<p>Almost one-third of Earth’s forest area occurs in boreal regions, with vast expanses dominated by conifers and sometimes with major components of deciduous tree species. Chronic processes happen all the time, including competition between trees and with understory vegetation, and between animals and plants, shaping the development of boreal forests across years and decades. Major events (such as fires, insect outbreaks, and storms) create patches with legacies that last decades to centuries. By number, almost all events in boreal forests occur in small patches (< 1–10 ha), but a small number of very large events (> 1000 ha, sometimes > 100,000 ha) shape the majority of boreal landscapes. Forest structure and function are not uniform within patches, so spatial variation at scales far smaller than average patch sizes are important for most species of trees, other plants, fungi, and animals. The sizes of forest events across most boreal landscapes remains very large across most of the hemisphere, but some areas (particularly Fennoscandia) have reduced the frequency and sizes of fires though intensive land use. The strongest spatial interactions in forests occur at scales of less than tens of meters, such as neighborhoods of trees dominated by the largest trees. Some aspects, such as habitat suitability for some mammals and birds, may depend on larger patch sizes with limited influence of edges and large areas of interior-forest conditions. Management with very small patch sizes may limit development of open areas and large areas with interior-forest conditions. Aspects of spatial scale distinguish rotational forestry from continuous cover forestry; current scales of harvesting operations for both systems are far smaller than patches created historically by fires (but in some cases similar to insect outbreaks and storms). Forests are not fragile, and they do not have strict limits on possible composition or structure. A range of “distant from nature” systems would be viable across boreal landscapes, including continuous cover forestry that creates small patches with frequent removal of small numbers of trees. Species that thrive at edges between small patches would be favored in continuous cover landscapes, with less suitability for species that do well in large areas of open/young forests, or large interior areas of older forests. Forest policies and management approaches may be unlikely to aim at matching historical scales of ecology at landscape scales. Undesirable outcomes of distant from nature forestry might be reduced with better appreciation of the spatial ecology of boreal forests across years and centuries.</p>

Assmann review: spatial ecology of rotational and continuous cover forestry in boreal landscapes

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发表日期：

2025年1月6日

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Dan Binkley

摘要

Almost one-third of Earth’s forest area occurs in boreal regions, with vast expanses dominated by conifers and sometimes with major components of deciduous tree species. Chronic processes happen all the time, including competition between trees and with understory vegetation, and between animals and plants, shaping the development of boreal forests across years and decades. Major events (such as fires, insect outbreaks, and storms) create patches with legacies that last decades to centuries. By number, almost all events in boreal forests occur in small patches (< 1–10 ha), but a small number of very large events (> 1000 ha, sometimes > 100,000 ha) shape the majority of boreal landscapes. Forest structure and function are not uniform within patches, so spatial variation at scales far smaller than average patch sizes are important for most species of trees, other plants, fungi, and animals. The sizes of forest events across most boreal landscapes remains very large across most of the hemisphere, but some areas (particularly Fennoscandia) have reduced the frequency and sizes of fires though intensive land use. The strongest spatial interactions in forests occur at scales of less than tens of meters, such as neighborhoods of trees dominated by the largest trees. Some aspects, such as habitat suitability for some mammals and birds, may depend on larger patch sizes with limited influence of edges and large areas of interior-forest conditions. Management with very small patch sizes may limit development of open areas and large areas with interior-forest conditions. Aspects of spatial scale distinguish rotational forestry from continuous cover forestry; current scales of harvesting operations for both systems are far smaller than patches created historically by fires (but in some cases similar to insect outbreaks and storms). Forests are not fragile, and they do not have strict limits on possible composition or structure. A range of “distant from nature” systems would be viable across boreal landscapes, including continuous cover forestry that creates small patches with frequent removal of small numbers of trees. Species that thrive at edges between small patches would be favored in continuous cover landscapes, with less suitability for species that do well in large areas of open/young forests, or large interior areas of older forests. Forest policies and management approaches may be unlikely to aim at matching historical scales of ecology at landscape scales. Undesirable outcomes of distant from nature forestry might be reduced with better appreciation of the spatial ecology of boreal forests across years and centuries.