Relationships between canopy transmittance and stand parameters in Sitka spruce and Scots pine stands in Britain
Authors: Hale, Sophie E.; Edwards, Colin; Mason, W. L.; Price, Martin; Peace, Andrew
Source: Forestry, Volume 82, Number 5, 7 December 2009 , pp. 503-513(11)
Publisher: Oxford University Press
Abstract:The changing emphasis within British forestry from a clearfell/replant system focussed on timber production, to multipurpose forestry encompassing biodiversity and recreation, has resulted in a need for changes to forest management. Manipulation of the forest canopy through thinnings is a powerful tool for forest managers to modify the canopy transmittance, and therefore the below-canopy light levels. This helps to achieve specific objectives such as habitat management or seedling growth as part of transformation of an even-aged stand to a continuous cover forestry regime. In this study, hemispherical photography was used to assess canopy transmittance in a range of Sitka spruce (Picea sitchensis (Bong.) Carr) and Scots pine (Pinus sylvestris L.) stands in Britain. Species-specific relationships were developed between canopy transmittance and easily-measured stand parameters. The models that provided the best fit to the data were based on basal area and stocking for Sitka spruce and basal area alone for Scots pine. The models indicate that a Sitka spruce stand with a basal area of 30 m2 ha1 should have a stocking density <450 stems ha1 to favour growth of Sitka spruce seedlings. Similarly, a Scots pine stand should have a basal area <27 m2 ha1 to achieve transmittance suitable for growth of Scots pine seedlings. In conjunction with a knowledge of the light requirements of different vegetation types, these models can provide a valuable contribution to guidance on current and changing forest management practice.
Document Type: Research Article
Publication date: 7 December 2009
- Forestry publishes refereed papers on all aspects of research, practice and policy that promote the sustainable development of forests, woodlands and trees. In considering suitability for publication attention is given to both the originality of contributions and their practical application. Preference is usually given to work undertaken in the temperate and/or boreal zones; only articles of exceptional merit from tropical zones will also be considered.