Warm Up 2/19-20Warm Up 2/19-20

1) Most ocean water is located in which zone?a. mixed zone c. surface zoneb. transition zone d. deep zone

2) Which ocean zone does sunlight penetrate?a. aphotic zone c. neritic zoneb. photic zone d. abyssal zone

3) Which of the following best describes the ocean bottom?a. quiet c. coldb. dark d. all of the above

Answers: 1) d. 2) b. 3) d.

Oceanic ProductivityOceanic Productivity

Chapter 15, Section 3Chapter 15, Section 3

Primary ProductivityPrimary ProductivityPrimary Productivity –Primary Productivity – the production of the production of organic compounds from inorganic substances organic compounds from inorganic substances through photosynthesis or chemosynthesisthrough photosynthesis or chemosynthesisPhotosynthesis –Photosynthesis – the use of light energy to the use of light energy to convert water and carbon dioxide into energy-convert water and carbon dioxide into energy-rich glucose moleculesrich glucose moleculesChemosynthesis –Chemosynthesis – the process by which the process by which certain microorganisms create organic certain microorganisms create organic molecules from inorganic nutrients using molecules from inorganic nutrients using chemical energychemical energyTwo factors influence a region’s photosynthetic Two factors influence a region’s photosynthetic productivity: the availability of nutrients and the productivity: the availability of nutrients and the amount of solar radiation, or sunlightamount of solar radiation, or sunlight

PhotosynthesisPhotosynthesis

Concept CheckConcept Check

What factors influence a region’s What factors influence a region’s photosynthetic productivity?photosynthetic productivity?

Sunlight and nutrient availabilitySunlight and nutrient availability

Productivity in Polar OceansProductivity in Polar OceansPolar regions experience continuous darkness Polar regions experience continuous darkness for about three months of winter and continuous for about three months of winter and continuous illumination for about three months of during illumination for about three months of during summersummerProductivity of phytoplankton, mostly single-Productivity of phytoplankton, mostly single-celled algae, peaks in Maycelled algae, peaks in MayAs soon as the phytoplankton develop, As soon as the phytoplankton develop, zooplankton come in to eat themzooplankton come in to eat themIn summer, melting ice creates a low-salinity, In summer, melting ice creates a low-salinity, low-density region on the surface that will not low-density region on the surface that will not readily mix with the deeper waters; helping the readily mix with the deeper waters; helping the phytoplankton to continue producingphytoplankton to continue producingThe availability of solar energy is what limits The availability of solar energy is what limits photosynthetic productivity in polar areasphotosynthetic productivity in polar areas

Productivity in Polar OceansProductivity in Polar Oceans

Productivity in Tropical OceansProductivity in Tropical OceansProductivity is low in tropical regions of the Productivity is low in tropical regions of the open oceanopen oceanLight penetrates much deeper into tropical Light penetrates much deeper into tropical oceans than in temperate and polar watersoceans than in temperate and polar watersSolar energy is available year-roundSolar energy is available year-roundA permanent thermocline prevents mixing A permanent thermocline prevents mixing between surface waters and nutrient-rich between surface waters and nutrient-rich deeper waters; it is a barrier that cuts off deeper waters; it is a barrier that cuts off the supply of nutrients from deeper watersthe supply of nutrients from deeper watersProductivity in tropical regions is limited by Productivity in tropical regions is limited by the lack of nutrientsthe lack of nutrients

Water Layers in the TropicsWater Layers in the Tropics

Productivity in Temperate OceansProductivity in Temperate OceansIn temperate regions, which are found at mid-latitudes, In temperate regions, which are found at mid-latitudes, a combination of these two limiting factors, sunlight a combination of these two limiting factors, sunlight and nutrient supply, controls productivityand nutrient supply, controls productivityWinter: productivity is low, due to the low angle of the Winter: productivity is low, due to the low angle of the sun and shallower sunlight penetrationsun and shallower sunlight penetrationSpring: phytoplankton bloom due to an increase in Spring: phytoplankton bloom due to an increase in nutrients and sunlight, nutrient supply is in greater nutrients and sunlight, nutrient supply is in greater demand and limits productiondemand and limits productionSummer: nutrients depleted from spring “bloom” are Summer: nutrients depleted from spring “bloom” are not able to be replenished from deep waters due to a not able to be replenished from deep waters due to a sharp thermocline, phytoplankton population will sharp thermocline, phytoplankton population will remain lowremain lowFall: nutrients return to the surface, as the summer Fall: nutrients return to the surface, as the summer thermocline breaks down, and another “bloom” of thermocline breaks down, and another “bloom” of phytoplankton occurs (short-lived due to decreasing phytoplankton occurs (short-lived due to decreasing sunlight) sunlight)

Productivity in Temperate Productivity in Temperate OceansOceans

Comparing ProductivitiesComparing Productivities

Concept CheckConcept Check

What limits primary productivity in tropical What limits primary productivity in tropical oceans? Why?oceans? Why?

The availability of nutrients; solar energy is The availability of nutrients; solar energy is available year round but nutrient are available year round but nutrient are trapped in deeper waters because the trapped in deeper waters because the permanent thermocline prevents mixing permanent thermocline prevents mixing between surface water and deeper water.between surface water and deeper water.

Oceanic Feeding RelationshipsOceanic Feeding RelationshipsAs producers make food available to the consuming As producers make food available to the consuming animals of the ocean, energy passes from one animals of the ocean, energy passes from one feeding population to the nextfeeding population to the nextTrophic Level –Trophic Level – a nourishment level in a food chain; a nourishment level in a food chain; plant and algae → herbivores → carnivoresplant and algae → herbivores → carnivoresThe transfer of energy between The transfer of energy between trophic levelstrophic levels is very is very inefficientinefficientFood Chain –Food Chain – sequence of organisms through which sequence of organisms through which energy is transferred, starting with the primary energy is transferred, starting with the primary producerproducerFood Web –Food Web – a group of interrelated a group of interrelated food chainsfood chainsAnimals that feed through a food web rather than a Animals that feed through a food web rather than a food chain are more likely to survive because they food chain are more likely to survive because they have alternative foods to eat should one of their food have alternative foods to eat should one of their food sources diminish or disappearsources diminish or disappear

Ecosystem Energy FlowEcosystem Energy Flow

Food Chain Vs. Food WebFood Chain Vs. Food Web

Concept CheckConcept Check

What advantage do organisms in a food What advantage do organisms in a food web have over those in a food chain?web have over those in a food chain?

Organisms in a food web have alternative Organisms in a food web have alternative foods to eat if one of their food sources foods to eat if one of their food sources diminishes or disappears.diminishes or disappears.

Assignment (Due 2/21)Assignment (Due 2/21)

Read Chapter 15 (pg. 422-437)Read Chapter 15 (pg. 422-437)

Do the Chapter 15 Assessment #1-32 (pg. Do the Chapter 15 Assessment #1-32 (pg. 443-444)443-444)

Study for Chapter 15 Quiz!!!Study for Chapter 15 Quiz!!!

Cool DownCool Down

1)1) Describe the transfer efficiency between trophic Describe the transfer efficiency between trophic levels.levels.

Very inefficient; as little as 2%Very inefficient; as little as 2%

2)2) Explain why producers are always the first Explain why producers are always the first trophic level in a food chain or food web.trophic level in a food chain or food web.

Producers are organisms that are able to use Producers are organisms that are able to use light or chemical energy to produce glucose. light or chemical energy to produce glucose. Consumers cannot produce their own food and Consumers cannot produce their own food and rely on producers as a food source.rely on producers as a food source.

3)3) What is one thing you learned today that you What is one thing you learned today that you never knew? Explain.never knew? Explain.