Articoli di riviste: "Plant species composition"

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Markert, B., e R. Jayasekera. "Elemental composition of different plant species". Journal of Plant Nutrition 10, n. 7 (maggio 1987): 783–94. http://dx.doi.org/10.1080/01904168709363609.

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Luna, Belén, Beatriz Pérez, Alberto Cruz, Federico Fernández-González e José Manuel Moreno. "Fire homogeneizes plant species traits composition". Forest Ecology and Management 234 (novembre 2006): S199. http://dx.doi.org/10.1016/j.foreco.2006.08.318.

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Cochran, Alyssa T., Jemma Bauer, Jessica L. Metcalf, Petra Lovecka, Martina Sura de Jong, Sven Warris, Paul J. W. Mooijman, Ingrid van der Meer, Rob Knight e Elizabeth A. H. Pilon-Smits. "Plant Selenium Hyperaccumulation Affects Rhizosphere: Enhanced Species Richness and Altered Species Composition". Phytobiomes Journal 2, n. 2 (gennaio 2018): 82–91. http://dx.doi.org/10.1094/pbiomes-12-17-0051-r.

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Little is known about the microbiomes associated with plants with unusual properties, including plants that hyperaccumulate toxic elements such as selenium (Se). Se hyperaccumulators contain up to 1.5% of their dry weight in Se, concentrations shown to affect ecological interactions with herbivores, fungal pathogens and neighboring plants. Hyperaccumulators also enrich their surrounding soil with Se, which may alter the rhizobiome. To investigate whether plant Se affects rhizobacterial diversity and composition, we used a combination of culture-independent and culture-based approaches. Sequencing of 16S rRNA gene amplicons using the Illumina platform revealed that the rhizosphere microbiomes of Se hyperaccumulators were significantly different from nonaccumulators from the same site, with a higher average relative abundance of Pedobacter and Deviosa. Additionally, hyperaccumulators harbored a higher rhizobacterial species richness when compared with nonaccumulators from the same family on the same site. Independent from Se present at the site or in the host plant, the bacterial isolates were extremely resistant to selenate and selenite (up to 200 mM) and could reduce selenite to elemental Se. In conclusion, Se hyperaccumulation does not appear to negatively affect rhizobacterial diversity, and may select for certain taxa in the rhizosphere microbiome. Additionally, Se resistance in hyperaccumulator-associated bacteria and archaea may be widespread and not under selection by the host plant.

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Hoeksema, Jason D. "Plant–plant interactions vary with different mycorrhizal fungus species". Biology Letters 1, n. 4 (31 agosto 2005): 439–42. http://dx.doi.org/10.1098/rsbl.2005.0381.

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Because different species of mycorrhizal fungi have different effects on the growth of particular plant species, variation in mycorrhizal fungus species composition could cause changes in the strength of plant–plant interactions. Results are presented from a growth chamber experiment that compared the strength of interactions among seedlings of ponderosa pine ( Pinus ponderosa ) when the pines were colonized by two different groups of ectomycorrhizal fungi in the genus Rhizopogon . Plant density effects differed between the two groups of mycorrhizal fungi: plant growth was low regardless of density when plants were colonized with pine-specific Rhizopogon species, while plant growth declined with plant density when plants were colonized by Rhizopogon species having a broader host range. This result parallels results from previous studies showing that plant interactions are more antagonistic with mycorrhizal fungi than without, implying that plant responsiveness to beneficial mycorrhizal fungi declines with increasing plant density. If such effects are prevalent in plant communities, then variation in mycorrhizal fungus community composition is predicted to have a density-dependent effect on plants.

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Javad Eshaghi, Rad, Valadi Gelare, Salehzadeh Osman e Maroofi Hosein. "Effects of anthropogenic disturbance on plant composition, plant diversity and soil properties in oak forests, Iran". Journal of Forest Science 64, No. 8 (10 settembre 2018): 358–70. http://dx.doi.org/10.17221/13/2018-jfs.

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Three sites including “less disturbed”, “moderately disturbed” and “severely disturbed” were selected in Zagros forests in Kurdistan province (Iran). Three forest stands with similar physiographic conditions of each site were selected and three 400 m2 plots were assessed in each stand to record the floristic information and soil sample (0–30 cm). Different diversity indices were calculated for each sample. Cluster analysis and to collect soil samples detrended correspondence analysis were applied to categorize and investigate the vegetation trend. Indicator species analysis was used to determine the characteristic species. Tukey test was used to compare the variables amongst sites. The results showed that 47, 25, 15 species were exclusively observed in less disturbed, moderately disturbed and severely disturbed sites, respectively. Furthermore, cluster analysis illustrated the distinction amongst sites and detrended correspondence analysis result showed that the vegetation of the regions was ordinated by disturbance gradient. 21, 5, 7 characteristic species were respectively indicated in less disturbed, moderately disturbed and severely disturbed sites. In general, plant composition, plant diversity and soil quality were decreased dramatically along the disturbance gradient.

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Duffková, R., e H. Libichová. "Effects of cattle slurry application on plant species composition of moderately moist Arrhenatherion grassland". Plant, Soil and Environment 59, No. 11 (7 novembre 2013): 485–91. http://dx.doi.org/10.17221/62/2013-pse.

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Cattle slurry is frequently used fertilizer on grasslands, but little is known about its effect on plant species composition. The aim of this study was therefore to assess effect of different application rates of cattle slurry (S0 – 0, S1 – 60, S2 – 120, S3 – 180, S4 – 240 kg N/ha/year) on the plant species composition of three-cut grassland. The study was performed over 6 years on moderately moist upland Arrhenatherion grassland in the Czech Republic dominated by Alopecurus pratensis, Trisetum flavescens, and Poa spp. Species composition recorded in treatments with application of cattle slurry in rate up to 120 kg N/ha/year was similar to the unfertilized control. During first three years, species richness was similar in all treatments and then decreased the most in S4 followed by S3 treatment. Cover of short forbs increased in S0 and decreased with an increase in slurry application rate which supported tall grasses. Application of cattle slurry up to 120 kg N/ha/year can be considered as suitable compromise between maintenance of species rich grasslands and requirements of farmers for sufficient forage production.

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Montesinos-Tubée, Daniel B., Karle V. Sýkora, Víctor Quipuscoa-Silvestre e Antoine M. Cleef. "Species composition and phytosociology of xerophytic plant communities after extreme rainfall in South Peru". Phytocoenologia 45, n. 3 (1 novembre 2015): 203–50. http://dx.doi.org/10.1127/phyto/2015/0023.

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Urbina, Ifigenia, Jordi Sardans, Oriol Grau, Carl Beierkuhnlein, Anke Jentsch, Jüergen Kreyling e Josep Peñuelas. "Plant community composition affects the species biogeochemical niche". Ecosphere 8, n. 5 (maggio 2017): e01801. http://dx.doi.org/10.1002/ecs2.1801.

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Korul’kina, L. M., G. E. Zhusupova, E. E. Shul’ts e K. B. Erzhanov. "Fatty-acid composition of two Limonium plant species". Chemistry of Natural Compounds 40, n. 5 (settembre 2004): 417–19. http://dx.doi.org/10.1007/s10600-005-0002-5.

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Posatska, Nataliya M., Оxana А. Struk, Andrii R. Grytsyk, Tetiana H. Stasiv e Anatolii O. Klymenko. "Research of element composition of Verbena species". Pharmacia 68, n. 1 (12 febbraio 2021): 227–33. http://dx.doi.org/10.3897/pharmacia.68.e46513.

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Violation of homeostasis is often connected with a deficiency or excess of certain elements. Undeniable value of biologically active substances of plants is that they are contained in plant raw material in natural balanced complexes and they are an important source of macro- and microelements for a human organism. Study of a chemical composition, including macro- and microelements, a pharmacological effect of Verbena species is a basis for conduction of further researches. There are 250 species of Verbena genus, 3 of which, namely Verbena officinalis L., Verbena supina L. and Verbena hybrida Hort are growing in Ukraine. The aim of our research was to study macro- and microelements in the raw material of Verbena genus species, to reveal the influence of the conditions of growing on the content of elements in the Verbena officinalis L. herb, to compare element composition of the Verbena officinalis L. herb and herbal extracts. Macro- and microelement composition of raw material was researched by using the method of atom-emission spectrometry with inductively bounded plasma iCAP 7000 Duo. To determine the influence of the conditions of increase of macro- and microelements in Verbena officinalis L. herb, their quantity in soils and plants from different areas of growing was defined. To reveal the intensity of absorption of macro- and microelements from the soil by the plants, the coefficients of their biological accumulation were calculated. The comparative determination of the element composition of Verbena officinalis L. herb and herbal extracts VOH-0 (extractant – purified water) and VOH-7 (extractant – 70% ethanol) was also carried out to determine the degree of elements transfer from plant raw material into extracts. Results of the research show that in the samples of Verbena officinalis L. herb, Verbena hybrida Hort. herb and Verbena supine L. leaves there are 22 inorganic elements. Results of studying of element composition of Verbena officinalis L. herb and samples of soil from different areas of growing in Ivano-Frankivsk and Ternopil regions show that the quantitative and qualitative compositions of microelements depend on element exchange of these plants, conditions of growing and element composition of soil. The reverse dependence between the content of most elements in the soil and the coefficient of their accumulation in plants was found out. Concentration of elements in the herb and extracts was identified to have the same profile, but the quantitative content of elements was different, which was influenced by the extractor (purified water, 70% ethanol). Results of our research are currently relevant; they should be taken into account in the development of new herbal medicines, which would have desirable pharmacological effect in the future.

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WULANDARI, INDRI, RANDI HENDRAWAN, TEGUH HUSODO e ERRI N. MEGANTARA. "Vegetation structure and composition in Ciletuh Geopark, Sukabumi, Indonesia". Asian Journal of Forestry 2, n. 2 (1 dicembre 2018): 54–61. http://dx.doi.org/10.13057/asianjfor/r020203.

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Wulandari I, Hendrawan R, Husodo T, Megantara EN. 2018. Vegetation structure and composition in Ciletuh Geopark, Sukabumi, Indonesia. Asian J For 2: 54-61. Ciletuh Geopark has unique geological exposures and plant diversity that need to be maintained and managed to provide benefits, both to the environment and society. In order to manage plant diversity, the plant species that make up the area need to be identified. This research was conducted to determine the community structure and plants diversity of the Ciletuh Geopark. The results of the study were used as basic data in determining the pattern of biodiversity management in Ciletuh Geopark. The method used is a qualitative method, through an inventory of plant species and illustrating the vegetation profile diagram. Vegetation profile diagrams represent a vertical structure of the vegetation community. Data analysis was carried out qualitatively by describing vegetation conditions. Ciletuh Geopark has four types of communities, namely natural forests, horticultural gardens (gardens, humas, and fields), kebon tatangkalan (talun), coastal vegetation and mangroves. Ciletuh Geopark has 179 plant species, from understorey to trees. In this location, there has been a change in species diversity, which is dominated by crop plant species. However, based on its conservation status, there were also plants protected by the Indonesian government, namely Rafflesia patma.

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Johnson, David, Gareth K. Phoenix e J. Philip Grime. "Plant community composition, not diversity, regulates soil respiration in grasslands". Biology Letters 4, n. 4 (15 aprile 2008): 345–48. http://dx.doi.org/10.1098/rsbl.2008.0121.

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Soil respiration is responsible for recycling considerable quantities of carbon from terrestrial ecosystems to the atmosphere. There is a growing body of evidence that suggests that the richness of plants in a community can have significant impacts on ecosystem functioning, but the specific influences of plant species richness (SR), plant functional-type richness and plant community composition on soil respiration rates are unknown. Here we use 10-year-old model plant communities, comprising mature plants transplanted into natural non-sterile soil, to determine how the diversity and composition of plant communities influence soil respiration rates. Our analysis revealed that soil respiration was driven by plant community composition and that there was no significant effect of biodiversity at the three levels tested (SR, functional group and species per functional group). Above-ground plant biomass and root density were included in the analysis as covariates and found to have no effect on soil respiration. This finding is important, because it suggests that loss of particular species will have the greatest impact on soil respiration, rather than changes in biodiversity per se .

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Belachew, Kifle, e Taye Tessema. "Assessment of Weed Flora Composition in Parthenium (Parthenium hysterophorus L.) Infested Area of East Shewa Zone, Ethiopia". Malaysian Journal of Medical and Biological Research 2, n. 2 (31 dicembre 2015): 105–12. http://dx.doi.org/10.18034/mjmbr.v2i2.397.

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Field survey on parthenium was conducted at East shewa Zone of Oromiya Regional State, Ethiopia during 2008 cropping season. The objectives of the study was to assess the weed flora composition and plant species that are growing in copetation with parthenium to use those plants as potential biological management options under field condition. Assessment of weed flora composition was carried out in five Kebeles (Farmers Association) of Boset District East Shewa Zone of Oromiya Regional State, Ethiopia. Data on the species composition were recorded and samples of weed flora compositions were collected. The result showed a total of eighty five different herbaceous plant species that were collected and recorded in 63 genera and 24 families. Poaceae (21), Asteraceae (11), Fabaceae (7) and Convolvulaceae (7) were by far the richest taxa and accounted together (55 %) of the entire flora of the study area. The major plant species having higher dominance value were Parthenium hysterophorus (25.6), Cassia tora (6.07), Argemone mexicana (5.83), Xanthium strumarium (4.53), Digitaria abyssinica (3.02) and Cyperus rotundus (2.86). Similarity index values of the species composition among different kebeles ranged from 65% to 78% which indicating that weed species compositions in these locations were similar. The diversity and evenness of species declined with increasing spread of parthenium which suggests negative influence that parthenium had on the status of species diversity in the studied area. In conclusion the selected plant species that were found competitive with parthenium based on their abundance and dominance values were Argemone mexicana, Cassia tora, and Xanthium strumarium which were suggested for detailed competition experiment in order to determine their competitiveness with P. hysterophorus and will be used for biological management of it.

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Chen, W., J. M. Scott, G. J. Blair e R. D. B. Lefroy. "Using plant cuticular alkanes to study plant-animal interactions on pastures". Canadian Journal of Animal Science 79, n. 4 (1 dicembre 1999): 553–56. http://dx.doi.org/10.4141/a99-046.

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Two experiments were conducted to validate an approach of using plant cuticular alkanes to estimate diet composition and fecal output. In the first experiment, n-alkane patterns of the four major pasture species were determined and compared and a further two sets of pasture mixtures were prepared to validate the use of plant n-alkane patterns to estimate species composition. In the second experiment, estimates of daily fecal output of grazing sheep were compared using controlled-released devices containing either Cr2O3 or alkanes. There were considerable differences in odd-numbered alkanes and in their total content between species. Results from the first experiment, where two sets of pasture mixtures were analyzed suggest that it is feasible to separate species composition using differences in n-alkane pattern. The second experiment showed that accurate estimation of daily fecal output can also be obtained using capsules containing alkanes. Key words: n-alkane, pasture, diet composition, fecal output

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Bremer, Christina, Gesche Braker, Diethart Matthies, Andreas Reuter, Christof Engels e Ralf Conrad. "Impact of Plant Functional Group, Plant Species, and Sampling Time on the Composition of nirK-Type Denitrifier Communities in Soil". Applied and Environmental Microbiology 73, n. 21 (31 agosto 2007): 6876–84. http://dx.doi.org/10.1128/aem.01536-07.

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ABSTRACT We studied the influence of eight nonleguminous grassland plant species belonging to two functional groups (grasses and forbs) on the composition of soil denitrifier communities in experimental microcosms over two consecutive years. Denitrifier community composition was analyzed by terminal restriction fragment length polymorphism (T-RFLP) of PCR-amplified nirK gene fragments coding for the copper-containing nitrite reductase. The impact of experimental factors (plant functional group, plant species, sampling time, and interactions between them) on the structure of soil denitrifier communities (i.e., T-RFLP patterns) was analyzed by canonical correspondence analysis. While the functional group of a plant did not affect nirK-type denitrifier communities, plant species identity did influence their composition. This effect changed with sampling time, indicating community changes due to seasonal conditions and a development of the plants in the microcosms. Differences in total soil nitrogen and carbon, soil pH, and root biomass were observed at the end of the experiment. However, statistical analysis revealed that the plants affected the nirK-type denitrifier community composition directly, e.g., through root exudates. Assignment of abundant T-RFs to cloned nirK sequences from the soil and subsequent phylogenetic analysis indicated a dominance of yet-unknown nirK genotypes and of genes related to nirK from denitrifiers of the order Rhizobiales. In conclusion, individual species of nonleguminous plants directly influenced the composition of denitrifier communities in soil, but environmental conditions had additional significant effects.

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McKibben, Michael, e Jeremiah A. Henning. "Hemiparasitic plants increase alpine plant richness and evenness but reduce arbuscular mycorrhizal fungal colonization in dominant plant species". PeerJ 6 (7 novembre 2018): e5682. http://dx.doi.org/10.7717/peerj.5682.

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Hemiparasitic plants increase plant biodiversity by reducing the abundance of dominant plant species, allowing for the establishment of subordinate species. Hemiparasites reduce host resources by directly removing nutrients from hosts, competing for light and space, and may indirectly reduce host resources by disrupting plant associations with symbiotic root fungi, like arbuscular mycorrhizal fungi and dark-septate endophytes. Here, we explored how a generalist hemiparasite, Castilleja, influences plant richness, evenness, community composition, and mycorrhizal colonization patterns across a ∼1,000 m elevational gradient in the North American Rocky Mountains. We hypothesized that the presence of Castilleja would be associated with increased plant richness and evenness, shaping plant community composition, and would reduce mycorrhizal colonization within dominant plant taxa. However, the magnitude of the effects would be contingent upon climate contexts, that is, elevation. Overall, we found that the presence of Castilleja was associated with an 11% increase in plant richness and a 5% increase in plant evenness, regardless of elevation. However, we found that the presence of Castilleja influenced plant composition at only two of the five sites and at the remaining three of five sites, plot pairing was the only predictor that influenced composition. Additionally, we found that the presence of Castilleja reduced mycorrhizal fungal colonization within dominant plant species by ∼20%, regardless of elevation. Taken together, our results suggest that hemiparasites regulate plant diversity, evenness, and interactions with mycorrhizal fungi independent of abiotic and biotic contexts occurring at the site, although overall effect on community composition is likely driven by site-level factors.

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Gjeta, Ermelinda, Jonathan Titus e Priscilla Titus. "Plant species occupy different habitats on the fortress walls in Elbasan, Albania". Hacquetia 20, n. 1 (1 marzo 2021): 81–90. http://dx.doi.org/10.2478/hacq-2020-0016.

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Abstract Vegetated walls are an important habitat for urban biodiversity. We conducted an analysis of the plant species that grow on the Elbasan, Albania fortress walls. Walls vary in age from 4th to 21st century, and in composition. On 71 walls we assessed 2787 plants of 35 species and recorded plant size, presence of flowers or fruits, height from the ground, crevice depth, wall aspect, wall age and composition, and distance to nearest opposing wall. Eleven species, two of which were ferns, composed 93.8% of the plants. The vast majority of plants flowered and fruited on the walls. Plant density ranged from 0.1–70 plants/m2. Species distributions varied significantly based on height on the wall, crevice depth, aspect and distance to the opposing wall. These differences may be influenced by dispersal mechanisms, moisture, substrate composition, and other important environmental factors. For example, Antirrhinum majus was generally found high on south facing walls in deep cracks whereas Umbilicus rupestris was found lower on north facing walls in shallower cracks. It is important that older walls colonized by plants be maintained such that a native flora can persist where natural rocky features are lacking.

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Aguirre-Jaimes, Armando, Juan Carlos López-Acosta e Rodolfo Dirzo. "Tropical rainforest fragmentation affects plant species richness, composition and abundance depending on plant-size class and life history". Botanical Sciences 99, n. 1 (27 ottobre 2020): 92–103. http://dx.doi.org/10.17129/botsci.2679.

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Background: Tropical rain forests have been impacted by land use change, leading to major deforestation and fragmentation. Understanding how fragmentation impacts plant communities is central for tropical conservation. Questions: i) How does species richness vary across a range of fragment sizes, and does it vary with plant size-structure? ii) how are species composition and floristic similarity affected by forest fragmentation? iii) does habitat fragmentation affect the representation of species with different life-history and regeneration patterns? Studied species: We sampled overall plant communities and calculated diversity metrics of mature-forest and light-demanding species, considering plants of different size-categories (defined by diameter at breast height, DBH). Study site: This study was carried out at Los Tuxtlas, Veracruz, Mexico. An area originally dominated extensive evergreen tropical forest, but currently highly fragmented Methods: We sampled plants in five forest fragments representing (2 - 36 ha), and a large patch of continuous forest (700 ha). Within each site we established ten-50 × 2 m transects and registered all woody plants with DBH > 1 cm. Results: Species richness declined as fragment size became smaller. Such decline was significant considering all plants (DBH > 1.0 cm) but became non-significant as plant size-category increased (DBH > 2.5, or > 10 cm.). Small fragments had distinguishable assemblages compared to continuous forest and also a reduction in the representation of mature-forest species compared to light-demanding species. Conclusions: Our findings confirm that fragmentation affects tropical plant species diversity, but the effect is differential, depending on plant size-category and life history.

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Schaffers, André P., Ivo P. Raemakers, Karlè V. Sýkora e Cajo J. F. ter Braak. "ARTHROPOD ASSEMBLAGES ARE BEST PREDICTED BY PLANT SPECIES COMPOSITION". Ecology 89, n. 3 (marzo 2008): 782–94. http://dx.doi.org/10.1890/07-0361.1.

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Adler, Paul R., Matt A. Sanderson, Paul J. Weimer e Kenneth P. Vogel. "Plant species composition and biofuel yields of conservation grasslands". Ecological Applications 19, n. 8 (dicembre 2009): 2202–9. http://dx.doi.org/10.1890/07-2094.1.

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Tabacchi, Eric, e Anne-Marie Planty Tabacchi. "FUNCTIONAL SIGNIFICANCE OF SPECIES COMPOSITION IN RIPARIAN PLANT COMMUNITIES". Journal of the American Water Resources Association 37, n. 6 (dicembre 2001): 1629–37. http://dx.doi.org/10.1111/j.1752-1688.2001.tb03665.x.

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Szymańska, Renata, e Jerzy Kruk. "Tocopherol content and isomers' composition in selected plant species". Plant Physiology and Biochemistry 46, n. 1 (gennaio 2008): 29–33. http://dx.doi.org/10.1016/j.plaphy.2007.10.009.

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Merriam, Kyle E., Scott H. Markwith e Michelle Coppoletta. "Livestock exclusion alters plant species composition in fen meadows". Applied Vegetation Science 21, n. 1 (19 settembre 2017): 3–11. http://dx.doi.org/10.1111/avsc.12333.

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Everson, T. M., G. P. Y. Clarke e C. S. Everson. "Precision in monitoring plant species composition in montane grasslands". Vegetatio 88, n. 2 (agosto 1990): 135–41. http://dx.doi.org/10.1007/bf00044830.

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Shahriary, E., M. W. Palmer, D. J. Tongway, H. Azarnivand, M. Jafari e M. Mohseni Saravi. "Plant species composition and soil characteristics around Iranian piospheres". Journal of Arid Environments 82 (luglio 2012): 106–14. http://dx.doi.org/10.1016/j.jaridenv.2012.02.004.

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Porembski, Stefan, e Aparna Watve. "Remarks on the species composition of ephemeral flush communities on paleotropical rock outcrops". Phytocoenologia 35, n. 2-3 (1 agosto 2005): 389–402. http://dx.doi.org/10.1127/0340-269x/2005/0035-0389.

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Lilieholm, Robert J. "Financial Risk and Desired Species Composition in Mixed Species Stands". Southern Journal of Applied Forestry 15, n. 4 (1 novembre 1991): 185–87. http://dx.doi.org/10.1093/sjaf/15.4.185.

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Abstract The use of historical stumpage price fluctuations in reducing the risk of future financial returns from mixed species stands is explored. It is demonstrated that if past stumpage values are indicative of future price behavior, silvicultural treatments designed to favor species with stable and/or negatively correlated stumpage values can reduce the variance of future harvest revenues and hence decrease the financial risks of growing timber. South. J. Appl. For. 15(4):185-187.

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T., Binish, e Pushpa R. "Pharmaceutical and nutraceutics on three endemic species of Ceropegia". Annals of Plant Sciences 7, n. 5 (30 aprile 2018): 2221. http://dx.doi.org/10.21746/aps.2018.7.5.3.

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Plants are the richest resource of drugs of traditional systems of medicine and modern medicines. Medicinal plant species has its own nutrient composition besides pharmacologically important phytochemicals. Nutraceutics is an emerging field of therapy. As we come to the end of this millennium, more and more people are getting health conscious are looking at dietary substances for preventive or curative effects. The importance of minerals such as potassium, calcium, sodium etc. to human health is well known.The nutritional values and mineral composition of medicinal plants are being used as dietary supplements by humans. The nutritional compositions of selected Ceropegia species were found as good nutritive value. Nutritive compositions were analyzed and compared in vitro plant parts of Ceropegia spiralis, Ceropegia candelabrum and Ceropegia juncea. Sixty to seventy five days old in vitro plants were taken for biochemical studies of total proteins, total carbohydrates, sugar, starch and amino acid.Among the three samples analyzed, high protein sugar and aminoacids content was noticed in Ceropegia juncea and total carbohydrates and protein values high in Ceropegia candelabrum, Ceropegia candelabrum was found to be a rich source of iron (18.55±0.11) followed by Ceropegia juncea (17.74±0.25) and Ceropegia spiralis (17.56±0.25).Nutraceuticals importance of these valuable plants may help in future for the production of new medicines and valuable food stuffs. The secondary metabolitices present in them give them a specific medicinal benefit other than a purely nutritional.These species are utilized for Indian system of medicine and scientists encourage them to rationalize it suiting the modern requirements of biotechnology.

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Kaplan, Mahmut, Kagan Kokten, Aydin Sukru Bengu, Yusuf Murat Kardes, Aydin Das e Akife Dalda Sekerci. "Fatty Acid Composition of Different Quercus Species". Chemistry of Natural Compounds 55, n. 2 (marzo 2019): 313–15. http://dx.doi.org/10.1007/s10600-019-02675-x.

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Kamysbaevа, A. K., e G. E. Azimbaeva. "Biologically active substances of some species of the genus Asteraceae". Bulletin of the National Engineering Academy of the Republic of Kazakhstan 1, n. 79 (15 febbraio 2021): 62–69. http://dx.doi.org/10.47533/2020.1606-146x.62.

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Currently, 40% of drugs used in modern medicine are obtained from plant raw materials. Among the wild flora there are medicinal plant species containing a variety of chemical composition, including biologically active substances with antimicrobial activity and phytoncidal properties. This article presents biologically active substances of some species of the genus Asteraceae . The chemical composition of plants belonging to the Asteraceae family is represented by anthocyanins, inulins, pectins, flavonoids, proteins, cloves, fatty oils, coumarins, carotenes and polyphenols. The plant of the Asteraceae family is used in folk medicine as an anti-inflammatory, antitumor and cardiotonic agent.

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Toland, D. C., C. P. West e M. E. Boyer. "MEDIA COMPOSITION INFLUENCES GREEN ROOF PLANT VIABILITY IN THE OZARK HIGHLANDS". Journal of Green Building 7, n. 4 (novembre 2012): 73–84. http://dx.doi.org/10.3992/jgb.7.4.73.

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Plant selection and establishment are critical components for green roof health and success. Plant palettes (sets of plant species selected for specific conditions) for green roofs vary in their ability to confer benefits depending on the species make-up and their adaptation to particular environments and climates. The response of various species to climatic factors on rooftops is unknown for the Ozark Highlands region. The objective of this study was to compare plant survival and spread in three growing medium treatments (course and fine texture with compost and fine texture with no compost) installed as part of a green roof system. The study was performed on a green roof system at the University of Arkansas in Fayetteville over 3 years. Data were collected on 13 species installed in September of 2006 and surveyed on three dates thereafter: April 30, 2007; May 19, 2009; September 10, 2009. The treatments with added compost had statistically greater vegetated cover (from 73 to 87%) compared to the fine medium without compost (36 to 43%). In most cases the spread of individual plants was not significantly different between treatments. Results indicated that rooting medium containing compost increased survival and overall vegetated roof coverage, and identified various potential green roof plant species for the Ozark Highland environment. Two species, Sedum middendorffianum var. diffusum and Sedum spurium ‘Roseum’, did particularly well in all treatments. One species, Sedum kamtschaticum, did well only in the treatments with compost.

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32

Müller, Stefan W., Hans-Peter Rusterholz e Bruno Baur. "Rock climbing alters the vegetation of limestone cliffs in the northern Swiss Jura Mountains". Canadian Journal of Botany 82, n. 6 (1 giugno 2004): 862–70. http://dx.doi.org/10.1139/b04-058.

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Exposed cliffs in the northern Swiss Jura Mountains harbour a highly diverse flora with numerous endangered and relic plant species. On these cliffs, sport climbing is enjoying increasing popularity. We examined the ecological effects of sport climbing on vascular plants at the cliff base and on the cliff face by assessing plant cover and species density at various distances from frequently used climbing routes. Plant cover was significantly reduced at the base of climbing routes. Furthermore, species density (number of species per square metre) at the cliff base, as well as plant cover and species density at the cliff face, tended to increase with distance from the route. We also compared the vegetation of five frequently climbed cliffs with that of seven unclimbed cliffs. Climbing significantly altered the plant composition. Specialized rock species occurred less frequently on climbed cliffs than on unclimbed cliffs. Management plans and conservation actions are needed to preserve the threatened plant species on frequently climbed cliffs. Such plans should include the establishment of climbing-free protection areas on cliffs with a high number of specialized, relic plants and the protection of entire cliffs that are not yet climbed.Key words: disturbance, vegetation, Jura Mountains, rock climbing, limestone cliff.

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33

Lososová, Zdeňka, Michaela Kolářová, Luděk Tyšer e Samuel Lvončík. "Organic, integrated and conventional management in apple orchards: effect on plant species composition, richness and diversity". Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 59, n. 5 (2011): 151–58. http://dx.doi.org/10.11118/actaun201159050151.

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The study was conducted to assess the effect of conventional, integrated and organic management on differences in plant species composition, richness and diversity. The plants were studied in triads of orchards situated in three regions of the Czech Republic. Data about species occurrences were collected on 15 permanent plots in the tree rows and 15 plots between tree rows in each of the apple orchards during 2009. A total of 201 vascular plant species (127 native species, 65 archaeophytes, and 9 neophytes) were found. Management type and also different regional conditions had a significant effect on plant species composition and on diversity parameters of orchard spontaneous vegetation. Species richness and species pool was significantly higher in the organic orchards than in the differently managed orchards. Management type had significant effect on proportions of archaeophytes, and also neophytes in apple orchards. The results showed that a change from conventional to integrated and organic management in apple orchards lead to higher plant species diversity and to changes in plant species composition.

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34

Iversen, L. L., A. Winkel, L. Baastrup-Spohr, A. B. Hinke, J. Alahuhta, A. Baattrup-Pedersen, S. Birk et al. "Catchment properties and the photosynthetic trait composition of freshwater plant communities". Science 366, n. 6467 (14 novembre 2019): 878–81. http://dx.doi.org/10.1126/science.aay5945.

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Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.

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35

Tretyakova, A. S., O. G. Baranova, N. N. Luneva, T. A. Terekhina, S. M. Yamalov, M. V. Lebedeva, G. R. Khasanova e N. Yu Grudanov. "Segetal flora of some regions of Russia: characteristics of the taxonomic structure". Proceedings on applied botany, genetics and breeding 181, n. 2 (28 giugno 2020): 123–33. http://dx.doi.org/10.30901/2227-8834-2020-2-123-133.

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The authors’ data on the weed species composition in 8 geographic regions of the Russian Federation were laid at the basis of this survey. The segetal flora comprised weeds of cereals, root crops, and perennial grasses. The composition and taxonomic structure of weed species were analyzed. The total number of weedy plants encompassed 686 plant species. The level of regional weed species diversity was positively related to the area planted. Altai Territory, Udmurtia, and Rostov Province had the greatest weed species diversity, with more than 300 species, while Vologda Province had the lowest diversity (193 species). Most species-rich plant families (Asteraceae Dumort., Poaceae Barnhart, Fabaceae Lindl., Brassicaceae Burnet), genera (Potentila L., Artemisia L., Veronica L., Chenopodium L., Silene L., Trifolium L.), their subsequences, contributions of singlespecies families (17–39%) and genera (57–74%) were relatively stable systematic structure indicators. Only 18% of the species were common for all the regions. In each region there were region-specific groups of species. Weed species compositions in geographically close regions – the European part of Russia and the Urals – showed the greatest similarity. As for geographically distant regions (Altai Territory and Rostov Province), their weedy species compositions were distant and contained large groups of region-specific species.

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36

Čepelová, Barbora, e Zuzana Münzbergová. "Factors determining the plant species diversity and species composition in a suburban landscape". Landscape and Urban Planning 106, n. 4 (giugno 2012): 336–46. http://dx.doi.org/10.1016/j.landurbplan.2012.04.008.

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37

Ehlers, Bodil K., Christian F. Damgaard e Fabien Laroche. "Intraspecific genetic variation and species coexistence in plant communities". Biology Letters 12, n. 1 (gennaio 2016): 20150853. http://dx.doi.org/10.1098/rsbl.2015.0853.

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Many studies report that intraspecific genetic variation in plants can affect community composition and coexistence. However, less is known about which traits are responsible and the mechanisms by which variation in these traits affect the associated community. Focusing on plant–plant interactions, we review empirical studies exemplifying how intraspecific genetic variation in functional traits impacts plant coexistence. Intraspecific variation in chemical and architectural traits promotes species coexistence, by both increasing habitat heterogeneity and altering competitive hierarchies. Decomposing species interactions into interactions between genotypes shows that genotype × genotype interactions are often intransitive. The outcome of plant–plant interactions varies with local adaptation to the environment and with dominant neighbour genotypes, and some plants can recognize the genetic identity of neighbour plants if they have a common history of coexistence. Taken together, this reveals a very dynamic nature of coexistence. We outline how more traits mediating plant–plant interactions may be identified, and how future studies could use population genetic surveys of genotype distribution in nature and methods from trait-based ecology to better quantify the impact of intraspecific genetic variation on plant coexistence.

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38

Mezgebe, Alemayehu Haiemicael, e Alemayehu Hailemicael Mezgebe. "Woody Species Composition Analysis of Shawo Sacred Forest, Ethiopia". International Journal of Applied Sciences and Biotechnology 7, n. 1 (11 febbraio 2019): 12–21. http://dx.doi.org/10.3126/ijasbt.v7i1.21978.

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In sacred forests of indigenous communities, landscapes are deemed sacred and are protected through social norms and spiritual values. The main objective of this study was to analyze the woody species composition of Shawo forest and explore the traditional governing systems that safeguard the sacred forest up to the present. Systematic sampling method was used to collect data. Accordingly, 42 quadrats each with 400 m2 (20 m X 20 m) was laid along the 14 transect lines. All woody plant species were collected and identified in each of these quadrats. Vegetation parameters such as DBH an Height of each quadrat were recorded. Interview and group discussion were held with local community to gather socio-cultural information. From the result, 16 plant species were found. The average plant density was 499 individual ha-1 with DBH and H value of 9.21 cm and 10.43 m respecitively.. The maximum mean plant height was 39.43 m (Syzygium guineense).The total basal area of all plant species was found to be 56.1 m2.ha-1. From the total plant species of Shawo forest Syzygium guineense has the largest basal area 35.77 m2.ha-1 (63.77%) occurring in all 42 plots. The most important plant species of Shawo forest was Syzygium guineense with important value index (IVI) of 151.7 contributing to 50.57% of total IVI. For future sustainability of Shawo forest, community traditional conservation practices should be appreciated and supported.

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39

Schweiger, Rabea, Eva Castells, Luca Da Sois, Jordi Martínez-Vilalta e Caroline Müller. "Highly Species-Specific Foliar Metabolomes of Diverse Woody Species and Relationships with the Leaf Economics Spectrum". Cells 10, n. 3 (13 marzo 2021): 644. http://dx.doi.org/10.3390/cells10030644.

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Plants show an extraordinary diversity in chemical composition and are characterized by different functional traits. However, relationships between the foliar primary and specialized metabolism in terms of metabolite numbers and composition as well as links with the leaf economics spectrum have rarely been explored. We investigated these relationships in leaves of 20 woody species from the Mediterranean region grown as saplings in a common garden, using a comparative ecometabolomics approach that included (semi-)polar primary and specialized metabolites. Our analyses revealed significant positive correlations between both the numbers and relative composition of primary and specialized metabolites. The leaf metabolomes were highly species-specific but in addition showed some phylogenetic imprints. Moreover, metabolomes of deciduous species were distinct from those of evergreens. Significant relationships were found between the primary metabolome and nitrogen content and carbon/nitrogen ratio, important traits of the leaf economics spectrum, ranging from acquisitive (mostly deciduous) to conservative (evergreen) leaves. A comprehensive understanding of various leaf traits and their coordination in different plant species may facilitate our understanding of plant functioning in ecosystems. Chemodiversity is thereby an important component of biodiversity.

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40

Caruthers, Jennet, e Diane Debinski. "Montane Meadow Butterfly Species Distributions in the Greater Yellowstone Ecosystem". UW National Parks Service Research Station Annual Reports 30 (1 gennaio 2006): 85–96. http://dx.doi.org/10.13001/uwnpsrc.2006.3657.

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The composition of butterfly communities is a good indicator of changing environmental conditions. Butterflies have tight associations with the plant community due to their dependence on plants throughout their life history. These associations make butterfly distributions predictable based on the plant communities. Butterfly abundance data have been collected annually since 1997 within montane meadow sites characterized along a hydrologic gradient within the Greater Yellowstone Ecosystem. From this research, community composition may be predictable relative to future climatic changes and key habitat constraints. Identifying such variables is important for butterfly conservation.

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41

Cheema, Simrita, Josef Zeyer e Ruth Henneberger. "Methanotrophic and Methanogenic Communities in Swiss Alpine Fens Dominated by Carex rostrata and Eriophorum angustifolium". Applied and Environmental Microbiology 81, n. 17 (19 giugno 2015): 5832–44. http://dx.doi.org/10.1128/aem.01519-15.

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ABSTRACTVascular plants play a key role in controlling CH4emissions from natural wetlands, because they influence CH4production, oxidation, and transport to the atmosphere. Here we investigated differences in the abundance and composition of methanotrophic and methanogenic communities in three Swiss alpine fens dominated by different vascular plant species under natural conditions. The sampling locations either were situated at geographically distinct sites with different physicochemical properties but the same dominant plant species (Carex rostrata) or were located within the same site, showing comparable physicochemical pore water properties, but had different plant species (C. rostrataorEriophorum angustifolium). All three locations were permanently submerged and showed high levels of CH4emissions (80.3 to 184.4 mg CH4m−2day−1). Soil samples were collected from three different depths with different pore water CH4and O2concentrations and were analyzed forpmoAandmcrAgene and transcript abundance and community composition, as well as soil structure. The dominant plant species appeared to have a significant influence on the composition of the active methanotrophic communities (transcript level), while the methanogenic communities differed significantly only at the gene level. Yet no plant species-specific microbial taxa were discerned. Moreover, for all communities, differences in composition were more pronounced with the site (i.e., with different physicochemical properties) than with the plant species. Moreover, depth significantly influenced the composition of the active methanotrophic communities. Differences in abundance were generally low, and active methanotrophs and methanogens coexisted at all three locations and depths independently of CH4and O2concentrations or plant species.

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42

Scognamiglio, Monica, Brigida D’Abrosca, Assunta Esposito e Antonio Fiorentino. "Chemical Composition and Seasonality of Aromatic Mediterranean Plant Species by NMR-Based Metabolomics". Journal of Analytical Methods in Chemistry 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/258570.

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An NMR-based metabolomic approach has been applied to analyse seven aromatic Mediterranean plant species used in traditional cuisine. Based on the ethnobotanical use of these plants, the approach has been employed in order to study the metabolic changes during different seasons. Primary and secondary metabolites have been detected and quantified. Flavonoids (apigenin, quercetin, and kaempferol derivatives) and phenylpropanoid derivatives (e.g., chlorogenic and rosmarinic acid) are the main identified polyphenols. The richness in these metabolites could explain the biological properties ascribed to these plant species.

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43

Otsu, Chiaki, Hayato Iijima e Takuo Nagaike. "Plant community recovery from intense deer grazing depends on reduction of graminoids and the time after exclosure installation in a semi-natural grassland". PeerJ 7 (1 ottobre 2019): e7833. http://dx.doi.org/10.7717/peerj.7833.

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Exclosures that exclude large herbivores are effective tools for the protection and restoration of grazed plant communities. However, previous studies have shown that the installation of an exclosure does not ensure plant community recovery. Our study aimed to determine the effects of the domination of unpalatable plants and the timing of exclosure installation on the plant community recovery process in montane grassland overgrazed by sika deer (Cervus nippon) in Japan. In this study we compared plant species composition and their cover with inside and outside exclosures installed at different times. Furthermore, we also compared them with those in 1981, when density of sika deer was very low. We used quadrats inside and outside fenced areas established in 2010 and 2011 to record both the cover and the height of species in each quadrat between 2011 and 2015. Plant cover, with the exception of graminoid species, increased in later years in all treatments. Non-metric multidimensional scaling (NMDS) plots showed significantly differentiated treatment trends. The species composition within the 2010 fenced area gradually shifted to greater similarity with the species composition reported in 1981. The plant community in the 2011 fenced area was slower to recover. Compositions of plant communities outside the fenced areas hardly changed from 2011 to 2015. Chao’s dissimilarity index decreased over time between the plant community surveyed between 2011 and 2015 and the past plant community in 1981 within the exclosures, and was higher in the 2011 fenced area than in the 2010 fenced area. In conclusion, we show that the reduction of graminoids and the time after exclosure installation were important for plant community recovery from deer grazing damage. A delay in exclosure installation of one year could result in a delay in plant community recovery of more than one year.

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44

Ghosh, Somdatta, D. Kuila e N. K. Verma. "Arbuscular mycorrhizal association and dependency determined the pioneer plant community, diversity structure and plant cover in two river bank under same climate". Brazilian Journal of Biological Sciences 6, n. 13 (2019): 453–65. http://dx.doi.org/10.21472/bjbs.061313.

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Early colonization of plants in an area is influenced mostly by climatic, edaphic and phytogeographic factors. As arbuscular mycorrhizae (AM) was associated with early invasion of land plants on earth, AM may have some role in defining the first seral community in any land. Two riverbanks were selected to study their pioneer plant community structure with species composition and diversity, soil characters and arbuscular mycorrhizal association; and correlations among these factors. Species composition, diversity and richness indices, active AM association of early colonizing plant species, soil texture, moisture, pH and E.C in two river banks differed. Similarity index for plant species between the two communities was poor. Diversity and richness indices were high in K site while evenness was high in R site. AM colonization and spore density correlated highly with plant cover and frequency in both riverbanks. Soil moisture showed a strong negative impact on mycorrhization, soil organic carbon showed little. Soil pH showed varied correlation in different sites. Early colonizing plants in R site with silt-loam soil with high moisture level are found poorly mycotrophic or nonmycotrophic; though plant cover correlated highly with mycotrophy in both sites. Plants in sandy soil of K site are highly mycotrophic and with high arbuscular and vesicular colonizations. The distribution of frequency in R site is highly deviated from Raunkiuer’s frequency class; in K site it is rather stable. The soil condition is only key factor to determine plant composition and plant-mycorrhizal relations influencing colonization of early seral community.

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45

McElroy, M. S., Y. A. Papadopoulos e M. S. Adl. "Complexity and composition of pasture swards affect plant productivity and soil organisms". Canadian Journal of Plant Science 92, n. 4 (luglio 2012): 687–97. http://dx.doi.org/10.4141/cjps2011-147.

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McElroy, M. S., Papadopoulos, Y. A. and Adl, M. S. 2012. Complexity and composition of pasture swards affect plant productivity and soil organisms. Can. J. Plant Sci. 92: 687–697. The relationships between ecosystem diversity, productivity, and stability is a central theme in current ecological research; the links between above-ground and below-ground ecosystems, as well as their effects on ecosystem services, are becoming more understood. While plant communities differ in primary productivity, and in the communities of soil organisms they support, it is unclear whether these differences are attributable mainly to plant community diversity or to the dominant plant species. This study evaluated the effect of these two factors on plant productivity, and abundance of soil microorganisms and functional diversity, in an establishing pasture using sward complexity (plant species present) and sward composition (identity of species) as treatments in a design using the step-wise addition of grass species. While sward complexity affected plant productivity, showing higher productivity in plots of higher diversity, abundance and functional diversity of soil organism groups were generally not consistently affected by sward complexity or composition. Sward composition did influence soil community composition; there was a close correlation between microbial catabolic activity and sward composition. This study shows that grassland plants have a limited effect on the size and diversity of soil communities while they are being established. This result may have consequences for soil ecosystem services.

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46

Zul, Delita, Sabine Denzel, Andrea Kotz e Jï¿½rg Overmann. "Effects of Plant Biomass, Plant Diversity, and Water Content on Bacterial Communities in Soil Lysimeters: Implications for the Determinants of Bacterial Diversity". Applied and Environmental Microbiology 73, n. 21 (14 settembre 2007): 6916–29. http://dx.doi.org/10.1128/aem.01533-07.

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ABSTRACT Soils may comprise tens of thousands to millions of bacterial species. It is still unclear whether this high level of diversity is governed by functional redundancy or by a multitude of ecological niches. In order to address this question, we analyzed the reproducibility of bacterial community composition after different experimental manipulations. Soil lysimeters were planted with four different types of plant communities, and the water content was adjusted. Group-specific phylogenetic fingerprinting by PCR-denaturing gradient gel electrophoresis revealed clear differences in the composition of Alphaproteobacteria, Betaproteobacteria, Bacteroidetes, Chloroflexi, Planctomycetes, and Verrucomicrobia populations in soils without plants compared to that of populations in planted soils, whereas no influence of plant species composition on bacterial diversity could be discerned. These results indicate that the presence of higher plant species affects the species composition of bacterial groups in a reproducible manner and even outside of the rhizosphere. In contrast, the environmental factors tested did not affect the composition of Acidobacteria, Actinobacteria, Archaea, and Firmicutes populations. One-third (52 out of 160) of the sequence types were found to be specifically and reproducibly associated with the absence or presence of plants. Unexpectedly, this was also true for numerous minor constituents of the soil bacterial assemblage. Subsequently, one of the low-abundance phylotypes (beta10) was selected for studying the interdependence under particular experimental conditions and the underlying causes in more detail. This so-far-uncultured phylotype of the Betaproteobacteria species represented up to 0.18% of all bacterial cells in planted lysimeters compared to 0.017% in unplanted systems. A cultured representative of this phylotype exhibited high physiological flexibility and was capable of utilizing major constituents of root exudates. Our results suggest that the bacterial species composition in soil is determined to a significant extent by abiotic and biotic factors, rather than by mere chance, thereby reflecting a multitude of distinct ecological niches.

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47

Butkutė, Bronislava, Audrius Padarauskas, Jurgita Cesevičienė, Lukas Taujenis e Eglė Norkevičienė. "Phytochemical composition of temperate perennial legumes". Crop and Pasture Science 69, n. 10 (2018): 1020. http://dx.doi.org/10.1071/cp18206.

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A deeper understanding of the phytochemical composition of perennial legumes is important for animal nutrition as well as for the development of pharmaceuticals. The present study is an assessment of perennial legumes including clovers (Trifolium pratense L. and T. medium L.), medics (Medicago sativa L. and M. lupulina L.), sainfoin (Onobrychis viciifolia Scop.) and milkvetches (Astragalus glycyphyllos L. and A. cicer L.) as potential sources of bioactive compounds. Whole aerial parts of plants at stem elongation and full-flowering stages as well as morphological parts of fully flowering plants (leaves, stems and flowers) were analysed for four isoflavones (biochanin A, daidzein, formononetin, and genistein), coumestrol, condensed tannins and triterpene saponins. According to total concentration of the four isoflavones in plants, the species were ranked as follows: T. medium (23.2–28.7 mg g–1 DM) > T. pratense > A. glycyphyllos = A. cicer = O. viciifolia = M. sativa = M. lupulina (0.054–0.212 mg g–1 DM). Young plants were 1.2–5.6-fold richer in isoflavones than fully flowering plants. Quantifiable concentrations of coumestrol and saponins were found in the Medicago species and tannins in O. viciifolia. In general, leaves contained the highest concentrations of the phytochemicals. These findings suggest considerable potential to improve legume-based forage quality through appropriate exploitation of species- or cultivar-specific phytochemicals and manipulation of the content of phytochemicals by management of production including growth stage at harvest and selection of plant species.

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48

Dangol, DR. "Species Composition, Distribution, Life Forms and Folk Nomenclature of Forest and Common Land Plants of Western Chitwan, Nepal". Journal of the Institute of Agriculture and Animal Science 26 (1 aprile 2005): 93–105. http://dx.doi.org/10.3126/jiaas.v26i0.662.

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This paper enumerates 349 plant species belonging to 77 families of vascular plants collected in the winter seasons of 1996 and 2000 by the flora teams of the Population and Ecology Research Laboratory, Nepal. Of the total species, 249 species belong to dicotyledons, 87 species to monocotyledons and 13 species to pteridophytes. Among the families, dicotyledons contributed the highest number of families (55 in number) followed by monocotyledons and pteridophytes. In the study areas, species composition varies with the type of habitats in the study plots. Some species are unique in distribution. The highest unique species are contributed by common lands (87 spp.), followed by the Chitwan National Park forest (36 spp.) and Tikauli forest (32 spp.). Ageratum houstonianum Mill., Cynodon dactylon (L.) Pers., Imperata cylindrica (L.) Beauv., Rungia parviflora (Retz.) Nees, Saccharum spontaneum L. and Thelypteris auriculata (J. Sm.) K. Iwats are the most common species across all the research blocks. Of the listed plants, many plants have local names either in Nepalese or other tribal languages. Plants are named in different ways on the basis of habit, habitat, smell, taste, and morphological characters of the plants, which are also the basis of nomenclature in plant taxonomy. Key words: Folk name, plant biodiversity, plant distribution, species composition analysis J. Inst. Agric. Anim. Sci. 26:93-105 (2005)

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49

Strong, W. L. "Secondary vegetation and floristic succession within a boreal aspen (Populus tremuloides Michx.) clearcut". Canadian Journal of Botany 82, n. 11 (1 novembre 2004): 1576–85. http://dx.doi.org/10.1139/b04-120.

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The composition and abundance of vascular plants within a boreal Populus tremuloides Michx. stand in west-central Alberta were assessed three, five, nine, and 20 years after clearcutting. Rapid re-establishment of Populus tremuloides and other species such as Amelanchier alnifolia (Nutt.) Nutt. ex M. Roemer and Rosa acicularis Lindl. occurred primarily in response to vegetative propagation. Some minor compositional variability occurred among the year 3 plots (n = 88), but they were considered members of the same plant community, with 88% of the plots undergoing similar developmental processes during the course of the study. Some dominant species substantially increased in canopy cover, although most species maintained a relatively consistent level of abundance over time. Floristic richness was similar in year 3 (64 species) and year 20 (62 species) with the survival of 52 initiating species in year 20. The variability in floristic richness included the invasion of 32 species and the extirpation of 34 species. Stand development over a 20-year period best fit a tolerance model of succession because of the rapid development of dominant species, the lack of a major understory composition change, and a similar degree of dominance concentration among species. Understory vegetation growth was constrained by overstory shading.Key words: plant community, tolerance model, secondary succession.

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50

Jaroszewicz, Bogdan, Ewa Pirożnikow e Ruth Sagehorn. "The European bison as seed dispersers: the effect on the species composition of a disturbed pine forest community". Botany 86, n. 5 (maggio 2008): 475–84. http://dx.doi.org/10.1139/b08-012.

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We studied the process of change in plant species composition in a pine–spruce forest influenced by endozoochorous seed dispersal by the European bison Bison bonasus L. The intensity of endozoochory was 3.4 times higher in the open tree stand than in the surrounding undisturbed forest (t = –3.0836, df = 50, P = 0.003). Over 1578 individuals/ramets belonging to 23 vascular plant taxa developed on 114 bison dung piles. The process of colonization included two plant species that have never before been recorded in the studied forest community. Seven out of 14 species transferred by bison were small-seeded herbaceous plants without morphological adaptations for long-distance dispersal. The majority of plant species recorded on the bison dung (55.9%) occur in deciduous forests. In contrast, over 50% of the plants surrounding bison faeces represented species of coniferous forests. The PCA analysis revealed the existence of two distinct groups of plant species: within bison faeces and on random systematic samples. The Jaccard coefficient of species composition similarity between them was 0.28. Our results demonstrate that the European bison is an effective vector of plant propagules between plant communities. This fact could have great importance for the restoration of degraded habitats, and could also introduce the risk of invasion by alien species.

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