1. Biology of Seaweeds – Kelp Beds and Forests

2. Biology of Seaweeds – Kelp Beds and Forests
Kelp is the collective term referring to very large brown algae dominating
cold water regions of the earth.

3. Biology of Seaweeds – Kelp Beds and Forests
If the algae do not form a
surface canopy, the algal
communities are referred to
as kelp beds.
If the algae do form a
surface canopy, the algal
communities are referred to
as kelp forests.

4. Biology of Seaweeds – Kelp Beds and Forests
Kelp beds are dominated by the genera Laminaria, Pterygophora, and Ecklonia.
Kelp forests are dominated by the genera Macrocystis and Nereocystis.
In contrast to most algae, the kelp forest algae grow to 30 meters or more.
These algae actually block most of the sunlight, resulting communities of
“understory” algae forming layers bellow them…
Kelp forest communities are also highly productive areas;
e.g. Nereocystis luetkeana has been recorded with growth rates of 6 cm/day
and Macrocystis pyrifera commonly grows 50 cm/day or more…

5. Biology of Seaweeds – Kelp Forests and their “Understory” Communities
1. Small filamenous
species.
2. Bottom-canopy
plants.
3. Understory-canopy
4. Midwater and
surface-canopy

6. Biology of Seaweeds – Life cycle of typical kelp
In case of Macrocystis, the typical large plant seen is actually the asexual sporophyte
generation… (note that this is not the case for all algae…)
Typical alternation of generations…

7. Biology of Seaweeds – Kelp Forests Ecosystems

8. Typical zonation and distribution
of organisms in various California
kelp forests…