Ecology The study of how living things interact with their environment

What are our goals for this topic? Develop a working content specific vocabulary for ecology Learn how different organisms interact with the living and non-living parts of their environment. Understand the different types of relationships that exist within an ecosystem Appreciate how understanding how living systems work is vital to human survival.

The environment The environment is every living and non-living thing that surrounds an organism. Biotic factors refer to the living parts of the environment. Other members of the same species, predators, prey, etc. Abiotic factors refer to the non-living parts of the environment. Oxygen, sunlight, temperature, etc. Any portion of the environment is referred to as an ecosystem.

Ecosystems Ecosystems, or ecological systems, can be very large or very small. The forest canopy, an underground cave, or even a seasonal pond are all examples of ecosystems. The specific environment in which an organism lives is called it’s habitat. Forests, lakes and deserts are all examples of habitats.

Populations All of the members of a single species that live in the same area make up a population. All the earthworms that live in the wooded lot next to our school would be a population.

Communities A community refers to all of the different populations that live in a specific area. In our wooded lot, the community would include earthworms, but also all the ants, squirrels, birds, trees, fungi etc. that also live there.

The biosphere All of the inhabited areas on earth, be they underground, at the tops of mountains, or on the ocean floor make up the biosphere. If there is life present in any earthly location, it is considered part of the biosphere.

Biomes Biomes are large geographic regions in many locations with similar kinds of communities and climates. Climate is a very important component to a biome because many species of plants and animals can only tolerate small changes in abiotic factors such as temperature and humidity.. There are 8 biomes on earth.

The great “8” There are 2 water biomes: Freshwater and saltwater. There are 6 land biomes: tundra, taiga, temperate deciduous forest, tropical rain forest, grassland, and desert.

Tundra Taiga temperate deciduous forest Tropical Rain forest Grasslands Deserts

Environmental Limits on population size The resources available in an ecosystem are not unlimited. Because of this, populations do not increase to an unlimited size. The number of organisms in any single species that an ecosystem can support is called it’s carrying capacity. Carrying capacity is determined by several biotic and abiotic factors.

Biotic factors Examples of some biotic factors which limit population size are: Competition: Members of the same species struggling to obtain resources, such as food and mates. Predators: Organisms which kill and eat other organisms. Prey: Organisms which serve as food for other organisms. Pathogens: Disease.

Abiotic Factors Examples of abiotic factors which limit population size are: Temperature: Many organisms cannot tolerate even small changes in temperature. Sunlight: Some species of plants will die is they receive too much or too little sun. Water: pH: In the soil or water will determine which species can survive there.