1. Biology 20

2. Terrestrial Ecosystem Ecosystems found anywhere on earth that is not covered by water. Alberta’s terrestrial ecosystems are found within two major biomes: (A) Taiga (B) Grassland Within these biomes, you may find the following ecosystems: Taiga Ecosystem / Muskeg Ecosystem / Grassland Ecosystem / Deciduous Forest Ecosystem

3. AQUATIC ECOSYSTEMS Two types of aquatic communities: Marine  abundance of salt Freshwater  lack salt Estuary – where a river flows into the ocean, allowing the two communities to meet. Contains “Brackish” water, mixture of fresh and salt.

4. LAKE ZONES LITTORAL ZONE Most productive area, greatest amount of photosynthesis. Shallow enough for rooted aquatic plants Access to sufficient sunlight penetration

5. LAKE ZONES LIMNETIC ZONE Open area of the lake that extends to the depth where sunlight penetration is not adequate. No photosynthesis Home for most animal life and free floating plants PROFUNDAL ZONE Sunlight cannot penetrate AKA the “Benthic Zone” Home for bottom feeders that feed on decaying matter.

6. LAKE ZONES Draw Diagram on Page 99 On diagram, indicate... 1. area of most photosynthesis 2. area of most animal life 3. area of bottom feeders 4. benthic zone

7. ABIOTIC FACTORS AFFECTING AQUATIC ECOSYSTEMS FACTOR #1  Chemical Environment 3 considerations to describe chemical environment: A. Is the water fresh-water or salt-water? B. How much O 2 is dissolved in the water? C. What amount of other substances is present in the water? (nitrogen, phosphorus, etc)

8. FACTOR #2  Temperature Increasing Depth = Decreasing Temperature FACTOR #3  Sunlight Exposure to sunlight decreases with increasing depth from the surface. What type of organisms live in conditions with no sunlight?

9. FACTOR #4  Water Pressure Pressure increases with an increase in depth Organisms can move freely through the ocean, but are limited by how much they can move up and down due to large changes in pressure. At a depth of 10m, the pressure is double what it is at the surface, and increases by 100 kPa for every 10 m of depth. (average ocean depth = 4000 m)

10. Questions! Page 100 1 – 7