Ecosystems Part 2 Food Chains, Food Webs, and Energy
Autotrophs Organisms that use the energy in sunlight to convert water and carbon dioxide into Glucose (food) Also called Producers because they produce all of the food that heterotrophs use Without autotrophs, there would be no life on this planet Ex. Plants and Algae
AUTOTROPHS Chemotrophs Autotrophs that get their energy from inorganic substances, such as salt or sulfur Live deep down in the ocean where there is no sunlight Ex. Bacteria and Deep Sea Worms
HETEROTROPHS Organisms that do not make their own food Also called consumer because they consume other organisms in order to live Ex. Rabbits, Deer, Mushrooms
TYPES OF HETEROTROPHS 1. Scavengers/Detritivores feed on the tissue of dead organisms (both plans and animals) Ex. Vultures, Crows, and Shrimp
TYPES OF HETEROTROPHS 2. Herbivores eat ONLY plants Ex. Cows, Elephants, Giraffes
TYPES OF HETEROTROPHS 3. Carnivores eat ONLY meat Ex. Lions, Tigers, Sharks
TYPES OF HETEROTROPHS 4. Omnivores eat BOTH plants and animals Ex. Bears and Humans
TYPES OF HETEROTROPHS 5. Decomposers absorb any dead material and break it down into simple nutrients or fertilizers Ex. Bacteria and Mushrooms
Energy flows through ecosystems sun secondary consumers (carnivores) loss of energy primary consumers (herbivores) loss of energy producers (plants)
Food chains Trophic levels feeding relationships start with energy from the sun captured by plants 1 st level of all food chains food chains usually go up only 4 or 5 levels inefficiency of energy transfer all levels connect to decomposers Level 4 Tertiary consumer top carnivore Level 3 Secondary consumer Level 2 Primary consumer Level 1 Producer Decomposers carnivore heterotrophs herbivore autotrophs Bacteria sun Fungi
Inefficiency of energy transfer sun Loss of energy between levels of food chain To where is the energy lost? The cost of living! 17% growth only this energy moves on to the next level in the food chain 33% cellular respiration 50% waste (feces) energy lost to daily living
Organisms eat more the JUST one organism Food Web When more organism are involved it is know as a FOOD WEB Food webs are more complex and involve lots of organisms
Notice that the direction the arrow points the arrow points in the direction of the energy transfer, NOT what ate what Food Web
Biomass The total mass of the organic matter at each trophic level is called biomass Biomass is just another term for potential energy energy that is to be eaten and used. The transfer of energy from one level to another is very inefficient (10% Law)
Biomass
Ecological Pyramid An ecological pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem Shows the relative amounts of energy or matter contained at each trophic level The Pyramid shows which level has the most energy and the highest number of organisms
Ecological Pyramid
Biomagnification Increase in the concentration of a pollutant as it passes from one trophic level to the next Small amount in environment Large concentration at top of food chain
Ex. Biomagnification Water Phytoplankton Zooplankton Small fish Large fish Top Predator: Human, osprey, eagle, otter highest amount of toxic chemical http://www.dc.peachnet.edu/~ccarter/millerlec-12/sld053.htm
Impacts on Wildlife Loons diet of fish Decrease in chicks in areas of high mercury Large concentration of mercury in eggs Great Egrets study in Everglades indicates behavior of juveniles is effected Deformities in developing animals http://www.usgs.gov/themes/factsheet/146-00/
Fish Advisories 13 states have state wide advisories for fish from rivers and lakes 40 states have advisories on selected bodies of water Parts of Eastern Coast and Gulf of Mexico have advisories
Origins of the term Mad as a Hatter Mercury is a compound that was used to soften fur in the making of felt hats. Phrase Mad as a Hatter, from Alice in Wonderland -- refers to the toxic effect of mercury on the central nervous system. Hat makers had mental effects and "hatter's shakes".