How can abiotic factors affect plant and animal distributions in freshwater and
marine ecosystems?
➢ 1) Pollution ➢ 2) temperature ➢ 3) dissolved oxygen ➢ 4) phosphates➢ 5) ph➢ 6) turbidity➢ 7) upwelling
Pollution
Pollution is any harmful material that is released into the environment.
➢ It can be natural or a result of human activities.
➢Most pollution in the world’s oceans is found along the coastlines.
Direct and Indirect Pollution
Direct (from one source) examples of pollution include:➢ Landfill leaks➢ Industry dumping waste water➢ Oil spills➢ Sewage systems
Indirect (from many sources) examples of pollution include:➢ Oils leaks from cars and trucks on roads➢ Pesticides and fertilizers from lawns, farms, golf courses, ➢ animal waste from farms➢ runoff from city streets
Temperature
➢ temperature- warm water hold less dissolved oxygen than cold water. (The more dissolved oxygen there is the better for living organisms)
Dissolved OxygenThe amount of dissolved oxygen in the water may
depend on several factors:abiotic (non-living) factors: ➢ Colder, moving water holds more dissolved oxygen
biotic (living) factors:➢ living things consume dissolved oxygen in water➢ Too many dead organisms cause decomposers to
use up available oxygen
➢ Lack of oxygen kills the organisms that need it.➢ Dissolved oxygen levels should be 5 mg/L (or 5 ppm)
or greater
Phosphates
➢ Phosphates are substances occurring naturally in the soil which enhance plant growth.
➢ Phosphates can become a problem in water systems:
excess plant →decomposition → low oxygen levels
➢ Phosphate levels should be less than 10 μg/L
pH
➢pH scale0------------------------7-----------------------14Acids Neutral Bases
➢Acid rain, formed as a result of pollution, can affect pH.
➢Water pH should be in the range of 5 to 8.5, if not plant or animal life may begin to die.
Turbidity➢ Turbidity is the amount of undissolved solids suspended
in the water (cloudy water) turbidity
↓
blocks sunlight ↓
less photosynthesis
↓
less O2 produced ↓
organisms begin to die
Upwelling
➢Upwelling is the vertical motion of water in the ocean (subsurface water of lower temperature and greater density moves toward the surface of the ocean)
upwelling →nutrients→ plant life → attracts animal life
The End
