DIVERSITY & PRODUCTIVITY OF OCEAN LIFE
Classification is a way of organizing living things
Things that live in the ocean are called marine organism
Marine organisms can be classified according to where they live and how they move.
Classification of Marine Organisms
Plankton
Plankton include all organisms—algae, animals, and bacteria—that drift with ocean currents.
Nekton
Nekton include all animals capable of moving independently of the ocean currents, by swimming or other means of propulsion.
Pair share: name 2 types of animals, other than what is shown here, that would be considered nekton.
Benthos
Benthos describes organisms living on or in the ocean bottom.
Pair share: name 2 types of animals, other than what is shown here, that would be considered benthos.
Three factors are used to divide the ocean into distinct marine life zones: the availability of
sunlight the distance from
shore the water depth.
Marine Life Zones
Distance from Shore
• Intertidal zone is the strip of land where the land & ocean meet & overlap the zone between high and low tides.• Neritic zone is the marine-life zone that extends from
the low-tide line out to the shelf break.
• Oceanic zone is the marine-life zone beyond the continental shelf.
Marine Life Zones
Pair share: which zone do you think is the largest?
Water Depth
• Pelagic zone - open zone of any depth. Animals in this zone swim or float freely.
• Photic zone – 0-200m, upper part of the ocean into which sunlight penetrates.
• Benthic zone - 200-1,500 m deep, dimly lit.
• Abyssal zone – below 1,500 m, high pressures, low temperatures, low oxygen, few nutrients, and no sunlight.
Hydrothermal Vents
• At some vents, water temperatures of 100oC or
higher support communities of organisms found nowhere else in the world.
Productivity is the amount of food/ energy produced by plants, algae, and bacteria
Productivity varies in different parts of the ocean depending upon the availability of sunlight and nutrients.
Oceanic Productivity
Polar Oceans: the lack of solar energy limits productivity Tropical Oceans: the lack of nutrients limits productivity. Temperate Oceans: a combination of sunlight &
nutrients allows these regions to be more productive.
Comparing Productivity
Pair share: how does productivity off the coast of CA compare to the mid-Pacific?
WHITE BOARD REVIEW
1. Name the 3 classifications of marine life.
2. What are the 3 factors used to divide marine life zones?
3. Name 2 factors that limit ocean productivity.