The influence of immission stress on height growth in spruce stands
2002
Brezina, L. | Sedmak, R. (Technicka Univ., Zvolen (Slovak Republic). Lesnicka Fakulta)
The paper is aimed at solving the problematics of identification and quantification of mean height increment changes in the stands situated in the region of extensive immission impact. The increment changes were derived from the comparison of actual mean stand heights determined during the creation of forest management plans (FMP) in 1995 with the modelled mean heights (determined during the creation of previous FMP in the year 1978) updated by model of actualization (FABRIKA 1998) for the time horizon of the year 1995 with reference to pollution-hazard zones (B-D) and age classes (6-9). The gained results have approved the expected assumption, that the values of differences actual and modelled mean heights have shown the ascending (improving) trend from the zone B to D and counterwise, in the direction of the 6 th age class they have followed descending (degrading) trend, though the test of coincidence of differences between the actual and modelled mean heights have shown the ascending (improving) trend from the zone B to D and counterwise, in the direction of the 6 th age class towards the 9 th class they have followed descending (degrading) trend, though the test of coincidence of differences between the actual and modelled mean heights demonstrated that in all but one case in the categorisation of pollution-hazard zones and age classes the differences did not differ statistically significantly
显示更多 [+] 显示较少 [-]