Resilient PlanetMission 1

Invaders: A Constant Ecological Battle

Life on Our Planet• Life exists on Earth in only a thin

layer on its surface• Earth’s biosphere is the thin

layer on our planet’s surface that contains life

• The biosphere exists over the whole planet, both on land and in the sea

• The biosphere is divided into smaller units called ecosystems.

Ecology• Ecology – the

study of the interactions of life among living things and their environment.

Ecosystems• An ecosystem is a community of

interdependent organisms and their communities.

• Ecosystems can be as large as hundreds of square miles, like the Sahara Desert

• Ecosystems can be as small as a pool of water

Parts of an Ecosystem

• Abiotic factors – nonliving parts like rocks, moisture, the amount of sunlight and temperature

Parts of an Ecosystem• Biotic factors – parts that are living or where

once alive, such as plants, animals, bacterium, and the remains of what was once alive, like rotting trees and deceased animal matter.

Parts of an Ecosystem• Abiotic factors support the biotic factors,

sustaining the life in the ecosystem.

Classifications within Ecosystems

• Biotic Classifications– Organisms – any individual life form, ranging from

plant to animal to bacterium

Classifications within Ecosystems

• Species – a class of organisms that share common characteristics and specific hereditary traits

Classifications within Ecosystems

• Population – the number of a particular species in a specific geographical area

Classifications within Ecosystems• Community – different populations of

organisms that interact with each other.

• Biodiversity– the number and variety of organisms that live in an ecosystem.

Classifications within Ecosystems

• Predator – an animal that captures and eats other animals

• Prey – an organism that is captured and eaten by another a predator

Habitats in an Ecosystem• Habitat – a place where an organism can find

what it needs to survive, in terms of both biotic and abiotic factors.

Habitats in an Ecosystem• Niche – the combination of behaviors and

resources that an organism is adapted to exploit.

• Competition – when two or more organisms rival for resources.

Habitats in an Ecosystem

• Carrying capacity – the largest population that an environment can support over a long period of time

• Limiting factors – the biotic or abiotic factors that restricts the growth of a population.– Limited food– Limited space– Other examples?????

Biomes• Biomes are a way to describe a large group of similar

ecosystems.• Land biomes are grouped by precipitation ranges,

temperature ranges, geography and the plants that grow in that area, for example:

Biomes

Biomes• Similar biomes are found throughout the

world, each containing many unique ecosystems.