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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Production, photosynthesis, and the storage and utilization of reserves in a natural stand of Typha latifolia L

Gustafson, Todd Douglas, January 1976 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 96-102).
2

THE ECOLOGY OF A DOMINANT EMERGENT (TYPHA LATIFOLIA) IN A RESERVOIR

Hallock, Robert James, 1943- January 1973 (has links)
No description available.
3

Phytoremediation of lead-contaminated soil using Typha latifolia (broadleaf cattail) /

McDonald, Steven. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 57-62). Also available via Humboldt Digital Scholar.
4

Managing Cattail (Typha latifolia) Growth in Wetland Systems

Sharp, Jessica Little 08 1900 (has links)
Nutrient availability, water depth, competition, and soil management effects on cattail (Typha latifolia) growth in wetland systems were examined. Soluble reactive phosphorous (SRP), nitrate-nitrogen (NO3-N), and ammonia-nitrogen (NH3-N) removals were tested at a constructed wetland receiving municipal wastewater effluent. Over all, no significant differences in nutrients occurred between diverse planted and cattail areas. T. latifolia seeds, under the canopy of Eleochoris macrostachya, had low seed germination. Established stands of emergent vegetation can prevent cattail colonization and spread. Germination of T. latifolia at various water depths was tested, and depth impacts on cattail seedling growth and survival were ascertained using various moist soil management techniques in three ponds. Water levels at 0cm and >40cm can adversely impact cattail establishment.
5

Distribution and environmental associations throughout southwestern Manitoba and southeastern Saskatchewan for the cattail species Typha latifolia, and T. angustifolia, and for the hybrid, T. x glauca

Wasko, Jennifer 23 April 2014 (has links)
Cattails (Typha spp.) are invasive and tend to decrease the biodiversity and area of open water of marshes, particularly where the natural hydrological cycles have been altered, as in Delta Marsh, Manitoba. Understanding the distribution of T. latifolia L., T. angustifolia L., their hybrid, T. x glauca Godr., and the environmental variables associated with their habitats, may give valuable insight for managing cattails. The distribution of these cattail species and hybrid were surveyed in 2011 in prairie pothole and roadside ditch marshes across southwestern Manitoba and southeastern Saskatchewan. Plants were identified by analysis of microscopic leaf-lamina margin characteristics. T. x glauca was most widespread, followed by T. latifolia, whereas T. angustifolia was rare and only found as far west as central Manitoba. Current understanding of the correlations between cattail invasions and their environment is conflicting and largely based on lacustrine wetland studies. A generalized linear model was developed. The model explained approximately 40% of the variation in T. x glauca distribution in the prairie potholes and ditches. The model included the environmental variables of sediment Olsen-P, sediment nitrate-N, water pH, litter depth, surrounding land use, and the interaction between Olsen-P and nitrate-N. Olsen-P was the most important of these variables, because its removal from the model significantly reduced the residual deviance of the model (P=0.05). In a survey of 13 transects throughout Delta Marsh in 2009, hybrid cattail, T. x glauca, was dominant, T. angustifolia was rare, and T. latifolia was absent. ANOVA linear regression (P=0.05) revealed that above-ground biomass was correlated with mean cattail ramet height, cattail ramet density, and standing litter biomass. Cattail ramet density was negatively correlated with sampling date and positively correlated with standing litter biomass. Mean cattail height was correlated with fallen litter biomass. One-way ANOVA (P=0.05) revealed that fallen litter biomass was lowest in quadrats closer to the open water, and mean cattail height was greatest at the quadrats closest to the open water. While mean cattail height differed depending on whether the cattail stand was a hybrid monoculture or a mixed stand of T. x glauca and T. angustifolia, no other cattail population variables were correlated with stand type. As revealed by one-way ANOVA (P=0.05), water conductivity, sediment texture, total-N, nitrate-N, Olsen-P, and organic-C were not important variables in the distributions of T. x glauca or T. angustifolia at Delta Marsh. Therefore, managing the nutrient levels at Delta Marsh would not likely be important for limiting the distribution of the cattails at this marsh. However, reducing the P concentration in pothole and ditch marshes may limit cattails in those environments.
6

GHG reduction by rewetted arable land : a study on cultivated peatland for biogas production in temperate climate in Sweden

Martens, Mireille LMI January 2017 (has links)
Hydrophytes can be cultivated on rewetted drained peatland and used as substrate to produce biogas which can be utilized as vehicle fuel. This results in less GHG from rewetted peat soils and at the same time leads to renewable energy that substitutes fossil fuels. A literature research was conducted to study the impact of different species (Phragmites australis = Pa and Typha latifolia=Tl) and soil nutrient status on GHG emissions of rewetted fens in N Europe. In addition, biogas production and the exposure to different N-load were investigated for these species. Pa has a methane yield of 235 ml CH4 g-1 VS-1 regardless the input of N whereas Tl needs to be fertilized in order to produce high methane yield (204 ml CH4 g-1 VS-1).  Pa sequesters more CO2 and converts it into biomass which makes it a C-sink but by using the GWP factor to convert CH4 into CO2-equivalents, Pa becomes as Tl a GHG-source. Still Pa’s GHG emissions are lower than Tl’s if water depth is maximum 20 cm. Pa also contributes to peat formation and can cope with water fluctuations.
7

Impact des éléments trace métalliques sur le milieu et apport de la cytométrie en flux dans l'étude du fonctionnement des lagunes de la décharge d'Etueffont (Territoire de Belfort, France) / Impact of the trace metal element on the environnment and the contribution of flow cytometry to the study of functioning of the lagoons discharge of Etuffont (Territory of Belfort, France

Al Ashoor, Ahmed Shaker 14 December 2016 (has links)
L’objectif de ce travail de thèse est d’évaluer le degré de contamination des différents compartiments du site de la décharge d’Étueffont à savoir : les lixiviats, les sédiments, l’eau souterraine, les poissons, les insectes et les microorganismes de la décharge d’Étueffont. Ce travail de recherche est structuré en neuf chapitres.Après une première partie (Part I) consacrée à une étude bibliographique, le deuxième chapitre (Part II) présente le site d’étude, c’est-à-dire l’installation de stockage de déchets non dangereux(ISDND) d’Étueffont. La troisième partie (Part III) est consacrée à l’analyse de la qualité des lixiviats dans les lagunes, les unités de stockage des déchets « Nouveau casier », « Sous casier », « Ancienne décharge », les ruisseaux du gros Pré et Mont Bonnet. La quatrième partie (Part IV) intitulée « Contamination métallique des sédiments du site de la décharge d’Étueffont », aborde l’étude de la variation spatiotemporelle des éléments traces métalliques au niveau des lixiviats et des sédiments dans les quatre lagunes du site de la décharge d’Étueffont. Afin de déterminer le degré de contamination métallique des lixiviats et des sédiments, nous avons procédé à un suivi de certains éléments localisés en amont, au milieu et en aval de chaque lagune avec un pas d’échantillonnage trimestriel entre octobre 2013 et avril 2016. La cinquième partie (Part V), complémentaire du chapitre précédent, définit plus précisément la distribution spatiale du panache à travers l’analyse de la qualité de l’eau souterraine au moyen de piézomètres. La sixième partie (Part VI) concerne les effets des métaux lourds sur les échanges gazeux et la fluorescence des chlorophylles chez (Typha latifolia). Le septième chapitre (Part VII) est consacré à l’étude des microorganismes de la décharge d’Etueffont : apport de la cytométrie en flux. Dans le huitième chapitre (Part VIII), nous aborderons l’étude de la bioaccumulation des éléments traces métalliques dans le Chironome Chironomus riparius. La dernière partie (Part IX) intitulée « Étude de la bioaccumulation des éléments traces métalliques au niveau des différents organes du gardon Rutilus rutilus», aborde l’étude de la bioaccumulation des éléments traces métalliques au niveau de différents organes (muscle, foie, arêtes et branchies). / The objective of this thesis work is to estimate the contamination level in the various compartments of the Étueffont discharge site namely: leachates, sediments, groundwater, fishes and insects. The microorganisms (< 10 µm) of the Étueffont discharge of were investigated at the single cell level by flow cytometry. This research work is structured in nine chapters.The first part (Part I), is dedicated to a literature review. Part II presents the study site, the storage of non-hazardous waste (ISDND) at Étueffont. Part III is dedicated to the analysis of leachate quality in lagoons, NC, SC, AD, MB and GP. Part IV addresses "Metal Sediment Contamination of Étueffont discharge site" It concerns the study of spatial and temporal variation of trace metals in leachate and sediment in the four lagoons landfill site of Étueffont. To determine the metal contamination level in leachate and sediment, we conducted follow-elements located upstream, middle and downstream in each lagoon with quarterly sampling between October 2013 and April 2016. Part V complements the previous chapter, by specifically defining the spatial distribution of the plume through the quality analysis of the piezometer groundwater. Part VI addresses the heavy metals impacts on gas exchange and chlorophyll fluorescence in (Typha latifolia). Part VII is dedicated to the microorganisms (<10 µm) investigation in the Étueffont discharge: by using flow cytometry. In the (Part VIII), we addressed the study of bioaccumulation of trace metallic elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd and Pb) in insect Chironomus riparius. Part IX entitled "Study bioaccumulation of trace metals in the various organs of roach Rutilus rutilus" concerns bioaccumulation of trace metals in different organs (muscle, liver, bones and gills) of this fish.
8

Hybridizace orobinců Typha latifolia a T. angustifolia / Hybridization of cattails Typha latifolia and T. angustifolia

Mašterová, Helena January 2013 (has links)
This study investigates the hybridization of two species of cattails, Typha latifolia (Common Cattail) and T. angustifolia (Narrow-leaved Cattail) in the Czech Republic. The aim of this study was to determine, how often T. latifolia and T. angustifolia hybridize, whether hybridization is allowed by overlapping flowering time of these species and whether it is possible these species controlled cross in a culture. For detection of hybrid individuals were used microsatellite DNA markers, which allow to detect hybridization events and differentiate hybrids from the parental species. Molecular analysis revealed that hybridization of T. latifolia and T. angustifolia occurs in the Czech Republic, but it is not frequent. Of the 267 analyzed individuals, 130 individuals were pure species T. latifolia, 108 individuals pure species T. angustifolia and 29 individuals were hybrids. Of the hybrids, 23 were advanced hybrids, 5 were backcrosses and only one individual was F1 hybrid. Flowering time of T. latifolia and T. angustifolia overlaps, which allows hybridization, and flowering time to not act as a prezygotic reproductive isolation barrier and gametes T. latifolia and T. angustifolia can blend together. In controlled crosses the female spikes T. latifolia and T. angustifolia created seeds, but these were...
9

Dygnsvariation av metanemission från en anlagd våtmark / Diurnal patterns of methane emission from a constructed wetland

Heiberg, Lisa January 2000 (has links)
<p>The aim of the study was to investigate if methane emission in a constructed wetland changed in a diurnal pattern correlating to temperature, humidity or light conditions. The gas measurements were carried out with a static chamber technique. The wetland (in Nykvarn outside of Linköping, Sweden) takes care of wastewater to reduce the nitrogen loads. Measurements were carried out at three different occasions in the summer of 1998 on two sites in the wetland. One site was close to the inflow, inhabited by Lemnaceae, and another site was located further downstream inhabited by the emergent macrophyte Typha latifolia. The results showed a variation, but no discernible diurnal pattern. The Typha site had a methane emission rate of 166 mg CH<sub>4</sub> m-2d-1 and the Lemnaceae site had an methane emission rate of 712 mg CH<sub>4</sub> m-2d-1. In all experiments at the Typha site, the highest methane emission rate was obtained at sunrise.</p>
10

Dygnsvariation av metanemission från en anlagd våtmark / Diurnal patterns of methane emission from a constructed wetland

Heiberg, Lisa January 2000 (has links)
The aim of the study was to investigate if methane emission in a constructed wetland changed in a diurnal pattern correlating to temperature, humidity or light conditions. The gas measurements were carried out with a static chamber technique. The wetland (in Nykvarn outside of Linköping, Sweden) takes care of wastewater to reduce the nitrogen loads. Measurements were carried out at three different occasions in the summer of 1998 on two sites in the wetland. One site was close to the inflow, inhabited by Lemnaceae, and another site was located further downstream inhabited by the emergent macrophyte Typha latifolia. The results showed a variation, but no discernible diurnal pattern. The Typha site had a methane emission rate of 166 mg CH4 m-2d-1 and the Lemnaceae site had an methane emission rate of 712 mg CH4 m-2d-1. In all experiments at the Typha site, the highest methane emission rate was obtained at sunrise.

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