Like most guidelines used in natural resource management, these have been developed from a combination of scientific evidence and informed professional judgment. They represent an attempt to integrate society’s desire both to generate commercial forest products and to ensure the conservation of biological diversity in managed forests. A companion document, summarizing the scientific literature that supports the ecological concepts in this guidebook, is currently in preparation.
We recognize that this guide has its limitations, but nevertheless believe it marks a significant step towards responsible stewardship of all the resources in the forest. As scientific understanding and social values change over time, so the scientific and value-based choices presented here will be revisited.
In summary, the guidebook provides direction on:
This guidebook is based on, and replaces, the following joint publications of the B.C. Ministry of Forests and the Ministry of Environment, Lands and Parks:
Developing a biodiversity conservation strategy that is based on a variety of management strategies for individual species is neither feasible nor effective. The impact of forest management practices on many species is unknown and certain practices that benefit some species are often detrimental to others. Recommended instead is the development of an ecosystem management approach that provides suitable habitat conditions for all native species. In this way, habitat diversity is used as a surrogate to maintain biodiversity. Key biodiversity concepts are described in Appendix 1.
At the same time, however, special efforts may be needed to protect the habitat of species known to be at risk, such as threatened, endangered, or regionally important species. Specific strategies for addressing these species are outlined in the Managing Identified Wildlife Guidebook.
Planning to maintain biodiversity should occur at a variety of levels all of which are linked hierarchically (Figure 1): provincial (such as the provincial biodiversity strategy), regional (such as the planning being carried out by the Commission on Resources and the Environment), subregional (such as the planning being carried out through Land and Resource Management Planning), landscape, and stand. This guidebook applies to two of those levels: landscape and stand.
The biodiversity management approach described here is based on ecological principles and will be refined over time as new knowledge is obtained and management practices evolve. The underlying assumption of this approach is that all native species and ecological processes are more likely to be maintained if managed forests are made to resemble those forests created by the activities of natural disturbance agents such as fire, wind, insects, and disease. It has been these natural ecological processes, along with burning by aboriginal peoples, that have determined the composition, size, age, and distribution of forest types on the landscape, as well as the structural characteristics of forest stands.
Figure 1. Levels at which the maintenance of biodiversity can be considered (provincial level not shown).
Principles and assumptions on which this guidebook is based:
– maintaining a variety of patch sizes, seral stages, and forest stand attributes and structures across a variety of ecosystems and landscapes
– maintaining connectivity of ecosystems in such a manner as to ensure the continued dispersal and movement of forest- and range-dwelling organisms across the landscape
– providing forested areas of sufficient size to maintain forest interior habitat conditions and to prevent the formation of excessive edge habitat.
– a system of protected areas at the regional scale
– provision for a variety of habitats at the landscape scale
– management practices that provide important ecosystem attributes at the stand scale.
As well as these, several other guidebooks—notably those that address terrain stability, watershed assessment procedures, community watershed management, and visual landscape management—involve land zoning and recommend certain constraints to harvesting and grazing activities. Collectively these guidebooks provide planners with further direction on how land might be zoned into the long-term leave areas needed to minimize the effects on biodiversity of habitat fragmentation and old-growth conversion.
The administrative process for establishing, varying or canceling landscape units and landscape unit objectives is described in the Higher Level Plans Guidebook.
Figure 2. The relationship between the Biodiversity Guidebook and the Riparian Management Area and Managing Identified Wildlife guidebooks. This conceptual diagram illustrates how the recommended practices in the different guidebooks are designed to ensure that the critical requirements of all species are protected. The practices in the Biodiversity and Riparian Management Area guidebooks act as the coarse filter, protecting most species; the practices in the Managing Identified Wildlife Guidebook act as the fine filter, protecting those species whose habitat requirements are not adequately covered by the coarse filter guidelines.