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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

Ecological conditions limiting the distribution of 'Fagus silvatica' L. and 'Abies alba' Mill. near Schwarzenberg (Lucerne) Switzerland /

Gadekar, Hirasa. January 1975 (has links)
Diss. Nr. 5408 Naturwiss. ETH Zürich. / SA aus: Veröffentlichungen des Geobotanischen Institut ETH, Stiftung Rübel, Band 541975.
2

Změny jadérka v průběhu buněčné smrti

Juráň, Stanislav January 2013 (has links)
No description available.
3

Monitoring zdravotního stavu semenáčků a sazenic v Lesní školce Pasa Hejtmánkovice

Králová, Eliška January 2011 (has links)
No description available.
4

Testování účinnosti chuťových repelentů pro ochranu zakládaných výsadeb lesních dřevin před okusem zvěří / Evaluation of taste repellents for protection of tree planting stock from deer browsing

Triner, Libor January 2016 (has links)
The main goal of this thesis is to assess the efficacy of two repellent products with active ingredients denatonium benzoate and capsaicin to protect the newly established forest tree planting prior to browsing damage by wild game. Repellents were tested on two different experimental plots planted with silver fir (Abies alba). Application of repellents held in three terms and total three times were the damages, which were included in the framework of the six-rating scale, has been detected. The effectiveness of these repellents has been demonstrated already during the second term damage assessments caused by game. During the more than 14-month experiment was damaged almost 2.5 times fewer seedlings treated with repellents based on denatonium benzoate and capsaicin than untreated seedlings, serving as a control. The most common form of damage to the tree was bitten off terminal bud with little scope of additional damage. Damage to seedlings by game differed significantly even within the investigated areas. Use of repellents did not affect the physiological death of seedlings. It was justify the conclusion that most of the damages were caused by roe deer (Capreolus capreolus). Based on several scientific papers on the efficacy of repellent products based on capsaicin and denatonium benzoate was concluded that the main active ingredient in tested repellents is capsaicin.
5

Improving the methods for cryopreservation of endangered conifers

Gaiduschová, Daniela January 2016 (has links)
Preservation of plant genetic material is essential for any biological field. Compared to serial in vitro sub-culturing, cryopreservation often represents optimal long-term conservation technique. The crucial factors influencing successful cryopreservation include 1) proper pre-treatment, 2) cryoprotectants, 3) adequate freezing pace and 4) cold-hardening. Finding the appropriate method for cryopreservation of each species is the ultimate goal of research in this field. This work is focused on finding the optimal protocol for cryopreservation of embryogenic cell masses of coniferous species bog pine (Pinus uncinata subsp. uliginosa) and optimizing the existing one for European silver fir (Abies alba), both endangered in the Czech countryside. Cryopreservation design compares effectivity of different pre-treatments and cryoprotectants, determines the role of cold-acclimation step and evaluates resistance of selected conifer cell lines to freezing and desiccation. Post-thaw recovery of Bog pine cell line BE4 was better than cell line BR1, where no living cells were visible using FDA/PI staining. Proliferation rate was higher for European silver fir than for bog pine, especially for cell line II-2-10. Cryoprotective mixture with DMSO (PGD I) proved to be more effective than the mixture with glycerol (PGG) in cryopreservation of European silver fir. PGD I also proved to be optimal cryoprotective mixture for bog pine. In both cases, 0.4M sucrose was used as a pre-treatment and cold-hardening was included.
6

Variabilité démographique et adaptation de la gestion aux changements climatiques en forêt de montagne : calibration par Calcul Bayésien Approché et projection avec le modèle Samsara2 / Demographic variability and adaptation of mountain forest management to climate change : calibration by Approximate Bayesian Computation and projection with the Samsara2 model

Lagarrigues, Guillaume 16 December 2016 (has links)
Les hêtraies-sapinières-pessières de montagne paraissent particulièrement menacées par le réchauffement climatique. Pour appréhender la dynamique future de ces forêts et adapter la sylviculture à ces nouvelles conditions, il est important de mieux connaître les facteurs environnementaux impactant la démographie de ces espèces. Nous avons abordé cette problématique en combinant des données historiques de gestion, le modèle de dynamique forestière Samsara2 et une méthode de calibration basée sur le Calcul Bayésien Approché. Nous avons ainsi pu étudier conjointement les différents processus démographiques dans ces forêts. Nos analyses montrent que la démographie forestière peut varier fortement entre les parcelles et que le climat n'est pas toujours déterminant pour expliquer ces variations. Ainsi, malgré les changements climatiques attendus, la gestion irrégulière pratiquée actuellement devrait permettre de maintenir les services rendus par les peuplements mélangés situés en conditions mésiques. / The spruce-fir-beech mountain forests could be particularly threatened by the global warming. To better understand the future dynamics of these forests and adapt the silviculture to these new conditions, a better knowledge of the environmental factors affecting the species demograhics is needed. We studied this issue by combining a historical management data set, the forest dynamics model Samsara2 and a calibration method based on Approximate Bayesian Computation. We were able thus to study jointly the different demographic process in these forests. Our analysis show that the forest demographics can strongly vary between stands and that climate is not always determining to explain these variations. The unven-aged management currently applied seem adapted for the mixed stands located in mesic conditions, but the pure spruce forests and the low elevation stands could be highly impacted.
7

Studium vlivu fytohormonů a ektomykorhizních hub při maturaci a konverzi somatických embryí jehličnanů

Filippova, Mariia January 2015 (has links)
This thesis deals with the exploration of the influence of various phytohormones, primarily the influence of abscisic acid on the process of maturation and the influence of auxin and gibberellin on the process of germination of two types of conifers, Abies alba and Picea abies, often used as a material in the discovery of somatic embryogenesis. Each genotype prefers specific concentration ABA. 15 uM and 45 uM is the most effective for the cell lines Abies alba; 15 uM and 30 uM ABA for Picea abies. Auxin (IBA) and gibberellin (GA3) did not support the growth of roots of Abies alba. The interaction between fungal cultures Paxillus involutus and Amanita muscaria and between the embryos during the germination was studied as well. Fungal culture Paxillus involutus had very fast speed of growth on the germination medium. Fungal culture Amanita muscaria was growing very slowly. The effect of fungi on the germination has not been observed.
8

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.
9

Přeměny smrkových porostů na majetku Dr. Kinského ve Žďáru nad Sázavou

Hromádko, Petr January 2009 (has links)
No description available.
10

Kartläggning över spridning av silvergran, Abies alba

Henriksson Larsson, Henny January 2021 (has links)
Silvergran, Abies alba, är en ursprungligen odlad art som har fått snabb spridning i södra och mellersta Sverige de senaste 100 åren. Risk finns att denna art är invasiv och kan påverka vår inhemska flora och fauna negativt. I ett lövskogsområde norr om Uppsala finns en ungefär 70 år gammal plantering av silvergran som är nära 1200 kvadratmeter stor. I området kring planteringen har ett stort antal plantor av silvergran etablerat sig och syftet med denna studie är att kartlägga spridningen av arten i området. Studien kan bidra till att skapa ett generellt spridningsmönster för silvergran i liknande miljöer i Sverige. Att kartlägga spridningsmönstret kan vara fördelaktigt både för att kunna avgöra om arten måste klassas som invasiv, och om åtgärder behöver vidtas mot den möjligt invasiva ädelgranen. Skogsområdet är omgivet av åkermark och har inventerats genom transekter indelade i rutor. Från inventeringen är en generell spridning av silvergran kartlagd för skogsområdet. Granarna uppmättes i olika storlekskategorier, vilket är representerat i de framställda kartorna. På så sätt får man direkt en visuell överblick över spridningen av silvergran i skogsområdet från ursprungskällan. Tydligt är att silvergranen har stor möjlighet att på egen hand sprida sig i den sydliga, svenska lövskogen och hur spridningen av silvergran i framtiden kommer se ut är ett ämne för diskussion och studier.

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