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The effect of mountain relief and industrial air pollution on biometric parameters of pine stands was studied. The empirical–statistical models of the dependence of biometric characteristics on the parameters of forest sites were developed using raster modeling and multivariate analysis. The possibility of predicting changes in the biometric parameters at any site on the basis of these models is shown.  相似文献   
2.
Manifestations of the edge effect on Scots pine (Pinus sylvestris L.) trees and stands were evaluated in natural southern taiga forests growing in a large industrial city (Yekaterinburg, Russia). For this purpose, 14 transects were laid out, each consisting of 6–10 circular 400-m2 plots arranged in a line that extended for 140–260 m into the tree stand, perpendicular to its boundary. During transect surveys, 128 records were made of parameters characterizing the state of pine trees (height, diameter, defoliation level, needle age) and stands (density and timber volume). The boundaries differed in age, i.e., the time of formation (no more than 8 years and more than 20 years ago), and type (adjoining to motorways or wastelands). The edge effect manifested itself only near old boundaries and only for tree height (5 m lower near the boundary than deep in the forest) and for stand density and timber volume (25% lower), independently of the boundary type. Since the test parameters linearly increased with distance from the boundary, it was impossible to estimate the range of the edge effect.  相似文献   
3.
The effect of increased ambient temperature on the vertical, radial, and volume increments of Scots pine (Pinus sylvestris L.) trees has been studied in the zone of thermal impact from a burning petroleum gas flare. Regular age-dependent changes in the pattern of increment dependence on the distance from the flare and ambient temperature have been revealed. The mechanisms of these changes are explained. It is concluded that an increase in ambient temperature by 1.0–1.5° C has a favorable effect on the dynamics of Scots pine growth.  相似文献   
4.
Morphometric characteristics of the growth of forest stands located at different distances from a large copper-smelting plant were estimated. The set of diagnostic parameters obtained was used for calculating summary parameters of the state (SPSs) of the forest stands and to grade their values for zoning the forests. The results of using semivariance analysis demonstrated the appropriateness of kriging, a method of spatial interpolation, for mapping the surfaces of the state of forests. The map-scheme of the zones differing in the state of forest stands (made on the basis of summary parameters) was compared with the topographic map of the area, which made it possible to estimate the effect of large forms of relief on the location and configuration of the zones.  相似文献   
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