Effects of Contemporary Forest Management Practices on the Physical, Chemical, and Biological Characteristics of Headwater Streams

Commercial forestry is a dominant economic activity in the Pacific Northwest and the region has a long history of timber harvest. Balancing this economic engine with ecosystem services provided by headwater streams, including high-quality water supply, fish production, biological diversity, and recreational opportunities requires careful management of riparian and upland forests. Pioneering studies within the region, at Carnation Creek and the Alsea Watershed Study, documented the hydrological and biological responses of streams to timber harvest practices of the mid-20^th century. In so doing, these studies played an important role in the development of forest management regulations that were intended to safeguard aquatic resources while allowing timber harvest. However, results from this early research do not necessarily reflect the effects of contemporary forest practices, which have advanced considerably in the decades since those studies were initiated. Contemporary timber harvest occurs primarily on private industrial timber lands and has shifted from harvesting old growth or naturally-regenerated mature timber, to logging planted stands at relatively short stand rotation intervals, using pre-existing road networks, all forest practice regulations that have become progressively more stringent since the 1970s. The effect of these changes in forest practices on aquatic ecosystems has not been fully evaluated.