Design of an environmental monitoring program using NDVI and cumulative effects assessment

This paper presents a sampling design for monitoring spatial and temporal changes in forest health in the Upper Elbow River Basin, in Alberta, Canada. The procedure involved a combination of cumulative effects assessment and remote sensing techniques for selecting sampling sites based on physical and anthropogenic features. Normalized difference vegetation index (NDVI) was the indicator of forest health. Unique combinations of slope, aspect, soil moisture, NDVI, vegetation type, and the zone of influence of human activities were used to select pairs of sampling sites. Each pair consisted of a site within the zone of influence and one outside the zone. Spatial discrimination analysis was the method used for reclassification. The analysis suggested that 58 pairs would be appropriate for monitoring. NDVI was negatively correlated with dry soils and increased with the slope. To various extents, most of the species displayed NDVI values between 0.20 and 0.59. The density of linear disturbances (km/km(2)) was estimated and it showed that one of the three sub-catchments, the Bragg Creek, has levels of human disturbance above the value considered optimal for wildlife habitat suitability.