Rehabilitation of Boreal Streams Channelized for Log Transport

摘要: Circumpolar boreal forests are an important source of timber products, as well a significant global biome in the Northern Hemisphere. Historically, structure and functioning stream ecosystems this forest region have been impacted by practice floating logs downstream means transport. Rapids were destroyed when boulders large woody debris removed from channel placed riparian zone. Also, shallow riffle areas dredged to produce debris-free uniform depth. The resulting lack habitat heterogeneity produced faster velocities impacting decline species diversity population sizes compared natural streams (Tikkanen et al. 1994; Kelso & Cullis 1996; Huusko Yrjana 1998; Haapala Muotka Laasonen 1998). Since early 1980s method transport has abandoned Europe Canada now that it is less expensive truck directly mills. Presently, there trend both rehabilitate resemble their original ecological (Kelso Cowx Welcomme Tikkanen Scruton purpose paper describe: 1) criteria for determining target be rehabilitated; 2) physical biological impacts streams; 3) methods used rehabilitation projects.