Monitoring landscape change in multi-use west-central Alberta, Canada using the disturbance-inventory framework

Abstract

Human disturbances are a major driver of biodiversity declines world-wide, and the intensely used Alberta forest landscape is no exception to this trend. Monitoring of such large areas is typically conducted via multi-temporal land-cover maps from remote sensing, but automated and efficient procedures for reliable, operational applications have yet to be fully developed. In an effort to contribute to this need, we developed an innovative approach to landscape monitoring: the disturbance-inventory framework, which is applied for the first time as described here to monitor annual changes in an 8800-km2 multi-use landscape in west-central Alberta, Canada. Using this framework, we (1) report on the spatio-temporal distribution of industrial disturbances such as harvesting cutblocks, oil and gas wells, coal mines, and road/pipelines; and (2) track the associated annual changes in land-cover composition and configuration between 1998 and 2005. To enable spatially explicit analyses within the study area, we divided it into 178, 49km2-square landscape cells. The overall area-based annual rate of change of 0.62% for this multi-use may be considered moderate compared to other regions, where change was mainly shaped by a single use, i.e., forestry. However, the spatially explicit nature of our analysis revealed that the eastern half of the study area is subject to considerably higher rates of change, mainly due to the concurrent appearance of disturbances from forestry and the oil and gas industry. The western half, by contrast, is more restricted by rugged terrain and fewer roads. The average distance to disturbance features across the entire study area decreased from 1500m to 1200m over the seven years. Total forest area, mean and largest patch size, and mean shape index all decreased consistently over the same period. The detected rapid change and associated fragmentation call for ongoing monitoring of this and other multi-use landscapes, which could be undertaken using this framework.