3-1 What is Ecology?Interactions and InterdependenceEcology - _______________________________________________________________________________________________________________________________________biosphere - ______________________________________________________________________________________________________________________________________Levels of Organization• To understand relationships within the biosphere ecologists ask questions about events and organisms that range in complexity from single individuals to the entire biosphere• Studies can focus on…Species - ________________________________________________________________________________________________________________________________________Populations - ____________________________________________________________________________________________________________________________________________________________________________________________________________Communities - ___________________________________________________________________________________________________________________________________Ecosystem - _____________________________________________________________________________________________________________________________________
________________________________________________________________________Biome - _________________________________________________________________________________________________________________________________________________________________________________________________________________• The largest area of study would be the actual study of the biosphere itself
Ecological Methods• Regardless of the tools they use, scientists conduct modern ecological research using 3 basic approaches:1.2.3.Name ____________________________________ Date _________________ Per _____ 3-1 Section Review1. List the six different levels of organization that ecologists study, in order from smallest to largest.2. Describe the three basic methods of ecological research.3. Identify two ways in which you interact with each of the three parts of the biosphere— land, water, and air—every day.
4. Suppose you wanted to know if the water in a certain stream is safe to drink. Which ecological method(s) would you choose, and why? 3 – 2 Energy Flow• The flow of energy through an ecosystem is one of the most important factors that determines the systems capacity to sustain lifeProducers• _______________________ is the main energy source for life on Earth• Some types of organisms rely on the energy stored in organic chemical compoundsProducers (autotrophs) - ____________________________________________________________________________________________________________________________ex.)Energy From the SunPhotosynthesis - __________________________________________________________________________________________________________________________________
Life Without Light• Some autotrophs rely on energy within the chemical bonds of inorganic molecules such as hydrogen sulfideChemosynthesis - _________________________________________________________________________________________________________________________________
Consumers• Many organisms cannot harness energy directly from their environment like autotrophs doConsumers (heterotrophs) - _________________________________________________________________________________________________________________________________________________________________________________________________• There are many kinds of heterotrophsHerbivores - _____________________________________________________________Carnivores - _____________________________________________________________Detritivores - ____________________________________________________________________________________________________________________________________Decomposers - ___________________________________________________________Feeding Relationships• Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers)Food ChainsFood chain - _____________________________________________________________________________________________________________________________________
• In most ecosystems, feeding relationships are more complex than they can be shown in a food chainFood Webs - _____________________________________________________________________________________________________________________________________________________________________________________________________________
Trophic Levels - __________________________________________________________________________________________________________________________________1st - ____________________________________________________2nd – 3rd or higher - ________________________________________• Each consumer depends on the trophic level below it for energyEcological PyramidsEcological Pyramid – a diagram that shows the relative amounts of energy or mattercontained within each trophic level in a food chain or food web• There are 3 types of ecological pyramids1. Energy Pyramid - _______________________________________________________________________________________________________________________________• Only about ________ of the energy available within one trophic level is transferred to organisms at the next trophic level2. Biomass Pyramid - ______________________________________________________________________________________________________________________________
biomass - ______________________________________________________________________________________________________________________________________3. Pyramid of Numbers - ___________________________________________________________________________________________________________________________• Note: Pyramid of numbers may not always be pyramid shaped
Name ______________________________ Date _____________________ Per _______ 3 – 2 Section Review1. What are the two main forms of energy that power living systems?2. Briefly describe the flow of energy among organisms in an ecosystem.3. What proportion of energy is transferred from one trophic level to the next in an ecosystem?4. Show the following as a food chain: omnivore, autotroph, herbivore.5. Draw an energy pyramid for a five-step food chain. If 100 percent of the energy is available at the first trophic level, what percentage of the total energy is available at the highest trophic level?
3 – 3 Cycles of Matter• Energy is crucial to an Ecosystem, but organisms need more than that to survive• They also need o o o o o oRecycling in the Biosphere• unlike the one way flow of energy, matter is recycled within and between ecosystemsThe Water CycleEvaporation - ____________________________________________________________________________________________________________________________________transpiration - ____________________________________________________________________________________________________________________________________________________________________________________________________________
Nutrient CyclesNutrients - ______________________________________________________________________________________________________________________________________• Every living organism needs nutrients to grow and carry out essential life functions. Like water; nutrients are passed between organisms and the environment through cyclesThe Carbon Cycle• There are four different kinds of processes involved in the carbon cycle: 1. biological processes, such as photosynthesis, respiration, and decomposition of plants and animals; 2. geochemical processes, such as the release of carbon dioxide (CO2) gas to the atmosphere by volcanoes; 3. mixed biogeochemical processes, such as the burial of carbon rich remains of organisms and their conversion into coal and petroleum (fossil fuels) by the pressure of the overlying earth; and 4. human activity, including mining, the burning of fossil fuels, and the cutting and burning of forests.
The Nitrogen Cycle• All organisms require nitrogen to make amino acids, which in turn are used to build _________________________• Many different forms of nitrogen occur naturally in the biosphere• Although nitrogen gas is the most abundant form of nitrogen on Earth, only certain types of bacteria can use this form directlyNitrogen fixation - ________________________________________________________________________________________________________________________________
The Phosphorus Cycle• Phosphorus is essential to living organisms because it forms part of important life sustaining molecules such as ________________________• Unlike Carbon, oxygen and nitrogen, phosphorus does not enter the atmosphere• Phosphorus remains mostly on land in rock and soil minerals, and in ocean sediments• As the rocks and sediments gradually wear down, phosphate is released• Plants absorb phosphate then move to the rest of the ecosystem
Nutrient Limitation• Ecologists are often interested in the primary productivityPrimary productivity - _____________________________________________________________________________________________________________________________• If a nutrient is in short supply, it will limit an organisms growthLimiting nutrient - ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Name _________________________________ Date _____________________ Per ____ 3 – 3 Section Review