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Trend Detection for Stream Physical Habitat Elements: Washington/Oregon
Linear Trend Detection
- Hypothesis test: Slope = 0
- Power: If a trend is present, what is the likelihood of detecting it?
Sources of Data for Washington/Oregon Example
Studies & Sample Sites
- Essential Stream Physical Habitat Elements (Identified by Expert Panel)
- Channel Dimensions
- Gradient
- Substrate Size & Type
- Hab. Complexity & Cover
- Riparian Vegetation Cover & Structure
- Channel-Riparian Interaction
- Anthropogenic Alterations
Power to Detect 2%/Year Trend with power = 0.8
Time to Detect a 2%/Year Trend for several Habitat Indicators & Influence of Variance Components