1. Landscape Disturbance
Disturbance defined as:
Relatively discrete event in time
Disrupts possible multiple hierarchal levels
White and Pickett 1985

2. Landscape Disturbance
Disturbance defined as:
Changes resources, substrate, or physical environment
White and Pickett 1985

3. Landscape Disturbance
Disturbance defined as:
Catastrophes to more subtle fluctuations
Ultimately causes “significant change in system”
White and Pickett 1985

4. Landscape Disturbance
Perturbation – change in parameter (state variable); departing from normality

5. Landscape Disturbance
Characteristics of Regime:
Area/size
Spatial dist’n
Frequency
Recurrence interval
Predictability
Intensity/severity
Synergisms
Feedbacks

6. Landscape Disturbance
Type Agent
Physical
Biological
Interaction
Origin of Agent
Endogenous
Exogenous

7. Disturbance Types

8. Landscape Disturbance
Disturbance history
Time scale
Context

13. Landscape Disturbance
Complexity of interactions
Macroclimatic patterns
Landscape position
Vegetation
Boose et al. 1994

14. Landscape Pattern & Spread of Disturbance
Generalities possible?
If disturbance spreads within same cover type, then greater heterogeneity should retard spread (e.g., spruce budworm, lower intensity fires)

15. Landscape Pattern & Spread of Disturbance
Generalities possible?
If disturbance spreads between cover types or is edge-enhanced, then increased heterogeneity should enhance spread (e.g., windthrow, tent caterpillar)

16. Landscape Pattern & Spread of Disturbance
Generalities possible?
If disturbance is severe enough or of large enough extent, then may function independent of landscape pattern