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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

Soil and vegetation characteristics of montane and subalpine wet meadows, Sierra Nevada, California

Olsen, Hayley R. January 2009 (has links)
Thesis (M.S.)--University of Wyoming, 2009. / Title from PDF title page (viewed on June 16, 2010). Includes bibliographical references.
2

Bird communities and vegetation on Swedish wet meadows : importance of management regimes and landscape composition /

Gustafson, Tomas. Berg, Åke. January 2006 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2006. / Errata sheet inserted. Appendix includes reproductions of papers and manuscripts co-authored with Åke Berg. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix of papers.
3

Changes of the vegetation of wet meadows depending on management / Changes of the vegetation of wet meadows depending on management

HORNÍK, Jan January 2015 (has links)
Central Europe wet meadows are characterized by considerable species richness. The biodiversity maintenance of the wet meadows is connected with regular management (i.e. grazing or mowing). As their area drastically decreased due to changes in land use in the last century, they have become the object of interest among scientists, conservation biologists. This thesis is composed of three original studies which are focused on escribing diversity patterns of the whole spectra of wet meadows at landscape level and dynamic of their changes depending on different management regimes (mowing/abandonment,fertilizing/unfertilizing). The synthesis of these studies reveals the description of the processes underlying the wet meadows species loss depending on land use changes and proposes the principles for sustainable conservation management.
4

Dekompozice nadzemní biomasy travinného mokřadního porostu / Decomposition of aboveground biomass of a herbaceous wetland stand

KLIMOVIČOVÁ, Lucie January 2012 (has links)
The master?s thesis is part of the project GA ČR č. P504/11/1151- Role of plants in the greenhouse gas budget of a sedge fen. This thesis deals with the decomposition of aboveground vegetation in a herbaceous wetland. The decomposition rate was established on the flooded part of the Wet Meadows near Třeboň. The rate of the decomposition processes was evaluated using the litter-bag method. Mesh bags filled with dry plant matter were located in the vicinity of the automatic meteorological station at four randomly selected sites. Values of the decomposition rate were assessed in two experiments. In the first experiment the litter bags were fixed in April 2009. The litter bags were fixed in the vertical position and they had one size. Values of the decomposition rate were assessed for 6 sampling dates and the total exposure time was 2,5 years. The decrease of the total dry mass was 18,37 % in the first year and 13,05 % in the second year. The value of LDR was 0,7227 in the first year and 0,4740 in the second year. In the 2nd experiment the litter bags were fixed in November 2010. The litter bags were fixed in the vertical and horizontal position, respectively, and they were of two sizes (small, big). Values of the decomposition rate were assessed for 2 sampling dates and the total exposure time was one year. The total annual value of LDR was 0,5212 for the vertical bags and 1,0676 for horizontal bags.
5

Ptáci řádu Passeriformes otevřené krajiny v CHKO Třeboňsko / Birds of Passeriformes order on CHKO Třeboňsko champaign

FUKA, David January 2008 (has links)
During the breeding season in 2007, the mapping of the nesting ranges in birds of the order Passeriformes was carried out on the chosen localities in Třeboň wet meadows within the Třeboňsko landscape; Aim of study was to order qualitatives and quantitatives status of the Passeriformes within localities and their comparasion. Localities were situated in the immediate vicinity of Třeboň. The total mapped area was 25 hectares. The Vegetation was dominated by tall sedges (locality New station). The principal biotops consisted of tall sedges biotop M1.7 and K1 (locality New station and locality Old station) and V1 biotop. Within Old station locality and Opatovický locality it was especially: T1.5 and T1.4 and X5. Nesting birds were counted by the mapping method (Janda a Řepa, 1989). The GPS system was used for the recording of single males. Twenty three passerine bird species were found within localities. In total, nine bird species were founded in all the localities. The most abundant species were: (Acrocephalus schoenobaenus) the Sedge Warbler, (Luscinia svecica cyanecula) the Bluethroat, (Locustella naevia) the Grasshopper Warbler (Old station locality and New station locality), Opatovický locality was dominated by Acrocephalus schoenobaenus the Sedge Warbler. There was signigicant differences of total density of bird assemblage betwen Opatovický locality and New station locality and Old station locality and Opatovický locality. High breeding density was found especially in the Whinchat and the Bluethroat on New station locality. High conformity of bird assemblage was among New station locality and Old station locality.
6

Nadzemní produkce porostu zaplavované louky s dominantní ostřicí štíhlou (Carex acuta) / Aboveground production of a wet meadow stand dominated by Carex acuta

KUNCOVÁ, Štěpánka January 2009 (has links)
The MSc thesis is part of the project of Ministry of Environment of the Czech Republic entitled Czech Terra, which aims at assessing the carbon budget and cycle in the main types of ecosystems in the Czech Republic. This thesis is focussed on the production of aboveground biomass of Carex acuta, which dominates the unmanaged and permanently flooded part of the Wet Meadows. The seasonal dynamics of aboveground plant production was followed using a series of 9 destructive harvests during the vegetation season. On each date, four 0.5x0.5m2 samples were taken from the wetter, and four samples from the drier part of the stand. The maximum value of live biomass of C. acuta (550.8 g.m-2) was recorded on 13.6 2008. The highest value of live biomass of all species reached 602.4 g.m-2. The maximum total biomass (without litter) reached 994.6 g. m-2. The highest value of productivity of C. acuta (12.46 g.m-2.day-1) was recorded on 24. 5.
7

Effects of two-year nutrient loading on microbial community and N transformations in mineral and organic soils of wet meadows / Effects of two-year nutrient loading on microbial community and N transformations in mineral and organic soils of wet meadows

MACH, Jiří January 2010 (has links)
This study observes an influence of two-year application of NPK fertilizer on the amount of soluble nitrogen, microbial N transformations, and microbial biomass and the composition of microbial community in mineral and organic soils of two wet meadows. This study is the first version of manuscript, supplemented with a wider literature review, which will be submitted in 2010.
8

Vliv dostupnosti minerálních živin a zaplavení na růst ostřice štíhlé v nádobovém pokuse. / Effect of mineral nutrient availability and flooding on the growth of Carex acuta in a mesocosm experiment

SYCHROVÁ, Jana January 2011 (has links)
This MSc thesis is part of the project GACR 526/09/1545 Importance of newly assimilated carbon for the plant-soil interactions in wet grassland ecosystems in varying environmental conditions, which focuses on the effects of eutrophication on selected wet meadows with mineral or organic soil in the Trebon Biosphere Reserve. The results of this project will serve as a basis for developing a suitable ecosystem management for wet meadows, especially for sites registered as nature reserves. Pot experiments were carried out with Carex acuta, a dominant species of wet meadows that has already been subject of many studies. The aim of this work was to find out how C. acuta responds to different levels of fertilization and soil flooding under controlled conditions. The growth of the generative shoots of C. acuta was significantly affected by fertilization. The growth of vegetative shoots was significantly influenced by the soil organic matter content and fertilizer addition. The vegetative shoots reached greater length than the generative shoots. The pot experiment indicates that fertilization has not a large influence on the growth of C. acuta. This finding may explain field observations that C. acuta is gradually replaced in eutrophic habitats by stronger competitors, especially Phalaris arundinacea.
9

Effects of Grazing of Reed Canarygrass (Phalaris arundinacea) in Restored Wet Meadows in the Northern Tall Grass Prairie

Cleys, Jake Robert January 2019 (has links)
Reed canarygrass (Phalaris arundinacea) is a grass species that can dominate wet meadow plant communities. This study investigated if grazing by cattle on restored wet meadows suppresses reed canarygrass, thereby promoting the restored plant community. This study was conducted at two locations in northwest Minnesota. Management practices used were a patch-burn grazing treatment and a four-pasture high intensity-short duration grazing rotation. A pretreatment survey was conducted before grazing followed by annual surveys every five years after grazing. Both treatments reduced reed canarygrass canopy cover by 49 percent compared to non-grazed control sites. Grazed patches were moving towards a Carex dominated community. The community not invaded with reed canarygrass had similar native species richness at the end of the experiment in the rotational grazing treatment, and improved plant richness in the patch-burn grazing treatment. This study demonstrates grazing reduces cover of reed canarygrass, while maintaining or increasing native plant species richness.
10

Podmínky ovlivňující tvorbu rašeliny v kontextu obnovy rašelinných luk / Peat formation and peat meadow restoration

Krejčová, Jana January 2019 (has links)
This work aims to clarify and describe the necessary conditions of the peat soil horizon formation. The following three types of locations were compared. Drained locations that were revitalized afterwards. Locations which were drained and never revitalized. And lastly undrained localities where the original peat horizons are still presented. It has been proven that the grounwater level differs in drained and undrained areas. However, there was no significant differrence between revitalized and non-revitalized areas in drained types of locations. The results confirmed that Sphagnum spp., which is the most important species in peat formation, dominates the plant community where the groundwater level is higher than 25 cm. If the grounwater level is lower than 25 cm below the surface, Sphagnum spp. disappears very quickly and degrades peat soil horizons. The work also proved the groundwater level directly affects plant comunities that more or less promote carbon accumulation in the soil but water level and anaerobic conditions have no direct affect on soil carbon accumulation and only affect the vegetation composition of the peat soil horizon.

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