Ecology Terms Ecology = the study of the interactions between living organisms, and between living organisms and their environment

Ecology Terms Environment = the area in which an organism is found

Ecology Terms Community = populations of different species that live in the same area

Ecology Terms Ecosystem = Both the living organisms and the nonliving parts of an environment

Ecology is the study of relationships between organisms and between organisms and their environments

An ecosystem is a self sustaining group of organisms and their surrounding environment

Structure of the biosphere Hierarchy Species – reproductive group Population – members of a single species that live in a given area Community – assemblage of interacting species in a given area Biome – a region defined by its weather patterns (e.g. rainforest, desert) Ecosystem – a community of animals, plants, microbes, etc, together with the physical environment that supports it Biosphere – Planet (Earth)

Group of plants and animals = Earth = Group of plants and animals = Temperate Forest = Plants, animals, rocks, dirt, microbes = A Fox = The Students in this Classroom = Fig. 1

Two parts to an Ecosystem:. Biotic or living factors: Two parts to an Ecosystem: Biotic or living factors: Abiotic or non-living factors: Bacteria, fungi, plants, animals, protists Sunlight, elevation, temperature, water pressure, soil type

Factors affecting a population Biotic factors are the living influences on a population These include the living things that a population depends on for food and shelter They also include the living things that depend on the population, such as predators and competitors

Factors affecting a population Abiotic factors are the nonliving influences on a population These include things like temperature, precipitation, soil quality and the amount of light

Six major biomes Taiga Deciduous forest Tropical rain forest Desert Tundra Grassland Biomes are defined by their abiotic factors Use a biome from the left and define it using its abiotic factors

The Niche Niche = all of the conditions that a population needs to survive and the way in which the organism deals with those conditions A population’s niche includes: What does a population eat and how/when does it eat? Which organisms feed on the population? When and how does the population reproduce? Where does the population spend its time in the environment? How does the population obtain water? How does the population deal with changes in temperature and climate? Et cetera…

Energy in ecosystems or The Productivity is: The number and types of species that can live in an ecosystem. This depends on the amount of energy, space and resources (building materials) available in the ecosystem.

Types of Organisms: 1. Producers or Autotrophs include plants and some bacteria. They make their own food. They use energy from the sun and store it in macromolecules using the process photosynthesis. They store all the necessary energy and make all the nutrients for an ecosystem

Types of Organisms: 2. Consumers or Heterotrophs include all other organisms. They can’t make their own food so they need to consume other organisms for energy.

Types of consumers: Herbivores: plant eaters Omnivores: eat plants and meat Carnivores: meat eaters Decomposers: breaks down dead things. (Fungi and bacteria)

Trophic levels (troph = food): Refers to a group of organisms whose energy sources are the same number of steps away from the producers.

Trophic Relationships Draw the Energy Transfer below Primary Producers are Autotrophs harvest sunlight Heterotrophs are Consumers eat organic matter Place the type of energy on the arrows

The primary source of energy in an ecosystem is the sun The primary source of energy in an ecosystem is the sun. Energy moves through an ecosystem when one organism eats another.

Example: Upwelling- brings up minerals an nutrients Phytoplankton (autotroph) use these materials with sunlight to create energy to live Zooplankton eat the phytoplankton to live These are eaten by small fish, then big fish and on up to you Example: La Nina El Nino Fig. 2

Most animals feed at more than one trophic level and eat many different species. There is a loss of energy at each higher trophic level in an ecosystem. On average 90% of the energy is lost with each trophic level.

Productivity Pyramid Autotroph – plants & microbes Photosynthesis or chemosynthesis Produce organic matter from inorganic C sources Heterotroph – utilize the energy created by plants to gain energy Herbivores - ~ 20% Carnivores - ~ 0.2% (not very efficient at converting food to biomass!)

An energy pyramid shows how the total amount of energy in each trophic level compares with the next. The lowest trophic levels contain the most energy, the top trophic levels contain the least energy.