Morphometric parameters of conifer needles and shoots in the areas near the Kunda cement plant
2000
Ots, K. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
To study the impact of air pollution on the growth of conifers sample plots were established at different distances and directions from the Kunda cement plant. The plots included stands of 70-80-year-old Scots pine and Norway spruce. Although emission of alkaline cement dust had decreased in the second half of the 1990s analyses of soil samples collected to characterise the growth substrate of trees showed that the pH value of the humus horizon of weakly podzolised temporarily overmoist sandy soils was within the radius of 3 km from the cement plant 2.0-2.9 times as high as that of the control plots in Lahemaa National Park. To ascertain the effect of alkaline environment on the growth of conifers the length (cm) of the needles and shoots formed in 1996-99, dry and wet mass (g) of 100 needles, dry matter content of needles(per cent) and density of needles on shoots were measured. The results obtained were compared with data from 1992 if possible. Both pine and spruce were found to be sensitive towards cement dust pollution and alkalised environment; however, the impact on different morphological parameters was different. As compared to the control, the strongest inhibition of growth was revealed in the sample plot situated 2.5 km east from the cement plant. Conifers on sample plots 2 km west from the emission source showed more vigorous growth than the control. As compared with data from 1992, some improvement in the growth of pine and spruce was observed
显示更多 [+] 显示较少 [-]