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Study locations
Vancouver Island study location:
- Near Nitinat Lake, southwest Vancouver Island
- Winter floods from rainstorms
- Mostly rocky terrain, coarse grained soils
- Study referred to as “Nitinat”
Boston Bar study location:
- All streams located within Anderson River basin, east of Boston Bar
- Almost Interior conditions
- Snowmelt dominated floods
- Deep, fine-grained till soils
- Study referred to as “Anderson”
Slash in streams studies
Study methods used in the two locations:
- Select streams that were logged 5 to 15 years ago, with the slash left in the stream
- Inventory amount and types of disturbance
- Collect data on width, depth, gradient, and other variables that may be used to predict disturbance
- Streams are less than 5 m wide
Disturbance includes:
- Large sizes of woody debris are transported
- Large amounts of woody debris are transported
- Frequent and large woody debris jams
- Channel and bank erosion
Severe disturbance
![Image of a severe disturbance. Click image to enlarge. Image of a severe disturbance. Click image to enlarge.](https://www2.gov.bc.ca/assets/gov/environment/air-land-water/land/soils-research/gullies-and-streams/severe_slash_movement1_sm.jpg)
Click image to enlarge.
Variables assessed to predict channel disturbance:
- Channel width and depth
- Gradient
- Channel location
- Channel and bank types
- Size of sediment moving
Study results