Paper 1 - Section B, Ecosytems Flashcards
What are producers
Producers convert energy from the environment into sugars. For example, plants that convert energy from the sun by photosynthesis
What are consumers
Consumers get energy from (eg a pond snail gets its energy from eating plants)
What are decomposers
Decomposers break down plant and animal material and return nutrients to the soil eg bacteria and fungi
What is a food chain
A food chain shows direct links between producers and consumers in a simple line
What is a food web
A food web shows all the connections between producers and consumers in a rather complex way
What are some examples of abiotic factors in a freshwater pond ecosystem
- solar radiation
- temperature
- depth of water
What are some examples decomposers in a freshwater pond ecosystems
Bacteria and fungi
What are some examples of consumers in a freshwater pond ecosystem
- frog
- duck
- pond snail
What are some examples of producers in a freshwater pond ecosystem
Grass, algae and bushes
What would happen if the pond became polluted
Plants and animals would die and this could cause a knock-on effect up the food chain and effect the whole thing
What would happen if an animal in a food chain went extinct
Its prey would no longer be hunted and its predator would no longer have any food and can cause a chain of reactions effecting the ecosystem. For example, the prey would overpopulate as there would be nothing hunting it
What are the 5 habitats within a freshwater pond ecosystem
- Above the surface
- The surface
- Pond margin
- Midwater
- Pond bottom
Describe the surface within a freshwater pond ecosystem
- plenty of oxygen
- animals breathe through gills, skin or lungs
Describe above the surface in a freshwater pond ecosystem
- birds and animals breathe oxygen
- food found in or in water or in the margins
Describe the pond margin in a freshwater pond ecosystem
- plenty of oxygen, light and shelter for plants and insects for small animals to eat
Describe midwater in a freshwater pond ecosystem
- animals breathe through gills/skin
- fish are the main predators
- food found on the surface or in pond
Describe the pond-bottom in a freshwater pond ecosystem
- little oxygen or light
- plenty of shelter and food
- decomposers and scavengers live here
What is an example of a food chain in a freshwater pond ecosystem
Solar energy —> algae (producer) —> mayfly (consumer) —> fish (consumer)—> heron (consumer) —> pond snail (decomposer)
What does it mean if an ecosystem is said to be in equilibrium
All the components of an ecosystem are in balance
What are natural causes of change in an ecosystem
- extreme weather events (eg flooding)
- volcanic eruptions
- climate change
What are human causes of change in an ecosystem
- ponds may be drained for farming
- woods cut down
- urbanisation
How does climate control the distribution of tropical rainforest ecosystems
- sunlight, temp and rainfall can affect the type and number of plants that can grow
- TRF contain greatest variety and density of plant growth because they are located in climate zones where temperatures are warm and wet
- warm due to being near the equator, and wet because low pressure zone created by rising warm air at the equator
