Freshwater Biomes - Key Points from Khan Academy Article

What is a Biome?

A biome is a community of plants and animals adapted to a specific climate.
Aquatic biomes are water-based and include both freshwater and marine environments.
The characteristics of aquatic biomes are heavily influenced by dissolved oxygen and nutrient concentrations.

Freshwater biomes contain water with little or no salt and include ponds, lakes, streams, and rivers.
They are a crucial source of drinking water.

Ponds: Smaller, possibly seasonal water bodies.
Lakes: Larger, more permanent, and consist of four main zones:
- Littoral Zone: Near-shore, shallow, with abundant sunlight and nutrients supporting diverse life.
- Limnetic Zone: Open-water zone, sunlit, where most photosynthesis occurs, supporting phytoplankton and zooplankton.
- Profundal Zone: Deep-water, too dark for photosynthesis, supports fish adapted to cooler, low-oxygen water.
- Benthic Zone: Lake bottom, rich in decomposers and organisms feeding on decaying matter.

Flowing bodies of water, crucial for landscape drainage and erosion.
Characterized by three zones:
- Source Zone: High elevation, fast-moving, oxygen-rich, nutrient-poor waters with few plant species.
- Transition Zone: Wider, slower-moving waters, less oxygen, more nutrients, supporting diverse life.
- Floodplain Zone: Flat, wide, warm, nutrient-rich waters supporting abundant plant and animal life.