Chapter 3:Ecology Introduction

What is Ecology? The Biosphere Life on a global scale All life on Earth and all parts of Earth in which life exists Extends 8 Kilometers above the surface and 11 kilometers below the surface of Earth Largest level of organization Ecology The study of interactions between organisms and the environment Greek for “House”. Greek word is oikos July 22, 2012Footer text here2

Levels of Organization July 22, 2012Footer text here3 Individuals One single organism Population Group of Individuals (Species) Community Different populations brought together Ecosystem Populations mixed with the physical environment Biome Ecosystems with similar characteristics Biosphere All biomes brought together. The “living planet”

What are biotic and abiotic factors? Biotic Factors The living part of the environment Ex: Plants Animals Bacteria Abiotic Factors Non living part of the environment Ex: Water Dirt Sunlight Heat July 22, 2012Footer text here4

Chapter 3: Ecology Energy, Producers, and Consumers

Obtaining Energy Primary Producers Autotrophs Organism able to make their own food Generally done through the process of photosynthesis Organisms change sunlight, CO2 and water into oxygen and food Chemosynthesis Organisms that live in areas without sunlight use this process to make food Consumers Heterotrophs Organisms that obtain food by consuming or eating other organisms Categories Carnivores (kill and eat other animals) Scavengers (consume dead carcasses) Herbivores (consume plants) Omnivores (will eat plants and animals) Decomposers (Break down dead organic matter) Detritivores (Eat decomposers) July 22, 2012Footer text here6

Chapter 3: Ecology Energy Flow in Ecosystems

Food Chains and Food Webs Food Chain (pg. 63) Series of steps in an ecosystem Organisms transfer energy through different steps by either eating or being eaten Primary producers are always the bottom step of a food chain Food Web (pg. 65) Complex network of feeding relationships within an ecosystem Several organisms can feed on one animal or producer Organisms can all survive on more than one food source Creates a delicate balance however since many organisms have to rely on one species July 22, 2012Footer text here8

Ecological Pyramids Trophic Levels A step within a food chain or food web Primary producers are always the first level Ecological pyramid Shows the amount of energy or matter within each level of the food chain or web Pyramid of Energy Each level only stores a certain amount of energy in their tissue Shows the relative amount of energy being transferred at each level Typically only about 10% is transferred to the next level Pyramid of Biomass Biomass Grams of organic matter per unit area Relative amount of living tissue available to be consumed at each level Pyramid of Numbers Relative number of organisms at each level that can be consumed The higher up the level, the smaller the numbers July 22, 2012Footer text here9

Chapter 3: Ecology Cycles of Matter

Recycling in the Biosphere What are biogeochemical cycles? Process in which elements, chemical compounds, and other forms of matter are passed through the parts of the biosphere from different organisms Everything is recycled within the ecosystem and between them as well Biological processes Consist of any and all actions performed by living things Ex: breathing, eating, and moving Geological processes Consist of any movement coming from the Earth Ex: Volcanic eruptions, earthquakes, and rock formations Chemical processes Formation of clouds Precipitation Running water and lightning Human Activity Any action done by humans. All will affect these processes in some way July 22, 2012Footer text here11

The Water Cycle The process of water moving throughout the biosphere Step 1: Evaporation Groundwater or other water on the surface of the Earth and evaporates Water vapor is taken up into the sky Step 2: Condensation Water vapor is collected and condensed into tiny droplets These droplets form clouds Step 3: Precipitation The condensed water is released from the clouds in any form of rainfall Rainfall can become runoff or land into a groundwater source or ocean where the process will start over again July 22, 2012Footer text here12

The Nitrogen Cycle All organisms need some form of nitrogen Nitrogen gas is the most common form found on Earth Only bacteria can change nitrogen into useable forms for other organisms Nitrogen Fixation Process of converting nitrogen gas into other nitrogen compounds such as nitrates and ammonia for plants Denitrification Process of converting nitrates into nitrogen gas Performed by soil bacetria July 22, 2012Footer text here13

Nutrient Limitations What are limiting nutrients? These can consists of nutrients that are in low supply This causes primary producers to be unable to produce food July 22, 2012Footer text here14

Quiz Questions: Section 1 1. What is Ecology? Answer: Scientific study of interactions between organisms. Ecology also studies the interactions between organisms and their physical environment 2. What are biotic and abiotic factors? Answer: Biotic factors are any living organism within an environment. This includes plants and animals. Abiotic factors are the nonliving parts of the environment. This can include dirt, water, and temperature July 22, 2012Footer text here15

Quiz Questions: Section 2 1. What are primary producers? Answer: Also called autotrophs. These are the organisms that can make their own food. They do this through photosynthesis or chemosynthesis. They are the bottom level of the food chain 2. How do consumers obtain nutrients and energy? Answer: Consumers cannot make their own food. Also called heterotrophs, consumers must obtain energy by eating other organisms July 22, 2012Footer text here16

Quiz Questions: Section 3 1. How does energy flow through the ecosystem? Answer: Energy flows through the ecosystem in a one way stream. This means that either through a food chain or food web, organisms consume energy from a lower level. It also begins with a primary producer 2. What do the 3 types of ecological pyramids illustrate? Answer: The pyramid of energy shows us how much energy is being moved up through each trophic level. The pyramid of biomass shows us how much organic tissue is available at each trophic level. The pyramid of numbers shows us how many organisms are at each trophic level. July 22, 2012Footer text here17

Quiz Questions: Section 4 1. How does matter move through the biosphere? Answer: Matter is always recycled within the biosphere. This can happen within one ecosystem or between multiple ecosystems 2. How does water move through the biosphere? Answer: Water moves through the biosphere in 3 steps. Step 1 is Evaporation (explain evaporation.) Step 2 is Condensation (explain condensation). Step 3 is Precipitation (explain precipitation). 3. How does nutrient availability relate to the primary productivity of an ecosystem? Answer: Primary producers require certain nutrients in order to make food. If those nutrients are not in supply within the ecosystem, the producers can only make so much food at a certain time which can hinder the ecosystem July 22, 2012Footer text here18

Chapter 3: Ecology Quiz