Assessment of the geomorphic impacts of forestry in British Columbia

Timber harvesting in British Columbia influences (a) forest hydrology; (b) fluvial geomorphology; (c) terrain stability; and (d) integrated watershed behavior. Impacts on forest hydrology are well understood and include incre ased average runoff, total water yield, increased storm runoff and advances in timing of floods. Stream channels and valley floors are impacted differ ently by fine sediment, coarse sediment and large woody debris transport. T errain stability is influenced through gully and mass movement processes th at are accelerated by timber harvesting. Impacts on integrated watershed be havior are assessed through disturbed sediment budgets and lake sediments. The Forest Practices Code (1995) is a significant step towards sustainable management of the land in so far as it attempts to minimize these geomorphi c impacts of forest in B. C.