Giant Mts Research Articles

Foliation of spruce in the Giant Mts. and its coherence with growth and climate over the last 100 years

Les variations du feuillage de cinq sapins (Picea abies [ L. ] Karst.) provenant des Monts Kroknose en Republique Tcheque, ont ete etudiees sur une periode couvrant les 100 dernieres annees afin d'etablir une possible relation existant entre la croissance et le climat. Le feuillage a ete evalue d'apres les traces laissees par les aiguilles dans le tronc principal. La production moyenne annuelle d'aiguilles de 355 aiguilles par pousse, qui est correlee avec la longueur annuelle de pousse, a ete affectee par les temperatures prevalant en mars et octobre de l'annee precedente. Le resultat d'une determination de la production d'aiguille basee sur l'etendue de la periode de vegetation est discutee. La retention d'aiguilles sur les arbres s'eleve en moyenne a 6,5 aiguilles par pousse ancienne mais les variations a long terme sont considerables. L'âge maximum des aiguilles atteint 9,8 ans. La perte annuelle en aiguilles est comprise, par an, entre 0,1 et 2,3 aiguilles par pousse ancienne. Aucune relation n'a ete etablie entre la perte annuelle en aiguilles d'une part, et l'augmentation radiale ou la croissance des pousses d'autre part. La retention et la perte annuelle en aiguilles sont ici independantes du climat.

Atmospheric deposition levels of chosen elements in the Czech Republic determined in the framework of the International Bryomonitoring Program 1995

In order to determine the atmospheric loads of 13 elements (Al, As, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb, S, V, Zn), samples of Pleurozium schreberi (81.1%), Hypnum cupressiforme (11.2%) and Pseudoscleropodium purum (7.7%) bryophytes (mosses) were taken and analysed from an approx. 20×20-km grid extending over the entire territory (78 864 km 2) of the Czech Republic (abbreviated `the CZ' in this study). The level of the elements found in the bryophytes reflects the relative atmospheric deposition loads of the elements at the investigated sites. Five hot spots indicating relatively high deposition levels were identified in the CZ. The marginal hot spots are the following: the CZ part of the so-called Black Triangle I territory in northwestern CZ; the CZ part of the Black Triangle II territory in northeastern CZ; and the CZ part of the Sudeten mountains (Jizerské Mts and Giant Mts) and their foothills in northern CZ. Inland hot spots were found in the southwestern industrial part of central Bohemia and in the southern Moravian industrial district. The average element contents in CZ bryophytes were comparable with the respective average values obtained in Germany and Poland. However, the CZ average bryophyte values were higher and lower in comparison to the average Austrian and Slovak values, respectively. The CZ average relative atmospheric deposition loads of the elements were found to be 2–3 times higher than the respective loads in the cleanest parts of Europe (e.g. clean parts of Nordic countries). A comparison of the analytical results obtained repeatedly at 20 identical localities in the CZ showed a significant decrease in the relative deposition loads of all of the investigated elements in 1995 as compared to 1991. This decrease has been caused by the dramatic restriction of the industrial production, mainly that of the metallurgical and chemical industries, in the CZ. Desulphurisation programs and the effective trapping of flying dust particles in CZ power plants has also had a positive influence on the deposition climate in the CZ. The average values for the absolute atmospheric deposition of the investigated elements in the CZ in 1994–1995 as found from bryomonitoring are presented in this paper.

Reconstruction of Air Temperature of the Summer Half-year in Krkonoše (Giant Mountains) Based on the Spruce Tree-rings in the Period 1804 - 1989

The tree-ring width and the maximum wood density of Norway spruce (Picea abies (L.) Karst.) have been examined in order to reconstruct air temperature of the summer half-year during the period 1804 - 1989. The trees examined come from a natural spruce stand of Labský důl (Elbe Valley) in Krkonoše (Giant Mts.), North Bohemia. The results obtained by this way have been compared with a similar reconstruction made for Central Europe and with air temperature records from the Prague-Klementinum station. Both temperature series (reconstructed and measured), however, show only 36 % of commonly clarified variability. Differences may follow from the standardization of dendrochronologies as well as from other factors which may have influenced the growth of spruce. The quality of air temperature measurement may play also role.

Flood on the Jizera in August 1978

The authors analyse precipitation and runoff in the drainage basin of the upper and middle Jizera during the great flood, August 8-10, 1978, caused by extraordinary intensive precipitation in the area of the Jizerské hory (Mts.) and the western Krkonoše (Giant Mts.). The flood caused changes in river beds and on flood-plains and much damage for the national economy.