Wetlands and Aquatic Ecosystems Notes

Wetlands are transitional areas between uplands and open water, crucial for biodiversity and ecosystem services.

Classification:

  • Ecological System: Marine, Estuarine, Palustrine, Riverine, Lacustrine.

  • Vegetation: Submerged bed, emergent marsh, swamp, scrub-shrub.

  • Other: Landscape position, water chemistry.

Key Functions:

  • Flood storage and desynchronization.

  • Water purification: Sediment and nutrient (Nitrogen, Phosphorous, Sulfur) removal/cycling.

  • Biomass production.

Lakes:

  • Zones: Littoral, limnetic, profundal with unique biota.

  • Turnover: Affects oxygen and nutrient distribution; stratification.

Rivers (River Continuum Concept):

  • Gradient, energy, nutrients, and species change from headwaters to downstream.

Water Chemistry:

  • pH, dissolved oxygen, sediment levels are critical for aquatic life; Eutrophication impacts water quality.

Stream Health:

  • Macroinvertebrates indicate water quality (pollution sensitivity, functional roles - shredders, collectors, scrapers, predators).

Values:

  • Habitat, flood protection, educational/recreational value.

  • Lakes have distinct zones (littoral, limnetic, profundal) with unique biota and undergo turnover, affecting oxygen and nutrient distribution.

  • Rivers are viewed along their entire length in the River Continuum Concept, with changes in gradient, energy, nutrients, and species from headwaters to downstream.

  • Water chemistry aspects like pH, dissolved oxygen, and sediment levels are critical for aquatic life.

  • Eutrophication, both natural and human-caused, impacts water quality.

  • Stream health is assessed via macroinvertebrates, which indicate water quality based on their pollution sensitivity and functional roles (shredders, collectors, scrapers, predators).

  • Wetlands provide habitat, protect against floods, and offer educational and recreational value.