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Coastal dunes are susceptible to human disturbance from activities
which change dune soils, microclimate and vegetation.
Dune soils/sand
| Changes |
Effects |
| Movement of surface
material |
Changes dune topography |
| Compaction |
Makes soil less
hospitable to plant germination and plants taking root |
Microclimate
| Changes |
Effects |
| Greater fluctuations
in soil and air temperatures |
Produces a harsher
environment for vegetation
|
| Higher moisture
contents |
Aids plant survival |
Vegetation
| Changes |
Effects |
| Decreased plant
height |
Increases vulnerability
to wind erosion |
| Decreased species
richness |
Lowers ecological
health of area and increases vulnerability to erosion |
| Decreased percent
cover |
Increases bare ground
and vulnerability to erosion |
| Decreased plant
density |
Increases bare ground
and vulnerability to erosion |
|
Topography changes when steps push sand downslope
(to the left in photo)
(Hoffmaster State Park in Nov 2005.)
Dune trail is bare of vegetation and exposed to temperature extremes
and wind. (Hoffmaster State Park in June 2002.)
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