Simulating the impact of landscape-level biodiversity guidelines: A case study

Abstract

British Columbia, along with most of the rest of North America, is becoming preoccupied with emulating natural landscape patterns under the auspices of ecosystem management. With their Biodiversity Guidebook, BC developed one of the first collections of rules for landscape management purposes. The landscape-level rules developed therein are representative of those being developed in other areas of North America. This research compared, in simulation, a range of patterns created by these guidelines for a landscape in central BC, against those created from the historical 60 hectare two-pass system, and a "natural" disturbance regime. Results indicate that the biodiversity guidelines created more natural levels of patch sizes, interior forest area, and seral stage percentages compared to the two-pass system. However, the guidelines failed to create more natural rates of disturbance, or ranges of patch sizes and interior areas in old and mature forest. Furthermore, the implied degree of naturalness of the low, medium, and high biodiversity options did not necessarily hold true. The simulation results presented in this paper show that the concept of mimicry involves much more than originally had been supposed, and that there are limits to the degree to which mimicry can be used as a landscape management paradigm with our current knowledge and ability. A strategy for working towards a natural landscape pattern program for forest management is discussed. Key words: landscape level, biodiversity, simulation, disturbance