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Podzemní biomasa ostřice štíhlé (\kur{Carex acuta\kur{}}) v travinném mokřadu / Below-ground biomass of \kur{Carex acuta} in a graminoid wetlandNEŠPOR, Marek January 2015 (has links)
This thesis is part of the project GA CR P504 / 11/1151 "The role of plants in the greenhouse gas balance Carex fens". The aim of this thesis is to evaluate the seasonal dynamics of Carex acuta belowground biomass in model grassland wetlands (the "wet meadows") near Třeboň. Belowground biomass of C. acuta L. was sampled using the destructive method. The samples were taken on four dates in 2014. On each date, three hummocks of C. acuta and three soil samples in their immediate vicinity were sampled on each date. Live roots had a greater dry weight than decaying roots on all sampling dates. Their total dry weight varied slightly, depending on season. The ratio of live roots to decaying roots did not differ much. The weight of live roots in hummock was almost always higher than that of the dead ones. The dry weight of living roots was always greater in the hummock than below it. Their total weight varied slightly during the year. Aquatic roots formed only a small part of the dry weight of live roots in hummocks. A greater total belowground dry weight found on 21st December 2014, in comparison with 5th August 2014, was associated with a greater amount of rhizomes of other plant species. The shoots increased their dry weight during the year. Maximum weight of tillers was recorded on 8th August 2014. There were no dead shoots on 25th March 2014. Dry weights of dead tillers were largely similar throughout the year. The volumetric soil water content (%) was usually higher in the upper soil layers. The bulk density of the soil was almost identical on all sampling sites, except for the top layer on site 1, where it was considerably lower.
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Facteurs influençant le succès de la restauration des populations de carex faux-lupulinaLanglois, Annabelle 01 1900 (has links)
Ce mémoire visait à déterminer les pratiques et les facteurs favorables au succès des réintroductions du carex faux-lupulina (Carex lupuliformis), une espèce vivace menacée poussant dans divers types de milieux humides ouverts du nord-est de l’Amérique du Nord. Pour répondre à cet objectif, des expériences de germination en serres ont été réalisées, et la survie, la vigueur et le microhabitat de chaque plant de carex faux-lupulina connu au Québec (sauvage ou réintroduit) ont été mesurés. Nos résultats montrent que le carex faux-lupulina est une espèce facile à propager ex situ. Une stratification froide (4°C) des semences dans du sable humide pendant un mois induit des taux de germination élevés. Nos résultats montrent également que des pucerons exotiques, ainsi qu’une transplantation dans des habitats inadaptés aux besoins de l’espèce en termes d’humidité du sol et de lumière disponible, ont causé la mort prématurée d’un grand nombre de transplants. Notre programme de réintroduction a permis d’établir une nouvelle population de l’espèce au Québec, et a potentiellement permis de sextupler la taille des populations de la province. Globalement, cette étude a permis de mieux comprendre l’écologie du carex faux-lupulina, et ainsi de faciliter la restauration de ses populations. / This study aimed to determine the practices and factors influencing the success of the reintroductions of false hop sedge, an endangered perennial species growing in North American open wetlands. To do so, germination experiments were performed, and the survival, vigour and microhabitat of each false hop sedge plant known in Québec (wild or reintroduced) were measured. Our results show that false hop sedge is easy to propagate ex situ. A cold stratification (4°C) of seeds in wet sand for one month induced higher germination rates. Our results also show that exotic aphids, as well as a transplantation in habitats that did not meet the false hop sedge requirements in terms of soil moisture and available light, caused
the premature death of many transplants. Our reintroduction program allowed the establishment of at least one new false hop sedge population in Québec, and potentially contributed to sextupling the size of the provincial population. Overall, this study allowed us to better understand the ecology of false hop sedge, and thus facilitate the restoration of its populations.
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Přispívá vodní stres a mezidruhová konkurence k funkční konvergenci nebo divergenci vlastností mokřadních rostlin? / Does water stress and interspecific competition contribute to the functional divergence or convergence of wetland plant species?Műnichová, Radka January 2017 (has links)
This diploma thesis is based on the experiment which took 5 years. In 52 plastic containers were planted four species wetland plants; two species of grasses (Calamagrostis canescens and Deschampsia cespitosa) and two species of sedges (Carex elata and Carex elongata). Three types of water regime were set up with: high, low and fluctuating water level, where the high and low level of water took turns after one year. One year before the data collection the strongest competitor Carex elata was cut out. For the evaluation of the role of water level (environmental stress) and removal of the dominant (competition) we selected two functional trait indicators: specific leaf area (SLA) and leaf dry matter content (LDMC). SLA is an indicator of resource strategies, competitiveness and efficiency of light photosynthesis. Species with high SLA are usually better competitors for light, but tolerate harder the environmental stress. LDMC reflects a plants investment in persistent leaf structures and therefore in nutrient retention. A significant effect of water regime on LDMC was observed in the species Deschampsia cespitosa that had higher average values of LDMC in dry water regime, which is indicating higher investment into persistent leaf structures. And the effect of the dominant removal on SLA, where the values of SLA in the containers without removed dominant were higher. Increased SLA implies increased intensity of competition for light. My diploma thesis supported that specific leaf area and leafdry matter content are important functional indicators different types of stress conditions in wetland communities.
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Строение корней осок из местообитаний с разной степенью увлажнения : магистерская диссертация / Structure of sedge roots from hab-its with different degrees of humidificationТукова, Д. Е., Tukova, D. E. January 2021 (has links)
Магистерская диссертация на тему «СТРОЕНИЕ КОРНЕЙ ОСОК ИЗ МЕСТООБИТАНИЙ С РАЗНОЙ СТЕПЕНЬЮ УВЛАЖНЕНИЯ» состоит из 52 страниц машинописного текста, включая 19 рисунков, 2 таблицы и 113 литературных источников. Работа посвящена изучению морфологического и анатомического строения корней осок из местообитаний с разной степенью увлажнения и разных экоморф, или экологических групп по отношению к увлажнению. В исследованный материал входят собственные сборы и зафиксированные растительные образцы научных руководителей. Цель – изучение строения корней осок из местообитаний с разной степенью увлажнения и разных экоморф по отношению к увлажнению. Задачи: Изучить внешние признаки корневых систем и строение поглощаю-щих корней у осок разных экоморф и местообитаний; Установить, какие признаки и в какой степени связаны с экоморфой видов, а какие изменяются под действием режима увлажнения местообитаний независимо от принадлежности к экоморфе. Растения собраны в начале июня в период цветения большинства исследован-ных видов 2019-2021 гг. в местообитаниях, образующих градиент по увлажнению: водоем-луг-лес-сухой склон. Экологические группы по степени увлажнения среды (гигрофиты, мезофиты, ксеромезофиты) выделены по литературному источнику [Овеснов и др., 2007]. С помощью стандартных методик структурной ботаники изучены внешние признаки корневых систем и строение поглощающих корней 23 вида осок. Регистрировали параметры: число порядков ветвления корней, тип волосков, длина типичных волосков, диаметр корня; диаметр стелы; толщину паренхимы; число слоев клеток в паренхиме; число слоев клеток в экзодерме, толщину коры. Расчетные показатели – парциальный объем коры и стелы, %. В работе представлены 2 способа формирования учетных единиц. При анализе экологических групп, учетной единицей считается вид. Исследуя группы осок из местообитаний с разной степенью увлажнения, учетной единицей считается особь. Статистический анализ проводился с помощью программы STATISTICA 10. Использовали однофакторный дисперсионный анализ (F) (ANOVA) Непараметриче-ские критерии Краскела –Уоллиса (H) и Критерий (χ2) Пирсона. Результаты магистерской диссертации показали, что признаками тонких корней изученных осок, наиболее чувствительными к режиму увлажнения, являются: число порядков ветвления корней; встречаемость выпуклых корневых волосков; длина типичных корневых волосков; диаметр среза, толщина коры; выраженность экзодермы; У изученных осок от переувлажненных местообитаний к засушливым: а) увеличивается число порядков ветвления корней; б) уменьшаются: встречаемость выпуклых корневых волосков, длина корневых волосков, диаметр среза, толщина первичной коры за счет уменьшения слоев экзодермы. Несмотря на таксоноспецифичное строения корней осок, существует явно выраженная экологическая пластичность ряда признаков внутри обширного рода Carex. Полученные результаты согласуются с опубликованными данными. Результаты были представлены в устном докладе на Всероссийской конференции молодых ученых «Экология: факты, гипотезы, модели», проходившей в апреле 2021 года. Планируется публикация данных в сборнике конференции в виде тезисов. / The master's thesis on the topic "STRUCTURE OF SEDGE ROOTS FROM HAB-ITS WITH DIFFERENT DEGREES OF HUMIDIFICATION" consists of 52 pages of typewritten text, including 19 figures, 2 tables and 113 literature sources. The work is devoted to the study of the morphological and anatomical structure of sedge roots from habitats with varying degrees of moisture and different ecological groups. The analysis of the work consists of materials from our collection and recorded plant material [Konoplenko et al., 2017]. The goal is to study the structure of sedge roots from habitats with varying degrees of moisture and different ecomorphs in relation to moisture. Tasks: 1) To study the external signs of root systems and the structure of absorbing roots in sedges of different ecomorphs and habitats; 2) Establish which features and to what extent are associated with the ecomorph of the species, and which ones change under the influence of the habitat moistening regime, regardless of belonging to the ecomorph. To tackle these problems, the plants were collected in habitats forming a moisture gradient: reservoir-meadow-forest-dry slope. The ecological groups of sedge species were identified according to the literature [Ovesnov et al., 2007] according to the degree of en-vironmental moisture: hygrophytes, mesophytes, Xeromesophytes. Using the methods of structural botany, the external signs of root systems and the structure of absorbing roots of 23 species of sedges were studied. The following parameters were recorded: the number of orders of root branching, hair type, length of typical hairs, root diameter; stele diameter; parenchyma thickness; the number of cell layers in the parenchyma; the number of cell layers in the exoderm, the thickness of the cortex. Integral indicators - the partial volume of the cortex and ste-le,%. Statistical analysis was carried out using the STATISTICA 10 program. One-way analysis of variance (F) (ANOVA) was used. Nonparametric Kruskal-Wallis tests (H) and Pearson's test (χ2). The results of the master's thesis showed that the features of the thin roots of the studied sedges, the most sensitive to the moisture regime, are:the number of orders of root branching; the occurrence of convex root hairs; length of typical root hairs; cut diameter, bark thickness; the severity of exoderm; In the studied sedges, from waterlogged to arid habitats: a) the number of orders of branching of roots increases; b) decrease: the occurrence of convex root hairs, length of root hairs, cut diameter, thickness of the primary cortex due to a decrease in exoderm layers. Despite the taxon-specific structure of sedge roots, there is a pronounced ecological plasticity of a number of characters within the vast genus Carex. The results obtained are consistent with published data. These results were presented in an oral report at the All-Russian Conference of Young Scientists "Ecology: Facts, Hypotheses, Models", held in April 2021. It is planned to publish data in the conference collection in the form of abstracts.
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Experimental studies in Carex section AcutaeFaulkner, John Stewart January 1970 (has links)
No description available.
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O gênero Carex L.(Cyperaceae) no Rio Grande do Sul, BrasilSilveira, Gabriela Hoff January 2010 (has links)
(O gênero Carex L. (Cyperaceae) no Rio Grande do Sul, Brasil) - O gênero Carex L. inclui cerca de 2200 espécies distribuídas principalmente em regiões frias e temperadas. Foi realizado o levantamento deste gênero no Rio Grande do Sul com base em coletas, revisão de herbários e de bibliografia. Foram confirmadas para o Estado: C. aureolensis Steud., C. bonariensis Desf., C. brasiliensis A.St.-Hil., C. brongniartii Kunth, C. chilensis Brongn., C. feddeana H. Pfeiff., C. fuscula ssp. catharinensis (Boeck.) Luceño & Alves, C. longii ssp. meridionalis (Kük.) Luceño & M. Alves, C. phalaroides ssp. crassiflora (Kük.) Luceño & M. Alves, C. phalaroides ssp. moesta (Kunth) Luceño & M. Alves, C. phalaroides ssp. paraguayensis (Maury) Luceño & M. Alves, C. phalaroides Kunth ssp. phalaroides, C. polysticha Boeck., C. purpureovaginata Boeck., C. sellowiana Schltdl., C. seticulmis Boeck., C. sororia Kunth, C. tweediana Nees ex Hooker, C. uruguensis Boeck. e C. vixdentata (Kük.) G.A. Wheeler. É fornecida uma chave analítica para a identificação dos táxons confirmados, bem como descrições, ilustrações e dados sobre distribuição geográfica geral e no Rio Grande do Sul. / (The genus Carex L. (Cyperaceae) in Rio Grande do Sul, Brazil) - The genus Carex L. includes about 2200 species mainly distributed in cold and temperate regions. A survey of the genus Carex in Rio Grande do Sul was carried out based on field collections, revision of herbaria and literature. The following taxa were confirmed to the State: C. aureolensis Steud., C. bonariensis Desf., C. brasiliensis A.St.-Hil., C. brongniartii Kunth, C. chilensis Brongn., C. feddeana H. Pfeiff., C. fuscula D’Urv. ssp. catharinensis (Boeck.) Luceño & Alves, C. longii ssp. meridionalis (Kük.) Luceño & M. Alves, C. phalaroides ssp. crassiflora (Kük.) Luceño & M. Alves, C. phalaroides ssp. moesta (Kunth) Luceño & M. Alves, C. phalaroides ssp. paraguayensis (Maury) Luceño & M. Alves, C. phalaroides Kunth ssp. phalaroides, C. polysticha Boeck., C. purpureovaginata Boeck., C. sellowiana Schltdl., C. seticulmis Boeck., C. sororia Kunth, C. tweediana Nees ex Hooker, C. uruguensis Boeck. and C. vixdentata (Kük.) G.A. Wheeler. An analytical key to the identification of the confirmed taxa is provided as well as descriptions, illustrations and data on geographical distribution and habitat.
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Phytoécologie et phylogéographie des pelouses alpines à Carex curvula des montagnes carpatiques. Comparaison avec les autres montagnes du Système AlpinPuscas, Mihai 18 May 2008 (has links) (PDF)
Les pelouses alpines à Carex curvula (laîche courbée) constituent l'une des formations les plus emblématiques de l'étage alpin des montagnes européennes. Cette thèse se présente comme une contribution à l'étude des patrons de la diversité génétique de Carex curvula et des patrons de la diversité floristique des pelouses alpines à Carex curvula en Europe.<br /> Dans un premier temps, ce travail examine la variabilité floristique des pelouses dominées par C. curvula et tente d'identifier les forces qui ont joué le rôle le plus important dans la structuration des espèces de l'étage alpin acidiphile européen. Les résultats des analyses montrent qu'il existe une variabilité importante pour la distribution de la diversité interspécifique et seulement une correspondance partielle entre la position des barrières biogéographiques de l'étage alpin et les grandes distances géographiques qui séparent les massifs montagnards. Il ressort nettement que les forces qui ont joué le rôle le plus important dans la structuration floristique de l'étage alpin acidiphile européen sont de nature historique et dans une moindre mesure de nature écologique.<br /> Ensuite, nous explorons la distribution de la diversité génétique dans les populations de C. curvula dans un contexte phylogéographique. L'impact des glaciations quaternaires correspond à deux histoires différentes pour les flores alpines dans les montagnes de l'ouest et de l'est du continent européen. Chez C. curvula, les mécanismes de recolonisations postglaciaires auraient impliqué un large vague de migration est-ouest dans les Alpes et une migration verticale beaucoup plus locale dans les Carpates. Les Pyrénées auraient été colonisé plus récemment, à partir d'un refuge secondaire localisé dans les Alpes du Sud-Ouest.<br /> Enfin, dans un troisième temps, nous nous intéressons au problème des relations entre la diversité génétique et floristique, en analysant la diversité locale des espèces dans les pelouses à C. curvula et la diversité génétique de l'espèce dominante. Le manque de corrélation positive entre les deux niveaux de la diversité est expliqué par des réponses différentes des gènes et des espèces aux grands changements climatiques qui sont intervenus au cours du Quaternaire.<br /> Nous concluons sur les perspectives de biogéographie comparative ouvertes par ce travail, en particulier sur l'articulation souhaitée entre les efforts de modélisation de la distribution biologique, la phylogéographie et l'écologie évolutive.
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De läste Dårhushjonet! : Laestadiansk ungdomsväckelse i Sverige 1970-1978Enbuska, Emil January 2012 (has links)
Föreliggande studie söker utröna vad som konstituerade den laestadianska ungdomsväckelsen i Sverige 1970-1978. Studien tar ett perspektiv inifrån väckelsen, och bygger på i första hand på ett antal kvalitativa intervjuer med centrala personer i väckelsen. Dessa intervjuer har utförts enligt en intervjuguide, där frågorna kretsat runt ett antal centrala kriterier för hur väckelsens konstituerande element ska upptäckas. Kriterierna vilar i sin tur på teorier runt väckelsebegreppet. Studien finner att väckelsen kan sägas ha varit en inom-laestadiansk akademisk väckelse med vissa karismatiska drag. Ungdomsväckelsen hade en tydlig ekumenisk inriktning. Vidare utvärderas också själva kriterierna som använts, och dessa tycks väl fylla sin uppgift.
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The effect of soil fertility on the growth of Carex species from temperate forest environments /Reygadas, Fabiola. January 1998 (has links)
This study compared the effect of two contrasting nutrient environments on the growth rates of 12 Carex species from the Mont St. Hilaire Biosphere Reserve, Quebec. All species demonstrated higher growth rates under conditions of high nutrient availability. There was no correlation found between maximum relative growth rate (RGRmax), leaf production, and biomass. High nutrient availability produced a reduction in root/shoot ratio, while leaf production was the trait that showed the greatest response to contrasts in nutrient availability The Carex species were found to be relatively slow growing plants, with growth potential ranging from stress tolerant to competitive. The species from lowlands are more competitive and have higher growth rates; the upland species are more stress tolerant and have lower growth rates. The abundance of a species at Mont St. Hilaire was found to be unrelated to its growth potential.
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Environmental niche partitioning among riparian sedges (Carex, Cyperaceae) in the St. Lawrence Valley, QuebecPlourde, Laura. January 2007 (has links)
To understand maintenance of the within-habitat diversity of closely related species, I investigated 11 Carex species growing along rivers in the south-western St. Lawrence Valley of Quebec. Microenvironments within a half meter of focal plants characterized for Carex comosa, C. crinita, C. grayi, C. intumescens, C. lacustris, C. lupulina, C. pseudocyperus, C. retrorsa, C. tuckermanii, C. typhina, and C. vesicaria revealed significant differences among the species in their environmental affinities. Species appear to fall into groups based on their tolerance of flooding and are secondarily differentiated on other environmental gradients such as insolation, soil pH and soil organic matter. Several traits were related to the environments that species inhabit: diaspore weight, diaspore floating duration, and root aerenchyma. The absence of any phylogenetic trend in niche differences for pairs of species supports the idea that evolutionary differentiation of the alpha-niche is the basis for coexistence of congeners.
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