aquatic biomes

Marine Biome

Includes oceans, coral reefs, estuaries; covers about 70% of Earth's surface

Freshwater Biome

Includes lakes, rivers, streams, and wetlands; low salinity

Photic Zone

Upper layer of water in the ocean that receives enough sunlight for photosynthesis

Aphotic Zone

Deeper layer of ocean water that lacks sufficient sunlight for photosynthesis

Benthic Zone

Bottom of a body of water; consists of sand and sediment

Pelagic Zone

Open ocean area not close to the bottom or near the shore

Intertidal Zone

Area between high and low tide; organisms adapt to changing conditions

Estuary

Area where freshwater from rivers meets saltwater from the ocean; high productivity

Wetland

Area saturated with water, such as swamps and marshes; supports diverse plant and animal life

Coral Reef

Marine ecosystem characterized by reef-building corals; high biodiversity

Upwelling

Process where deep, cold, nutrient-rich water rises to the surface

Thermocline

Layer in a body of water where temperature changes rapidly with depth

Oligotrophic Lake

Deep, clear lake with low nutrient levels and low productivity

Eutrophic Lake

Shallow lake with high nutrient levels and high productivity

Hypoxic

Low oxygen conditions, often due to excessive nutrient pollution