1. The Ocean’s primary Productivity
Marine Biomass

3. Phytoplankton bloom

4. Environment
Ecosystem – composed of living organisms and their nonliving environment
Biotic – living organisms
Abiotic – physical characteristics

5. Habitat
An organisms habitat is where it lives

6. Niche: An organism’s environmental role
An organisms niche is the role the organism plays in its community
An organisms niche is determined by a variety of biotic and abiotic factors acting together on the organism.

7. Environmental Factors
Maintaining Homeostasis
An organisms ability to maintain a stable internal environment regardless of the external environment
Homeostasis and the distribution of marine organisms
Optimal range allows for an organism to thrive and reproduce (sunlight, nutrients)
Zones of stress are areas above or below the optimal range
The organism expends more energy maintaining homeostasis
Less energy is available for reproduction
Zones of intolerance are areas beyond the optimal range where the organism cannot survive

8. Environmental factors continued
Physical environment
Sunlight
Temperature
Salinity
Pressure
Metabolic requirements
Metabolic wastes

9. Sunlight Sunlight penetration
less than 1 meter in coastal waters
as much as 200 meters in tropical waters
Photosynthesis directly or indirectly provides energy to nearly all forms of life on earth
Phytoplankton – the largest group of photosynthetic organisms in marine environments
Phytoplankton are the primary sources of nutrients and energy for marine animals

10. Temperature Temperature influences the distribution of organisms
Ectotherms – obtain body heat from surroundings
Endotherms – maintains a constant body temperature
Most organisms can tolerate only a specific range of environmental factors
Temperatures above or below the critical range disrupt metabolism resulting in:
Decreased ability to reproduce, injury, or death

11. Salinity
Salinity is a measure of the concentration of dissolved inorganic salts in the water
In order to maintain homeostasis all organisms must maintain a proper balance of water and solutes in their bodies
The process of osmosis is vital to cells
If a cell loses too much water it will become dehydrated and die
If a cell takes in too much water it will swell and burst

12. Pressure
The pressure of the water affects organisms that inhabit the deep regions of the seas
Some animals must have special adaptations that allow them to survive at great depths to avoid compression (diving) and decompression (surfacing)

13. Metabolic Requirements
The availability of nutrients influences the distribution of organisms in the marine environment
Nutrient – all of the organic and inorganic materials that an organism needs to reproduce

14. Metabolic requirements continued
Limiting nutrients (ex. nitrogen, phosphorus)
Anaerobic organisms – survive in the absence of oxygen
Aerobic organisms – require oxygen
Eutrophication –nutrient enrichment
Algal bloom – population explosion of photosynthetic plankton

15. Metabolic wastes
Waste products are usually removed from the environment by organisms or broken down by bacteria
Waste products can accumulate to toxic levels and prohibit growth

16. Environmental factors continued Biological Environment
Biological environment - all of the different species and the interactions an organism comes in contact with
Relationships
Competition
Predator-Prey relationships
Symbiosis: Living together

17. Competition
Two or more species in the same habitat that have the same requirements for resources that are limited in supply are in competition

18. Predator-prey relationships
Keystone predator (keystone species) – An animal in a community that makes it possible for other species to live there
Ochre seastar
REMOVAL OF A CERTAIN SPECIES OF STARFISH CAUSED A RAPID GROWTH IN THE NUMBERS AND BIOMASS OF THE MUSSEL UPON WHICH THE SEASTAR FED

20. Symbiosis: Living together
Symbiosis – any prolonged association or living together of two or more organisms of different species
Mutualism
Both organisms benefit
Commensalism
One organism benefits, the other is neither harmed nor benefited
Parasitism
One organism benefits, the other is harmed

21. Distribution of Marine Communities
Pelagic Division – the water column
Benthic Division – the ocean bottom

22. Ecosystems: Basic units of the Biosphere
Producers – organisms that contain pigments like chlorophyll that capture the sun’s energy
Photosynthesis – the process by which energy of sunlight is used to form glucose
Chemosynthesis – the process by which energy from chemical reactions is used to construct organic glucose

24. Producers Autotrophs – organisms able to produce their own food
Chemoautotrophs – organisms that use energy from inorganic chemicals to produce their own food

25. Measuring Primary Productivity
Grams of carbon per square meter of surface area per year
gC/m2/yr

26. Ecosystems: Basic units of the Biosphere continued
Trophic Levels