WETLAND HYDROLOGY:

BIOLOGICAL EFFECTS OF HYDROLOGY ON WETLANDS

VEGETATION COMPOSITION

A. Decreased diversity

Causes

Riparian forest example

B. Increased diversity

Causes

Peatland example

C. Disturbance niches

PRIMARY PRODUCTIVITY

A. Pulse enhancement

B. Swamp forest example

C. Riparian wetland example

D. Tidal systems

ORGANIC ACCUMULATION

A. Decomposition

Alternating wet/dry environments

Continually waterlogged environments

Well-aerated flow environments

B. Export

NUTRIENT CYCLING

A. If productivity and decomposition are high, cycling will be high

B. Nutrient sources: precipitation, river flooding, tides, surface and groundwater

C. Nutrient availabilities which are tied to anaerobic conditions

N - denitrification

P - soluble in anoxic sediments and water columns

BIOTIC CONTROL OF WETLAND HYDROLOGY

A. Peat

B. Sediment trapping

C. Nutrient retention

D. Atmosperic losses

Water shading

Transpiration

E. Biotic controls by animals