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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.
131

Bryophytes on boulders : diversity, habitat preferences and conservation aspects /

Weibull, Henrik, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
132

Genetics of virulence and intraspecific interactions in Heterobasidion annosum s.l. /

Lind, Mårten, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.
133

Thinning of Norway spruce /

Wallentin, Cristofer, January 2007 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniversitet, 2007. / Härtill 4 uppsatser.
134

Impact of elevated temperature and [CO₂] on spring phenology and photosynthetic recovery of boreal Norway spruce /

Slaney, Michelle, January 2006 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
135

Impregnation of Norway spruce (Picea abies L. Karst.) wood with hydrophobic oil /

Ulvcrona, Thomas, January 2006 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2006. / Härtill 5 uppsatser.
136

Lignin studies of transgenic Norway spruce /

Wadenbäck, Johan, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2006. / Härtill 4 uppsatser.
137

Tillväxtökning vid fastgödsling av granungskog / Growth increase in fertilization of young norway spruce stands

Verner, Jörgen, Karlsson, Mårten January 2018 (has links)
Swedish forest takes up and stores 60 million tons of CO2 every year. Which is a great climate benefit. Fertilization of forest results in a growth increase beacuse of the added nutrients supplied to the trees. This leads to an increased amount of needles that can produce a higher photosynthesis. The purpose of this report has been to examine the possibility of growth increase of norway spruce (Picea abies) with frequency fertilization in young stands. Earlier studies have shown that this is an efficient way to increase the stemwood production. The study has one hypothes, the growth increase in frequency fertilized young stands results in a yearly growth increase of 10 m3 per hectare compared to unfertilized stands. The material of this study is prepared from assessments from trials in Tranemo and Toftaholm in southern Sweden. The results have been compared to data from earlier assessments in the trial stands. Tranemo and Toftaholm is fertilized six times since 2003. The fertilizer dose is optimized after a needle analysis before every fertilizing occasion. The results show that the volume, diameter, basal area and individual stem volume is higher in the fertilized areas than in the unfertilized areas for both Toftaholm and Tranemo. The growth increase at the fertilized areas has increased significant compared with the unfertilized areas. The growth increase at the fertilized areas is 24-25m3 per hectare and year. The growth increase at the unfertilized areas is about 15m3 per hectare and year. Fertilization of young stands results in a high growth and shortens the rotation period considerably, the trees reach higher dimensions in shorter time. This study indicates that the number of stems per hectare has an impact on the growth increase in fertilized stands.
138

Dynamika růstu výsadeb jedle bělokoré v závislosti na nadmořské výšce a expozici v Krkonošském národním parku / Silver fir growth depending on altitude and slope exposition in National park Krkonoše

Zapadlo, Jan January 2016 (has links)
This Master thesis deals with a dynamic of planting development of silver fir (Abies Alba Mill.) depending on an altitude and exposure in the mountain conditions of the western part of the Krkonose (Giant Mountain) National Park. Further it examines the influence of a tree age, average temperature and precipitation amounts on such a development. Annual silver fir height increments have been compared on the four selected sites which differ from each other, in particular, by their altitude but other characteristics have been considered as well. Analyses proved that there were significant statistical differences between an average height increments on these sites. Through the methods of correlation and regression analyses impacts of other factors on the said differences along with the intensity of such impacts have been identified. In addition to the altitude a factor of an average temperature, precipitation amount during a given period and a tree age have been determined. Whilst examining the dependency of fir development using more factors simultaneously a linear regression model of dependency between the fir height increments and joint effects of the aforementioned factors has been created.
139

Dynamika horského smrkového lesa se zaměřením na vývoj přirozené obnovy / Dynamics of mountain spruce forest focused on natural regenaration development

Červenka, Jaroslav January 2016 (has links)
Disturbances have a major impact on the dynamic of forest ecosystems. However, there is lack of its exact consequences for mountain spruce forests in Central Europe. In 2007 heavy windstorm damaged a lot of stands in Šumava NP, subsequent bark beetle outbreak resulted in a large-scale dieback of spruce stands in this area. We took advantage of this opportunity. This study is focused on disintegration and structure of stands after the severe disturbance and in next step is focused on density and structure of natural regeneration in these stands. In addition we dealt with spruce regeneration (Picea Abies (L.) Karst.) on decaying logs. We compared two localities, disturbed (NP Šumava) and undisturbed site (CHKO Jeseníky). We concentrated on the change in saplings densities and on impact of decaying logs characteristic on this change. Finally we wanted to determinate impact of decaying logs characteristic on density of spruce regeneration. In area of Trojmezná we recorded 99 % mortality of parent stands. We founded only a few of adult tress which survived the disturbance, in addition we found several new trees, most of them with diameter about 10 cm. Live trees (DBH > 7 cm) reach density 16 trees per ha. The amount of dead wood was 2.5 times higher than before 10 years, one third were lying logs. Only natural regeneration of Norway spruce and rowan (Sorbus acuparia L.) was founded. Regeneration recruitments occurred in sufficient numbers, mostly on mosses (32 %), dead wood (27 %) and the nearest neighbourhoods of living mature trees or snags (28 %). Advance regeneration occupied 88 % of all regeneration. The density of individuals was similar along the elevation gradient. But in lower elevation of study area was situated higher regeneration recruitment then in the higher parts. With increasing elevation gradient regeneration was more homogenous in height and was lower. Best conditions for spruce regeneration provides logs with the largest diameters and logs with presence of white fungi Armillaria spp. or Phellinus nigrolimitatus. On the other hand logs with presence of Fomitopsis pinicola do not provide a suitable microsite for saplings. When we compare change in regeneration density on dead wood between the disturbed and undisturbed site, our results show significant increase in regeneration density at disturbed site (by 33 %). The increased regeneration density observed at the disturbed site was mostly associated with the smallest saplings on logs with the largest diameters. Three years after death of the parent stands no significant effect was recorded on the growth rate and survival of established spruce saplings on dead wood.
140

Růst a environmentalní vlivy pěstovaní jedle obrovské v podmínkách České republiky / Growth and environmental effects of Grand fir cultivation in conditions of the Czech republic

Fulín, Martin January 2016 (has links)
Grand fir (Abies grandis /Douglas ex D. Don/ Lindl.) is a species with potential benefits for the implementation of many functions in forest management: namely the function of production, soil improvement, stabilization and landscaping. It was introduced to the Czech Republic, as well as to other European countries, since the first half of the 19th century, mainly by aristocratic families. First plantings were performed in the parks, but gradually also in the forest stands. Another wave of interest in this tree species was associated with the decline of the domestic silver fir (Abies alba Mill.). It was to some extent substitute, for this period comes the greatest number of plantations in the country. The aim of this thesis is, therefore, monitoring of growth and production of the grand fir, but also the evaluation of the effects on the basic characteristics of the soil chemistry, nutrient dynamics and possible degradation effect on forest lands. Research areas were mainly located in the University Forest Enterprise Kostelec nad Černými lesy, but also in other places such as Hrubá Skála at Turnov, forests owned by Kinský at Žďár nad Sázavou and Kynšperk nad Ohří. Monitoring was carried out on already established and monitored middle-aged permanent plots (35 to 55 years), which were assessed at mensurational parameters (position, height, diameter at breast height, ratio of the green crown), in further the quantity and quality of forest floor and upper mineral soil components was studied. This work also contains the measurements of the provenance plot of Forestry and Game Management Research Institute. The results show that the grand fir is a productive tree species that exceeds the stock of domestic conifer tree species and its intensive growth is comparable with Douglas fir. From the perspective of provenance trials is crucial the correct choice of provenance, which achieves better yields and quality of wood. Best provenances come from the island Vancouver and the coast of Washington state. At the soil analysis reaching grand fir better values in comparison with Norway spruce and got it closer to the values of broad-leaved tree species. Thus it can be said that grand fir represents important soil-improving and stabilization tree species.

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