National Forest Inventory by Aggregation of Existing Inventories : National Forest Inventories

1993

S. 25-31

4 Lit. Ang.

Unselbständiges Werk

200103934

Canada's Forest Inventory is aggregated from various sources. Most of these sources are provincial management inventories based on forest type maps made from air photos. The national inventory takes advantage of an infrastructure of source inventories that are basically similar. Procedures have been developed to combine inventories with different specifications, and to overcome gaps in the data. The inventory in this form is now entering its third five-year cycle and uses modern computer technology to handle georeferenced data. The Canadian approach is similar to that of the Global Forest Assessment of FAO/ECE, but differs from most of the older national forest inventories based on sample plots. The Canadian practice has several advantages such as cost relative to benefit, agreement between agencies, and opportunities to combine the inventory with other categories of spatially referenced information. There are disadvantages, too, especially the slow response to certain new information needs and some problems created by the different dates and specifications of the source inventories. The inventory cannot monitor change reliably. It is felt that the addition of a low intensity multi-level sampling scheme to monitor overall change would improve the design.