Introduction to Ecosystems

Big Ideas Stewardship – taking responsibility for the management and care for the planet Environment – all the living and non-living things that exist on earth and their interactions with each other Sustainability – using the planet’s resources in a way that will allow living things to live, interact and reproduce indefinitely Biodiversity – the number of types of organisms (living things) in an area. The more types of organisms there are in an area, the more biodiversity the area has. Ecology – the study of how organisms interact with each other and with their environment

Systems A system is a group of individual parts (components) that interact to accomplish a task For example, a bike has many components that interact to allow a rider to move

Ecosystems and their Components An ecosystem is complex – it has many components An ecosystem is self-regulating – if one part of it is damaged or disappears, it impacts everything else An ecosystem has biotic and abiotic factors

Biotic and Abiotic Factors Biotic factors: organisms such as animals, plants, fungi, bacteria, and algae Abiotic factors: everything else! Physical things: Rocks, air, water Things that can be measured: Air temperature, hours of daylight, salt concentration in seawater

Biotic or Abiotic? Wild Mushrooms BIOTIC

Biotic or Abiotic? Temperature and Precipitation ABIOTIC

Communities Within Ecosystems Species – a group of similar organisms in an ecosystem They can reproduce with each other, and their offspring can reproduce Example: grey squirrels are very common in Ontario They can reproduce with one another, but can NOT reproduce with red squirrels, which also live in Ontario

Communities Within Ecosystems Population – a group of members of the same species that live in the same area Habitat – the physical environment in which an organism lives Example: All grey squirrels are a part of the same species, but they are not all a part of the same population One group’s habitat might be a pine forest, while another’s might be a park These two groups are in two different populations

Communities Within Ecosystems A community is made of populations of different species that live and interact in an area Example: a park is a community that contains populations of squirrels, robins, trees and shrubs They all interact with each other and with abiotic factors in the environment to make up the ecosystem

Communities Within Ecosystems Niche – all of the interactions of a species with its ecosystem Example: the niche of grey squirrels includes: eating nuts and other seeds being hunted by foxes an owls being active during the day living and nesting in trees It’s a species specific role within its ecosystem

Size of Ecosystems Ecosystems vary widely in size Can be as tiny as a drop of water or as large as a desert or an entire ocean! A drop of water can contain: Biotic factors: millions of tiny organisms like bacteria and algae that interact with each other Abiotic factors: nutrients and sunlight that help the organisms grow and reproduce

Biomes Ecosystems combine to make biomes A biome is a large area that contains similar ecosystems All of these ecosystems are interconnected There are terrestrial biomes (land biomes) and aquatic biomes (water-based biomes) Aquatic biomes can be divided into Marine biomes (high salt content) Freshwater biomes (low salt content)

Terrestrial Biome Deciduous Forest – Southern Ontario is mostly this kind of biome

Marine Biome Coral Reef

Biosphere Biomes combine to make the biosphere Biosphere = the part of the planet (water, land, air) where life exists It is very thin relative to the earth If we think of the earth as a beach ball, the biosphere could be represented by a single sheet of plastic wrap on its surface

Three Main Parts Three interacting parts make up the biosphere: The atmosphere: the layer of gases that surrounds Earth The lithosphere: the solid outer layer of the Earth, which includes the soil The hydrosphere: all water on Earth; only 3% of this is fresh water