Environments and Primary Productivity

Environments

Pelagic……the water Neritic – over continental shelf Oceanic

Epipelagic: down to 200 m Mesopelagic: 200-1000 m Bathypelagic: 1000-4000 m

Benthic…..the bottom

200 m

Neritic

1000 m

4000 m

200 m

Oceanic

Epipelagic

Mesopelagic

Bathypelagic

Light zones in ocean

Photic Light for photosynthesis Usually 0-100 m

Aphotic Without light Deeper than 1000 m

Benthic Environment

Similar zones as pelagic Omit details and new names

Making a living in the ocean

Primary productivity, respiration, decomposition

Depth zone differences

Differences between “climate” zones

Food chains and food webs

Primary productivity

Photosynthesiscarbon dioxide + water

sugar + oxygen

Chemosynthesishydrogen sulfide + water + oxygen + carbon dioxide

sugar + sulfuric acid

Primary productivity: rate at which biomass is produced by photosynthesis or chemosynthesis

Respiration and decay

Basically the opposite of photosynthesis

Releases nutrients back into the ocean

Uses oxygen (consider other sources of oxygen to the ocean)

Oxygen with depth (red)Nutrients with depth ( green)

Relate pattern to photosynthesis, respiration, decay and other processes

Example of primary producers

Algae Diatoms Coccolithophores Dinoflagellates

Basis of food webs and ecosystems

Variations in productivity verses latitude Photic zone important for photosynthesis

Some areas of ocean are light limited, some are nutrient limited, some are both

Pictures can tell the story of relationships Polar region Equatorial region Temperate region of ocean

Global ocean productivity: What causes this pattern?

Food webs and chains

Efficiency of energy transfer:Relate to number of trophic levels

Upwelling region

Coastal region

Open ocean