Marine Ecology Marine Ecology

• AbioticAbiotic– Non-living part of the environmentNon-living part of the environment

• BioticBiotic– Living part of the environmentLiving part of the environment– interdependence of all organisms living in the interdependence of all organisms living in the

ocean, in shallow coastal waters, and on the ocean, in shallow coastal waters, and on the seashoreseashore

Marine Abiotic Factors Marine Abiotic Factors • water• salinity• light• pressure• temperature• dissolved gases• pH• tides• currents• waves• substratum• nutrient supply• exposure to air

Water Cycle Water Cycle

97 % of the water on earth is salt water in the ocean. Of the 3% of water that is fresh water, 2% is frozen in ice caps and only 1% is usable by organisms as liquid water or water vapor found in lakes, rivers, streams, ponds , in the ground water, and as vapor in the atmosphere

Unique Qualities of Pure Water Unique Qualities of Pure Water The Unique Nature of Pure Water Water is 775 times as dense as air at 0 o C Water is found on earth in three forms – liquid,

solid and gas Density – maximum density is at 4o C not at

freeing point of 0 o C and expands as it freezes so ice floats

The H20 molecule is polar and hydrogen bonding is present

Water is a polar molecule; one end is positively charged and the other is negatively charged

Cohesion of water molecules at the surface of a body of water (surface tension) is very high

Salt Water Features Salt Water Features

The oceans consist of (by mass):

• 96.5% water

• 3.0% sodium and chlorine ions (table salt, Na+ and Cl–)

• 0.5% other salts

Marine Environments Marine Environments

Marine Regions Marine Regions

Food Chain Food Chain • ProducerProducer• 11stst order Consumer or order Consumer or

HerbivoreHerbivore• 22ndnd order Consumer or 1 order Consumer or 1stst

order Carnivoreorder Carnivore• 33rdrd order Consumer or 2 order Consumer or 2ndnd

order Carnivoreorder Carnivore• 44thth order Consumer or 3 order Consumer or 3rdrd

order Carnivoreorder Carnivore• Decomposers – consume Decomposers – consume

dead and decaying matter dead and decaying matter as bacteria as bacteria

Marine Food Web Marine Food Web

Ecologic Pyramids Ecologic Pyramids

Ecological pyramid - a graph representing trophic level numbers within an ecosystem. The primary producer level is at the base of the pyramid with the consumer levels above.

• Numbers pyramid - compares the number of individuals in each trophic level. May be inverteddue to size of individuals

• Biomass pyramid - compares the total dry weight of the organisms in each trophic level.

• Energy pyramid - compares the total amount of energy available in each trophic level. This energy is usually measured in kilocalories.

Trophic Pyramids-MarineTrophic Pyramids-Marine

The 10% rule for Energy Pyramids

Carbon, Nitrogen & Phosphorus CyclesCarbon, Nitrogen & Phosphorus Cycles

Threats to Marine EcosystemsThreats to Marine Ecosystems• Oil spills and their ecological disasters• Marine dumping of wastes – plastic and

other wastes • Dredging Wastes• Overfishing • Ocean acidification reducing calcium

carbonate• Population displacement • Mangrove Destruction• Bycatch – marine wildlife unintentionally

caught as sea turtles, porpoises, albatross, crabs, starfish & fish

• Whaling is still a problem though strides are being make

Threats to Ocean Health Threats to Ocean Health • Marine Pollution • Habitat Destruction• Overfishing and Exploitation• Climate Change• Sea Temperature Rise • Ocean Acidification • Invasive Species • Ocean Dead Zones