Naslov
30 Years of Research of Crown Development of Common Oak in Croatia

Autori
Krejči, Vlado ; Dubravac, Tomislav

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
International Conference Oak 2000 Improvement of Wood Quality and Genetic Diversity of Oaks / Vukelić, Joso ; Anić, Igor - Zagreb : Fakultet strojarstva i brodogradnje Sveučilišta u Zagrebu, 2000, 29-31

Skup
International Conference Oak 2000 Improvement of Wood Quality and Genetic Diversity of Oaks

Mjesto i datum
Zagreb, Hrvatska, 20.05.2000. - 25.05.2000

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
common oak (Quercus robur L.); crown; growth and development; Croatia

Sažetak
Tree crown is one of the most susceptible and most conspicuous indicators of physiological condition of forest stands and as such presents an interesting medium of monitoring and research, especially if the research aim is common oak, which is our most valuable tree species. Crown structure researches have a significant place within the research of ecological-management types of Croatian forests during the last thirty years. Issues related to that include the research of growth intensity and crown development in horizontal and vertical sense in relation to diameter at breast height and stand age, period of highest crown growth and the patterns that exist among them. Insight into patterns of crown growth is a significant factor in performing appropriate and timely management, both for the forest expert working in exploitation and the one working in silviculture in decision making process related to time, manner and intensity of silvicultural operations. Relations among tree crowns change in the course of development due to natural selection and silvicultural operations. By searching for the patterns among elements of crown structures, i.e. by establishing empirical equations, we search for answers to the following questions: what is the form and intensity of connections (correlations) among particular crown structure elements (diameter, length, area and crown volume) and diameter at breast height, since by the increase of d.b.h. these relations change, as well as the interrelationships of researched variables with other tree segments. Research of change patterns of width, length and area of crowns in relations to the corresponding increase of d.b.h is linear and the interdependence can be expressed by straight-line equation. Crown volumes by diameter degrees are of varying size and its pattern can be presented by curve-lined regression in the shape of exponential growth function. Crown form factor is 0,56, relative development of crown length is 45% of tree height and relative development of crown width (relation between d.b.h. and crown diameter) is 17 times, on an average. The increment of crown width of mean stand tree achieves its maximum amount of 15,69 cm at d.b.h. of 8 cm, 17 years of age, and ground crown cover of 70% is a good precondition for natural regeneration. Interception is the highest in medium-aged (21,9%) stands, and the lowest (2,3%) in young stands, while the precipitation conflux down the trunk, per 1 m2 of crown area of young trees is 23,9 times bigger than that of mature trees. Research results will be used for monitoring systematic dynamics of growth and development of crowns with the aim of preserving permanent self-regenerability of common oak stands.

Izvorni jezik
Engleski

Znanstvena područja
Biotehnologija

POVEZANOST RADA