Biomes II

Students have been learning all the different biomes that exist in the oceans. Most people have heard of coral reefs and think about the beach, but there are actually many different biomes in the ocean. Not all biomes are found at the bottom of the sea. Along coasts you can find rocky coasts, sandy beaches, salt marshes, mangroves, sea grass beds, kelp forests, and fouling communities.

Kelp forests are dominated by kelp that can grow to 300 feet tall. The kelp is held near the surface by lots of air bladders. Kelp forests are important because they provide a lot of substrate and habitat for organisms to live, hide and eat.

We also discussed sea grass beds. Sea grass is super-important for stabilizing the substrate and holding the sand down. This promotes water clarity and decreases turbidity. Nothing eats sea grass when it is alive except for manatees. Everything else eats it after the bacteria have decomposed it a bit.

Salt Marshes are one of the most productive ecosystems, but nothing eats the salt marsh grass when its alive... once the anaerobic bacteria break it down into black mush, then other organisms eat it.

Mangroves are trees that can grow in salt water. They have crazy prop roots or finger like roots called pneu- mato- phores that stick up out of the water so the tree can get oxygen during high tide. The roots provide a lot of substrate that a lot of fouling organisms will colonize and use as habitat. 

Photic vs Aphotic is an odd one involving the light and dark zones of the ocean. Some organisms hide in teh dark aphotic zone during the day and migrate up to the surface (the photic zone) at night to eat the phytoplankton. Predators also migrate to eat the things that are eating the phytoplankton. 

There is a lot of information to learn this unit. The Unit 3 Test is one of the hardest of the year.