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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.
21

Vliv managementu na vybrané druhy mechů rašelinných luk (Breidleria pratensis, Sphagnum warnstorfii, Tomentypnum nitens) / Effect of management on three moss species of fen meadows (Breidleria pratensis, Sphagnum warnstorfii, Tomentypnum nitens)

VELEHRADSKÁ, Tereza January 2013 (has links)
Effects of different types of management (control, mown, mown + disturbed (gaps) + litter removed) on three moss species of fen meadows were studied. Experimental plots were established at sixteen sites in the Bohemian Forest, in the foothills of the Bohemian Forest and in Českomoravská vrchovina. Relevés and micromaps of bryophytes in the plots 0.5 × 0.5m were sampled at the beginning of the experiment during the summer season of 2010 and then after 3 seasons (during the summer season of 2012) of performing management. The age of the abandoned meadows was also determined and values of pH, conductivity and height of water level of each plot were measured. Positive influences of both types of management on the cover of Tomentypnum nitens and of management with creating gaps and remowing of litter on the cover of Breidleria pratensis were significant. Effect of management on the Sphagnum warnstorfii was significant only when processes of remaining on already occupied places and the expansion to new places were tested separately. Enviromental values did not significantly influence the change of cover of any species between 2010 and 2012. In conclusion, it is clear that diverse management with reasonable use of these practices (mowing, creation of gaps, litter removal) is desirable for maintaining of vital and diverse bryophyte layer.
22

Vliv různých způsobů obhospodařování na travní porosty / Effect of different management practices on grassland

SEJPKOVÁ, Jana January 2014 (has links)
The aim of this thesis is to assess the impact of farming on grassland and assess the frequency of use of grassland on yield and quality of forage biomass. A part of this thesis is also a recommendation of possible management changes of evaluated grasslands. Botanical inventory surveys were conducted on agricultural lands Bílovské zemědělské a.s., in the northern Plzeň region. There have been selected three sites, two meadows and one pasture vegetation. The comprehensive analysis of the stand composition was created by agrotechnology of meadows. An important part of this thesis is to assess the impact of different grassland management practices with regard to their economic, social and ecological importance.
23

Functional diversity and restoration of meadows in Northeast Ohio

Plevniak, Keri 21 June 2019 (has links)
No description available.
24

Žabovřeské louky / Žabovřesky Meadows

Markevičová, Vendula January 2010 (has links)
Žabovřeské and Komínské meadows are divided acording to their names, but in the real landscape it is just only fluent space of large river valley. The space was created by river fo ages, so I let the space to float with the river. All important division of the space are done in parallel with the river, that itself classife the calm, narrower and more familiar right bank and more open, larger left bank of the river. The river shaped the linear charakter of the park and in the same time identify the circle – the space of stop in. The superficies of the area: 141,1 ha.
25

An ecological investigation of spiders in coastal meadows : in Uppland and Sörmland

Langbak, Marie January 2022 (has links)
Coastal meadows are important habitats for many animals, but the habitats are threatened by changes in land use such as abandonment of grazing. On the Swedish East coast, many coastal meadows can be found and they are highly influenced by the brackish marine environment which supports large populations of spiders. Spiders are the most abundant carnivorous arthropods on coasts of Uppland, and it is known that spider communities are closely associated with the vegetation. This study aims to investigate the spider communities in coastal meadows in Uppland and Sörmland, Sweden, and spiders were collected with pitfall traps and vacuum suction sampling. The meadows are under varying management either grazed by cattle, abandoned or has never been managed, and this is expected to influence the vegetation structure. The vegetation was on average higher in the abandoned sites, but the coefficient of variation in height was similar. The Lycosid community was not influenced by the vegetation structure, but was extremely abundant. Mean height of the vegetation had a positive influence on species richness, and a higher number of species were found in the abandoned and grazed meadows compared to the non-managed meadows, in the analysis of the vacuum sampled community. The communities were distinctly different in meadows under different management, and this was influenced by the height of the vegetation. Management of costal meadows is therefore also important for conserving diverse communities of spiders, but clearly some spiders prefer the less species rich un-managed habitats, so consideration should be taken to this.
26

Pasture and meadow management

Burke, T. E. January 1922 (has links)
Master of Science
27

An Alternative Planting Treatment for Turf Open Spaces in Conservation Subdivisions

Krueger, Timothy William 27 April 2001 (has links)
As conservation subdivisions increase in popularity, large tracts of community open spaces are being created. The typical landscape treatment is usually reminiscent of the English Landscape School: acres of turf providing little wildlife habitat or environmental benefits. Many homeowners are sold on the idea of great expanses of turf similar to a golf course. The open spaces are generally left to the homeowners association to maintain. In some cases it is donated to local municipalities. Maintenance is often expensive and places a burden on local governments. This study will show that creating more sustainable open spaces can correct this problem. This can be accomplished through the use of an ecologically based planting design. The following thesis project focuses on an alternative landscape planting treatment for these large open spaces, a treatment that has a significant cost savings and offers a different experience. / Master of Landscape Architecture
28

Is All Open Space Created Equal? A Hedonic Application within a Data-Rich GIS Environment

Neumann, Bradley C. January 2005 (has links) (PDF)
No description available.
29

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.
30

Structure, Composition, and Emplacement History of Orbicular Granites and Comb Layering, Sierra and Sequoia National Forests, CA

Eisenberg, Jane L 01 January 2014 (has links)
Orbicular and comb layer textures in igneous environments are evidence of an unusual heating and cooling regime in small pockets at the edges of crystallizing magmas. Changes in the composition of a magma spark rapid changes in temperature, which cause the temporary suppression of normal crystal nucleation. As the superheated or supercooled magma returns to equilibrium temperature, crystallization occurs exclusively on pre-existing nucleation surfaces (floating xenoliths or wall rocks), creating orbicular and comb layering textures. Orbs and comb layers collected from two localities in the central Sierra Nevada Batholith were analyzed to determine 1) how they formed and 2) what their formation history reveals about the emplacement histories of their respective host plutons. Geochemical analysis including XRF, U-Pb dating and Sr-Nd and O isotope analysis was used to constrain the characteristics of the orbicular magma. Cathodoluminescence as well as macro and microscale petrography was used to determine the specific growth history of the orbs and comb layers. This study shows that orbs and comb layers from both localities formed due to superheating caused by the influx of water into the orbicular melt. Subsequent cooling was caused by mixing–induced depolymerization and fluid enrichment (Big Meadows Creek) or emplacement into a cooler host rock (Deer Creek). Both locations studied are 2–3 Ma younger than their host plutons, indicating that the processes which form orb and comb layers may cause late melting and magma remobilization in larger plutons.

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