The Biosphere

1
Chapter 3

• The Biosphere

2
What is Ecology?

• Interactions Interdependence
• Ecology is the study of interactions among
  organisms and between organisms and their
  environment.
• All the earths organisms live in the biosphere
  (land, water, air, atmosphere).

3
Levels of Organization

• individual
• population group of individuals of the same
  species that live in the same area
• community different populations that live
  together in a defined area
• ecosystem all the organisms that live in a
  particular place with their nonliving
• environment
• biome ecosystems that have the same climate,
  soil, and dominate communities
• biosphere all the parts of the planet where life
  exists the largest level that contains all the
  others

4
Levels of Organization
5
Energy Flow

• All organisms need to get energy from their
  environment in order to survive.

6
Producers

• sunlight is the major source of energy for life
  on earth
• only plants, some algae, and certain bacteria are
  producers
• autotrophs (producers) capture energy from
  sunlight or chemicals and use the energy to
  produce food

7
Autotrophs

• photosynthesis the process of autotrophs using
  light energy to make food
• chemosynthesis the process of autotrophs using
  chemical energy to make carbohydrates (food)

8
Consumers

• heterotrophs (consumers) organisms that rely on
  other organisms for their food

9
Heterotrophs

• herbivore eats only plants
• carnivore eats only animals
• omnivore eats plants and animals
• detritivore feeds on dead organisms
• decomposer breaks down dead organisms

10
Feeding Relationships

• energy flows through an ecosystem in one
  direction
• sun / inorganic compounds --gt autotrophs --gt
  heterotrophs

11
Feeding Relationships

• food chain series of steps where organisms
  transfer energy by eating and being eaten
• food web links together all food chains within
  an ecosystem

12
Trophic Levels

• each step in a food chain or web is called a
  trophic level
• producers make up the first trophic level
• consumers make up the second, third, and higher
  trophic levels
• each consumer depends on the trophic level below
  it for energy

13
Ecological Pyramids

• diagrams that show the relative amounts of energy
  or matter contained within each trophic level in
  a food chain or web

14
Energy Pyramid

• shows how much energy is available at each
  trophic level (only 10 of the energy is
  transferred up to the next level) organisms use
  much of the available energy for life processes

15
Biomass Pyramid

• shows the amount of living tissue at each trophic
  level amount of potential food

16
Pyramid of Numbers

• shows the number of organisms at each trophic
  level not necessarily pyramid shaped (ex. forest)

17
Cycles of Matter

• Energy moves through the biosphere in one
  direction. Matter is recycled within and between
  ecosystems. Biogeochemical cycles connect the
  biological, geological, and chemical aspects of
  the biosphere.

18
Water Cycle

• all living things require water to survive water
  moves between the atmosphere, oceans, and land
• evaporation the process by which water changes
  from a liquid form to atmospheric gas
• transpiration the
• process of water
• entering the
• atmosphere by
• evaporating from
• the leaves of plants

19
Nutrient Cycles

• Every living thing needs nutrients to build
  tissue and carry out essential life functions.
  Nutrients are passed between organisms and the
  environment.

20
Carbon Cycle

• carbon is the key ingredient of living tissue
• carbon passes
• through the
• environment by
• photosynthesis,
• decomposition,
• erosion, conversion
• of fossil fuels, mining,
• burning of forests, and
• many other processes

21
Nitrogen Cycle

• nitrogen is required
• to make amino acids,
• the building blocks of
• proteins
• nitrogen is found in
• different forms in the
• atmosphere, ammonia,
• fertilizers, and other
• things
• nitrogen fixation certain bacteria convert
  nitrogen gas into ammonia
• denitrification bacteria convert nitrates into
  nitrogen gas

22
Phosphorous Cycle

• phosphorous is
• required to form
• DNA and RNA
• phosphorous is
• found in rock and
• soil minerals and
• ocean sediments
• phosphorous is
• released as rocks and sediments wear down
• phosphorous then moves through the ecosystem