Wetlands

Wetland

• Transitional area between upland and aquatic ecosystems

  • sometimes wet and sometimes dry

• defined by hydrology, soils, vegetation

Looking at Wetlands Hydrology

• intermittently to permanently flooded

• Presence or evidence of water

Wetland Soils( Hydric soils)

• Saturated long enough to develop anaerobic conditions

• When soils are exposed to anaerobic conditions

Hydric Soils are indicated by 

•Gley (have iron but has been reduced)near surface

•Muck: the settled organic matter and sediment

•Histic epipedon

•Hydrogen sulfide( rotten egg), complete decomposition

Wetland Vegetation

hydophytic(a plant that grows in water or very wet soil)

vegetation and land as you go upland

larger veg and drier land

watertable

• dividing line in subsurface between the unsaturated zone and the saturated zone

watertable in wetlands

fluctuates

Wetland Formation

we have a seasonal abundance of water

the water could be from

• surface water from overflow/flooding

• Groundwater

• or it could be a combination

where does runoff accumulate

in low line areas; floodplains; bottoms of slopes

geology impact on wetlands

influence the topography

the soil properties

rocks( imp/permeabler)

cedar Bog, OH

• wetland that formed in wet developed soils/galcial outwash(sand and gravel)

• why there: bedrock( water cant penetrate)

Coastal wetlands

• Marine

• Estuarine(river to ocean)

Terrestrial wetland

(lake wetlands)

Riverine

•Lacustrine

•Palustrine

•Palustrine

• Any other non-tidal system(any wetland in terrestrial)

• Most upland wetlands

  • Bog

  • Fen

  • Swamp

  • Marsh

Bog

• is fed from surface water runoff

• leaves: infiltration into ground

• acidic

Fen

• fed by GW

  • it can have streams

• less acidic

  • more neutralize

swamp

• Stable, perennial vegetation dominated by trees

• Usually inundated(flooded/overwhelmed) with water

Marshes

• Short-lived or seasonal vegetation

  • Dominated by grasses

• Seasonal wetlands, moisture often from groundwater

• Can be coastal

  • Salt marshes

Wetland Function

• Groundwater recharge

• Flood reduction

• Surface water storage

• Water quality improvement

• Biodiversity

• stream energy gets disapated

• filtering affect

Primary processes of wetland

• Uptake and transformation of nutrients by plants and microorganisms

• Breakdown and transformation of pollutants by plants and microorganisms

• Filtration and chemical precipitation through contact with substrate

• Settling of suspended particulate matter

• Chemical transformation of pollutants (i.e. ammonification of nitrogen)

• Absorption and ion exchange on the surfaces of plants, sediment, and litter

• Predation and natural die-off of pathogens

Wetland issues

• Destruction

• Unattractive

• Unusable land

• Dangerous

• Swamp Wetlands Act (1850s)

  • Targeted draining and filling wetlands

  • By 1980, over half of pre-European wetlands gone

Ohio Wetlands

•90%+ of Ohio’s wetlands destroyed

•Over 4.5 million acres

Ohio Wetlands lost due

•Dredging to become ponds

•Channelization for waterways

•Filled for urban development

•Drained for agriculture

Drainage Goal

to increase air in soils (reduce water)

• Drainage pipes and ditches to remove water from pores in root zone

• Wetland soils are nutrient-rich

  • Remove water makes these nutrients available for agriculture

pipes

lower water table

allows for faster warming in spring

faster drying in spring

crops can be planted sooner

capture of drained water

benefits of capturing drained water

• water source

concerns with capturing wetland water

dirty water-has fert., nutrients. pesticides

why we drain wetlands

• increase O2 and lower the watertable