10,000 Years Institute - scientific research for natural resource management from Seattle, WA to Lake Baikal, Russia.
10,000 Years Institute - scientific research for natural resource management from Seattle, WA to Lake Baikal, Russia.
Headwater Streams

Functional, complete riparian forests provide critical ecological services throughout the stream network. Even in steep headwaters, a mature riparian forest provides shade, stream bed and bank stability, cover, and energy sources for aquatic food webs. Ineam wood derived from riparian forests reduces local stream gradients, provides ineam cover and habitat structure, and functions to retain coarse sediment crucial for fish habitat (Figure 1). Destabilization of steep stream beds can result from intensive land use such as logging in headwater riparian forests. Destabilization results in massive sediment movement over a short period of time, destroying complex habitats in steep areas and downstream (Figure 2).

10,000 Years Institute is studying the link between riparian forest structure and the stability of ineam wood and sediments. This research will provide a basis for understanding whether current forest practice rules are sufficient and appropriate to protect the integrity of headwater streams and the river network to which they are connected. Data collection, analysis and reporting are in progress; see our 2003 Poster Presentation (pdf format - 5.2MB may load slowly please be patient) for a summary of results to date.

Snider Creek, tributary to the Hoh River, Olympic National Park, WA Virginia Falls, Hoh River Basin, Olympic National Park
Figure 1. (click photo to enlarge) A natural distribution of wood and sediment in Snider Creek, tributary to the Hoh River, Olympic National Park, WA. Wood has several important ecological functions in the stream, including provision of a source of organic material for food, shelter for fish and aquatic macroinvertebrates, sediment retention, and increasing habitat heterogeneity. Figure 2. (click photo to enlarge) Site of a recent debris flow on Virginia Falls in the Hoh River Basin on the Olympic peninsula, WA. The bare creek bed shows how the debris flow eliminated vegetation and stream substrate.