Docstoc

Energy Flow Through an Ecosystem(5)

Document Sample
Energy Flow Through an Ecosystem(5) Powered By Docstoc
					 Energy Flow
 Through an
  Ecosystem
Food Chains, Food Webs,
    Energy Pyramids




   Created by C. Massengale. Revised by K. Slater 2008


                                                         1
             •Begins with the
             SUN
             •Photosynthesis


6CO2 + 6H2O + sunlight & chlorophyll
        C6H12O6 + 6O2


                                       2
Consumers that eat producers
       to get energy:
•Are first order (1 st)   or
primary consumers
 –Are herbivores (plant-eaters)


                                  3
        Trophic Levels
Each Level In A Food Chain or Food
 Web is called a Trophic Level.
Producers
  Always The First Trophic Level
  How Energy Enters The System
Herbivores
  Second Trophic Level
  Called “first order consumers”

                                     4
A Consumer that Eats Another
    Consumer for Energy:
     •Is in the third trophic
     level
     •Called a secondary or
     2nd order consumer
       –May be a carnivore or a
       omnivore
       –May be a predator
       –May be a scavenger
                                  5
  A consumer that eats a
consumer that already ate a
        consumer:
   •Is in the fourth trophic level
   •Called a 3rd order or
   tertiary consumer
     –May be a carnivore    or a
     omnivore, detritivore, or
     predator

                                     6
Most (≈90%) of
   the energy is
lost as heat, but
  some energy is
 stored and can
   passed on to
      another
     consumer.

                    7
Some (≈10%) of
 the energy the
    secondary
  consumer gets
from the primary
consumer is used
by the secondary
    consumer.
                   8
 The transfer of energy from
the sun to producer to primary
consumer then to higher order
 consumers can be shown in a
        FOOD CHAIN.




                                 9
Food Chains Show Available Energy




                                    10
 Another way
of showing the
  transfer of
 energy in an
 ecosystem is
      the
    ENERGY
   PYRAMID
                 11
12
Trophic Levels
     •Amount of available
     energy decreases for
     higher trophic levels
     • It takes a large number
     of producers to support a
     small number of primary
     consumers
     • It takes a large number
     of producers to support a
     small number of primary
     consumers


                                 13
Food Webs:

     •Are
     interconnected
     food chains
     • They show the
     feeding
     relationships in
     an ecosystem


                        14
How Many Chains are in
     this web?




                         15
Identify the Producers, Consumers, &
            Decomposers:
                                   Count the
                                     Food
                                    Chains!




                                               16
Build your own food web:
http://www.gould.edu.au/foodwebs/kids_web.htm

The Habitable Planet:
  http://www.learner.org/courses/envsci/interactiv
  es/ecology/index.php
Practice Time…
  Fill out the practice
   sheet provided,
   indicating:
   –Consumer level
   –Trophic level
   –Available Energy
                          18
  By this point, you should understand…
•What biology is            •Biotic vs. abiotic
•The 6 characteristics of   •Autotrophs vs.
living things               heterotrophs
•What cells are             •Photosynthesis
•The 4 needs of living      •Producers vs. consumers
things                      •5 types of consumers:
•Homeostasis                carnivores, herbivores,
•What ecology is            omnivores, decomposers,
•The 5 levels of            detritivores
                            • Food chain vs. food web
organization in ecology:
organism, population,       • Trophic levels
community, ecosystem,
biosphere
                            • Energy loss through
                            trophic levels

                                                        19
Consumers that eat producers
     & other consumers

               Are called
               omnivores
               Omnivores
               eat plants
                  and
                animals
                               20
 Consumers that hunt &
kill other consumers are
    called predators.
  The animals that are
   hunted & killed are
       called prey.



                           21
  Consumers that eat
 other dead consumers
are called scavengers
                        22
More Food Chains




                   23
24

				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:38
posted:7/14/2011
language:English
pages:24
Lingjuan Ma Lingjuan Ma
About