ERTH 2403 Lecture 9: Chapter 14

• School: Carleton University
• Department: Earth Sciences
• Course: ERTH 2403
• Professor: Hafida El Bilali

Document Summary

Types of photosynthetic marine organisms: mictroscopic algae phytoplankton, macroscopic algea seaweed, photosynthetic bacteria. Golden algae: diatoms: siliceous tests, coccolithophores: calcareous (calcium carbonate) plates. Dinoflagellates: red tide (harmful algal bloom, toxins, human illness. Some from a neurotoxin in mussels and clams. Red tides (seasonal bloom: usually toxic, some are bioluminescent. The combination of these two is what causes the production of light. Absorb dim blue light in euphotic zone. Possibly great photosynthetic contributors where the other phytoplankton cannot function. Seaweeds: 7000 specieves are multicellular algae, varity of sizes and shapes, flexible and strong, streamlined, often mucilaginous covering, lubricates, slow desiccation, productivity can be very high, many leak carbohydrates: soup for organisms. Some sea urchins can absorb organic molecules via skin. Seaweeds attached to seafloor at depth >250m into disphotic zone to absorb low light and transfer energy to chlorophyll photosynthesis: accessory pigments mask underlying chlorophyll. Allow growth near bottom of euphotic zone. Most large rapid growth rates 50cm/day.