1. The Biosphere

2. Chapter 3 Outline 3-1: What is Ecology? 3-2: Energy Flow
Interactions and Interdependence
Levels of Organization
Ecological Methods
3-2: Energy Flow
Producers
Consumers
Feeding Relationships
Ecological Pyramids

3. Chapter 3 Outline 3-3: Cycles of Matter Recycling in the Biosphere
The Water Cycle
Nutrient Cycle
Carbon Cycle
Nitrogen Cycle
Phosphorus Cycle
Nutrient Limitation

4. Interactions and Interdependence
Ecology: The study of interactions among organisms and between organisms and their environment (or Surroundings)
Biosphere: The combined portions of the planet in which all life exists including land, water, and atmosphere.

5. Levels of Organization
To understand relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual to the entire biosphere.

6. Levels of Organization
Levels that ecologists study interaction:
Species: groups of organisms that can breed to produce fertile offspring
Population: groups of individuals that belong to the same species and live in the same area.
Community: groups of populations in an area
Ecosystem: collection of all the organisms that live in an area AND all the nonliving components.

7. Levels of Organization
Larger systems are also studied  Biomes
Biomes: groups of ecosystems that have the same climate and similar dominant communities.

8. Ecological Methods Three basic approaches to study ecology: Observing
Experimenting
Modeling
Scientists make models to understand complex phenomena (ex. Global Warming)
Many Models are math formulas

9. Producers Sunlight is the main energy source for life on Earth
Only a few organisms can use chemical compounds as their energy source
Autotrophs: organisms that use energy from the environment to produce their own food.
Ex. All plants, some bacteria, and some algae.

10. Producers Autotrophs are also called producers.
Plants make their own food through Photosynthesis
Organisms that produce their own food from chemicals are called chemoautotrophs and use the process of chemosynthesis. (Bacteria)

11. Consumers
Organisms (animal, fungi, many bacteria) that annot make their own food must eat other organisms that can!
Heterotrophs: organisms that rely on organisms for energy and food.

12. Consumers Types of consumers: Herbivores Carnivores Omnivores
Detritivores – feed on dead plant and animal matter (Detritus)
Decomposers – break down organic matter.

13. Feeding Relationships
Energy flows through an ecosystem in one direction:
Sun  autotrophs (producers)  heterotrophs (consumers)
The energy stored by producers is passed through an ecosystem through a food chain: a series of steps in which organisms transfer energy by eating and being eaten.
Ex. In Marine food chains, producers are algae, eaten by plankton, eaten by fish, etc.

14. Feeding Relationships
Food Webs: links many food chains together
Complex feeding network in an ecosystem

15. Feeding Relationship Trophic Levels
Each step in a food chain or Food Web
EX. Producer  1st Level

16. Ecological Pyramids
Ecological pyramid: a diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or web.

17. Ecological Pyramid Three types of pyramids in ecology: Energy pyramid
Only about 10% of the energy available within one trophic level is transferred to organisms at the nest trophic level. (Organisms use most energy for respiration, movement, reproduction, etc.)

18. Three Types of Pyramids
Biomass Pyramid:
Biomass: Total amount of living tissue within a trophic level.
Shows the amount of potential food available for each trophic level.
Pyramid of Numbers
Shows the number of individual organisms at each trophic level.

19. Three types of Pyramids
Energy Pyramid
Shows the relative amount of
energy available at each trophic
level. Organisms use about 10
percent of this
energy for
life processes.
The rest is lost
as heat.
Pyramid of Numbers
Shows the relative
number of individual
organisms at each
trophic level.
Biomass Pyramid
Represents the amount of
living organic matter at each
trophic level. Typically, the
greatest biomass is at the
base of the pyramid.

20. Recycling in the biosphere
In addition to energy, organisms need water, minerals, and other compounds in order to live
Unlike energy that flows one-way through an ecosystem, matter is recycled within and between ecosystems.
Elements, chemical compounds, and other forms of matter are passed from one part of the biosphere to another through biogeochemical cycles.
Matter cycles within biosphere because it is not used up, just converted from on form to another.

21. The Water Cycle
Water moves between the ocean, atmosphere, and land. Water enters the atmosphere as water vapor (a gas).
Evaporation: the process by which water changed from a liquid to an atmospheric gas
Transpiration: water lost into the atmosphere from a plant.
After evaporation, the water vapor condenses into droplets to form clouds. When the droplets become large and dense enough, the water returns to the Earth in the form of Precipitation.

22. The Water Cycle

23. Nutrient Cycles
Nutrients: All the chemical substances that an organism needs to sustain life
Every living organism needs nutrients to build tissues and carry out essential life functions. Like water, nutrients are passed between organisms and the environment through biogeochemical cycles.

24. Nutrient Cycles
Three important nutrient cycles: carbon cycle, nitrogen cycle, phosphorus cycle.

25. The Carbon Cycle
Carbon is important because it is a component of skeletons, it is the atmosphere, and is the building block of many macromolecules.
Four main types of processes move carbon through its cycle:
Photosynthesis and respiration
Erosion and Volcanic activity
Decomposition
Human activities (ex. Burning Fossil Fuels)

26. The Carbon Cycle
CO2 in
Atmosphere
CO2 in Ocean

27. The Nitrogen Cycle
All Organisms require nitrogen to make amino acids (which make proteins).
Nitrogen gas is in the atmosphere, but only some types of bacteria can break it down to be used by plants and animals
Nitrogen fixation – the process of converting nitrogen gas into ammonia
(after this other bacteria convert ammonia into nitrates to be absorbed by plant roots)

28. Nitrogen Cycle
When organisms die, decomposers return nitrogen to the soil as ammonia. Other soil bacteria convert it back to nitrogen gas in a process called denitrification.

29. Nitrogen Cycle
N2 in Atmosphere
NO3-
and NO2-
NH3

30. The Phosphorus Cycle
Phosphorus is essential to living things because it is used to build DNA and RNA.
It is not found in the atmosphere like carbon and nitrogen. Phosphorus is in rocks, soil and ocean sediments. It is released when rocks and sediments wear down.

31. The Phosphorus Cycle

32. Nutrient Limitation
Ecologists are interested in the primary productivity (the rate at which organic matter is created by producers)
Limited by available nutrients
Limiting nutrients – a single nutrient that is limiting growth in an ecosystem

33. Nutrient Limitation
Because of this farmers use fertilizers to boost productivity.
Fertilizers usually contain nitrogen, phosphorus, and potassium
When aquatic ecosystems receive runoff from fertilized fields, there is a boom of algae growth (producers).
Algal Bloom: a huge increase in the growth of algae.
If there are not enough consumers to eat this algae, it will cover the surface of the water and disrupt the ecosystem.