuai Sun
Keyword(s):  
Principal Component Analysis ◽  
New Species ◽  
Principal Component ◽  
Woody Species ◽  
Hainan Island ◽  
Component Analysis ◽  
Morphological Characters ◽  
The Other ◽  
A New Species

Rhamnella brachycarpa Z. Qiang Lu & Y. Shuai Sun, a new evergreen woody species from Hainan Island, is described and illustrated. The specimens of this new species have previously been identified and placed under R. rubrinervis (H. Lév.) Rehder, with which it shares evergreen leaves, erect and climbing habits and axillary flowering branches with bracteole leaves. However, the specimens from three distinct Hainan populations significantly differ from those of R. rubrinervis from other regions with smaller length to width ratios of leaves, fruit and seeds, smaller sizes of fruit and seeds and mucronate seed apices. Principal Component Analysis of the closely related taxa, based on multiple morphological characters, further recognised two separated groups. One of them comprises R. tonkinensis and R. rubrinervis, the other merely includes all individuals from these distinct Hainan populations. Therefore, R. brachycarpa, based on these distinct Hainan populations, is here erected as a new species, distinctly different from its published relatives.

scholarly journals Spatiotemporal shifts in the role of floral traits in shaping tropical plant-pollinator interactions

2020 ◽  
Author(s):  
Yannick Klomberg ◽  
Robert Tropek ◽  
Jan E.J. Mertens ◽  
Ishmeal N. Kobe ◽  
Jiří Hodeček ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Elevational Gradient ◽  
Floral Traits ◽  
Pollination Syndrome ◽  
Floral Trait ◽  
Mount Cameroon ◽  
Tropical Plant ◽  
Random Forest Models ◽  
Pollination Systems ◽  
Plant Pollinator

AbstractThe pollination syndrome hypothesis predicts that plants pollinated by the same pollinator group bear convergent combinations of specific floral traits. Nevertheless, some studies have shown relatively low predictive power for these floral trait combinations. This discrepancy may be caused by changes in the importance of specific floral traits for shaping interactions under different environmental conditions and for different pollinator groups. To test this, we studied pollination systems and floral traits along an elevational gradient on Mount Cameroon during wet and dry seasons. Using Random Forest models, allowing the ranking of traits by significance, we demonstrated that some floral traits are more important than others in shaping interactions and that these traits predict pollinators relatively well. However, the distribution and importance of traits varies under different environmental conditions. Our results imply the need to improve our trait-based understanding of plant-pollinator interactions to better inform the debate surrounding pollination syndrome hypothesis.

scholarly journals Principal Component Analysis of Chlorophyll Content in Tobacco, Bean and Petunia Plants Exposed to Different Tropospheric Ozone Concentrations

2014 ◽  
Vol 12 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Klaudia Borowiak ◽  
Janina Zbierska ◽  
Anna Budka ◽  
Dariusz Kayzer
Keyword(s):  
Principal Component Analysis ◽  
Chlorophyll Content ◽  
Plant Species ◽  
Ozone Concentration ◽  
Tropospheric Ozone ◽  
Principal Component ◽  
Ambient Air ◽  
Component Analysis ◽  
Chlorophyll Contents ◽  
Ozone Concentrations

Abstract Three plant species were assessed in this study - ozone-sensitive and -resistant tobacco, ozone-sensitive petunia and bean. Plants were exposed to ambient air conditions for several weeks in two sites differing in tropospheric ozone concentrations in the growing season of 2009. Every week chlorophyll contents were analysed. Cumulative ozone effects on the chlorophyll content in relation to other meteorological parameters were evaluated using principal component analysis, while the relation between certain days of measurements of the plants were analysed using multivariate analysis of variance. Results revealed variability between plant species response. However, some similarities were noted. Positive relations of all chlorophyll forms to cumulative ozone concentration (AOT 40) were found for all the plant species that were examined. The chlorophyll b/a ratio revealed an opposite position to ozone concentration only in the ozone-resistant tobacco cultivar. In all the plant species the highest average chlorophyll content was noted after the 7th day of the experiment. Afterwards, the plants usually revealed various responses. Ozone-sensitive tobacco revealed decrease of chlorophyll content, and after few weeks of decline again an increase was observed. Probably, due to the accommodation for the stress factor. While during first three weeks relatively high levels of chlorophyll contents were noted in ozone-resistant tobacco. Petunia revealed a slow decrease of chlorophyll content and the lowest values at the end of the experiment. A comparison between the plant species revealed the highest level of chlorophyll contents in ozone-resistant tobacco.

scholarly journals Medicinal Plants in Semi-Natural Grasslands: Impact of Management

2021 ◽  
Author(s):  
Marika Kose ◽  
Indrek Melts ◽  
Atsushi Ohwaki ◽  
Kei Uchida ◽  
Katrin Heinsoo
Keyword(s):  
Principal Component Analysis ◽  
Medicinal Plants ◽  
Medicinal Plant ◽  
Plant Species ◽  
Principal Component ◽  
Medicinal Plant Species ◽  
Species List ◽  
Natural Grasslands ◽  
Wooded Meadows ◽  
The Impact

Abstract Background: Semi-natural grasslands as valuable ecosystems are significant for their high biodiversity, cultural importance and landscape values. Quantitative information about medicinal plants in semi-natural grasslands facilitates the evaluation of ecosystem services of these plant communities. Methods: Different literature sources and floristic inventory databases were used to assess the ratio and frequency of medicinal plant species in several Estonian grassland types and the impact of management on these values assessed both in Estonian and Japanese case studies. Lists of medicinal plant species according to different definition scenarios is included as Supplementary Material. Principal Component Analysis was applied for environmental preferences of medicinal plant species compared to other vascular plant species in the semi-natural grasslands.Results: The ratio of medicinal plant species in local total plant species list was the largest in alvars, followed by floodplain and wooded meadows. The average number of medicinal plant species per study plot in wooded meadows and alvars was about twice that found in naturally growing broadleaved forest (according to the most detailed MP species list 7.2, 7.8 and 4.3, respectively). Fertilization of Estonian wooded meadows had no significant impact on medicinal plant species ratio, but decreased the proportion of medicinal plant biomass in total yield. Estonian coastal meadows had a short list of medicinal plant species and the impact of management quality depended therefore on adopted definition scenario. In Japanese Miscanthus sinensis grassland case mowing or burning+mowing combination should be preferred to favor medicinal plant species number. Principal Component Analysis revealed that MP species are more drought-tolerant, common and anthropophyte than the rest of studied grassland species.Conclusions: Alternative usage of herbaceous plant species from semi-natural grasslands is a promising option to achieve sustainable development goals and increase public awareness. Further close cooperation of ecologists, economists and pharmacists is required to guarantee fair and sustainable trade of this ecosystem service in the future.

scholarly journals Identification of Tropical Plants Leaves Image Base on Principal Component Analysis

2020 ◽  
Vol 4 (1) ◽  
pp. 64-75
Author(s):  
Indra Laksmana ◽  
Hendra Hendra ◽  
Sri Aulia Novita ◽  
Fithra Herdian ◽  
Mohamad Riza Nurtam ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Plant Species ◽  
Mangifera Indica ◽  
Leaf Shape ◽  
Principal Component ◽  
Component Analysis ◽  
Persea Americana ◽  
Commission Error ◽  
Tropical Plants ◽  
Durio Zibethinus

Difference and variation of leaves shape is usually used as primary identifier of the plant species. But some plants may have a similar leaf shape and thus require another more accurate identifier. This study applied principal component analysis (PCA) methods for identifying tropical plant species from the shape of the leaves. This method simplified the observed variables by reducing the dimensions of the information that is stored as much as 75%, so it did not eliminate important information and can save the data processing time. There were 100 images of leaves taken from several sides of the leaf in JPEG format with which the shape of leaves were look similar, like citrus (Citrus aurantifolia), durian (Durio zibethinus), guava (Psidium guajava), mango (Mangifera indica), jackfruit (Artocarpus heterophyllus), avocado (Persea americana), rambutan (Nephelium lappaceum), sapodilla (Manilkara zapota), red betel (Piper crocatum) and soursop (Annona muricata). Identification of those 10 kind plant leaves produced 97% accuracy rate. Measurement systems were designed using the K-fold Cross Validation with k = 10, the results of experiments shown omission error occurs on the leaves of guava, jackfruit and red betel while twice commission error were found on the leaves sapodilla and once on citrus leaves.

Scanning x-ray fluorescence microscopy and principal component analysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1752-1753
Author(s):  
Brian Cross
Keyword(s):  
Principal Component Analysis ◽  
Fluorescence Microscopy ◽  
Spatial Resolution ◽  
High Speed ◽  
Image Acquisition ◽  
Principal Component ◽  
Fluorescence Microscope ◽  
Acquisition Rate ◽  
X Ray ◽  
Speed Up

A relatively new entry, in the field of microscopy, is the Scanning X-Ray Fluorescence Microscope (SXRFM). Using this type of instrument (e.g. Kevex Omicron X-ray Microprobe), one can obtain multiple elemental x-ray images, from the analysis of materials which show heterogeneity. The SXRFM obtains images by collimating an x-ray beam (e.g. 100 μm diameter), and then scanning the sample with a high-speed x-y stage. To speed up the image acquisition, data is acquired "on-the-fly" by slew-scanning the stage along the x-axis, like a TV or SEM scan. To reduce the overhead from "fly-back," the images can be acquired by bi-directional scanning of the x-axis. This results in very little overhead with the re-positioning of the sample stage. The image acquisition rate is dominated by the x-ray acquisition rate. Therefore, the total x-ray image acquisition rate, using the SXRFM, is very comparable to an SEM. Although the x-ray spatial resolution of the SXRFM is worse than an SEM (say 100 vs. 2 μm), there are several other advantages.

A German version of the Intermittent Claudication Questionnaire (ICQ): cultural adaptation and validation

VASA ◽  
2012 ◽  
Vol 41 (5) ◽  
pp. 333-342 ◽  
Author(s):  
Kirchberger ◽  
Finger ◽  
Müller-Bühl
Keyword(s):  
Principal Component Analysis ◽  
Intermittent Claudication ◽  
Completion Time ◽  
Short Form ◽  
Principal Component ◽  
Component Analysis ◽  
German Version ◽  
Average Completion Time ◽  
Sf 36 ◽  
Related Quality

Background: The Intermittent Claudication Questionnaire (ICQ) is a short questionnaire for the assessment of health-related quality of life (HRQOL) in patients with intermittent claudication (IC). The objective of this study was to translate the ICQ into German and to investigate the psychometric properties of the German ICQ version in patients with IC. Patients and methods: The original English version was translated using a forward-backward method. The resulting German version was reviewed by the author of the original version and an experienced clinician. Finally, it was tested for clarity with 5 German patients with IC. A sample of 81 patients were administered the German ICQ. The sample consisted of 58.0 % male patients with a median age of 71 years and a median IC duration of 36 months. Test of feasibility included completeness of questionnaires, completion time, and ratings of clarity, length and relevance. Reliability was assessed through a retest in 13 patients at 14 days, and analysis of Cronbach’s alpha for internal consistency. Construct validity was investigated using principal component analysis. Concurrent validity was assessed by correlating the ICQ scores with the Short Form 36 Health Survey (SF-36) as well as clinical measures. Results: The ICQ was completely filled in by 73 subjects (90.1 %) with an average completion time of 6.3 minutes. Cronbach’s alpha coefficient reached 0.75. Intra-class correlation for test-retest reliability was r = 0.88. Principal component analysis resulted in a 3 factor solution. The first factor explained 51.5 of the total variation and all items had loadings of at least 0.65 on it. The ICQ was significantly associated with the SF-36 and treadmill-walking distances whereas no association was found for resting ABPI. Conclusions: The German version of the ICQ demonstrated good feasibility, satisfactory reliability and good validity. Responsiveness should be investigated in further validation studies.

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