Scale-specific effects of disturbance and environment on vegetation patterns of a boreal landscape

摘要

An array of ecological factors like available resources, disturbance regimes at varying spatio-temporal scales and environmental conditions, influence forest succession and alter the resulting landscape patterns. Disturbance regimes create spatio-temporal patterns of tree mortality and thus a mosaic of forest ages. Environmental factors such as elevation, slope, aspect, soils, and vegetation edges may increase spatial variability in disturbance regimes, which may then translate into spatial patterns of forest vegetation. Insights into such ecological processes and their interactions are vital in setting conservation targets, assessing current managed systems, or in making ecologically informed management decisions. Thus the main objectives of our study are (i) to investigate the relationships between vegetation patterns of a boreal landscape and its disturbance history, and (ii) to test whether these relationships contrast with environmental heterogeneity. We also would like to examine whether the vegetation responses to the interplay of disturbances and environment vary as a function of the spatial scale of observation. We used recent lidar and imagery of parts of North American mixedwood boreal forest to develop accurate generalisations across multiple scales across the landscape, spatial patterns of disturbances, environmental heterogeneity, structure and composition of vegetation. The forest responses at multiple resolutions were investigated using wavelet analysis.