Acta Facultatis Ecologiae - Technická univerzita vo Zvolene

154and higher concentrations of Zn, (Cd), As in deadbranches. As and Sb concentrations were possibleto compare in Picea abies (tab. 3).Higher As concentrations were in living branches(0.59 vs. 0.19 ppm). Sb concentrations were equalin living and dead branches (0.12 ppm). Betula pendulafrom the reference site (tab. 4) showed higherconcentrations of Ni, Co and Sb in living branches.Increased concentrations of Fe, Cu, Zn, Pb, Ag, Cd,Co and As were in dead branches. Quercus petraea(tab. 4) showed higher Co concentrations in livingbranches and higher concentrations of Fe, Cu, Zn,Pb, Ag, Cd, Ni, Co, As and Sb in dead branches.Plant tissuesPlants at the mine waste dumps have lack oforganic nutrients and moisture besides higher concentrationsof heavy metals. They mainly populatedepressions or weathered parts of the dumps. Permanentplants prevail at the old mine waste dumps.Annual and biennial plants are rare. Year shoots inliving branches of Pinus sylvestris from the dump--field are narrow (Fig. 3). Anomalous thin-walledtracheides (weak summer wood) were determined inseveral year shoots from 1994–1999. It shows thatsecondary coarsening of cell-wall did not pass offand bond between secondary cell-walls of tracheidesof reaction wood weakened and exfoliation of summertracheide cell-wall layers (fig. 4) was described.Lack of moisture (mostly in summer) is probablythe main reason of this state besides contaminationof tissues by heavy metals. It is probably thereason of insufficient soil-forming at the dumps.Formation of pressure reaction wood was determinedin tissues from 1995–2007 (Fig. 5). Formationof very narrow year shoots has been observed inFig. 3 Comparison of the current year shoots in analysed samples of the Pinus sylvestris.Dump-field – sample LB-103: 1 – living branches. 2 – dead branches; Reference site – sample LB–101: 3 – livingbranches. 4 – dead branchesdead branches of Pinus sylvestris from the dump--field over the last 13 years (Fig. 3). Occurrence ofnumerous calluses with near formation of numerousresin canals was confirmed. Cell-wall coarseningof the summer tracheides is completely missingin the last year shoots. Tracheides of reactionwood in live branches from the reference site arerelatively regular.In some samples of Betula pendula is visiblezonal occurrence of thick-walled fibres (Fig. 7).Exfoliation of secondary cell-wall of summer tracheidesis possible to observe in the cross-section.This trend weakened in 1999–2000. Marks ofweaken cohesion of secondary cell-wall and its exfoliationextreme narrow year shoots are possibleto observe in the cross-section of dead branches.Fig. 4 The living branches of the Pinus sylvestris fromthe reference site: exfoliation of summer tracheidecell-wall layers