Nature of Ecosystems Flashcards
What is an ecosystem
A living system of plants and animals which interacts with the physical environment.can be considered at any scale. Includes all the biotic and abiotic Factors
What is a biome
An ecosystem on a global scale with a climax community of plants and animals which has reached equilibrium with its environment. Has distinctive climate and vegetation
Define biotic
The living environment
Eg vegetation,mammals, insects , birds
Define abiotic
The non living, chemical and physical components includes climate
Eg soil characteristics, relief of land , drainage characteristics
Energy in an ecosystem
Enters by photosynthesis this is stored in plants and passed up food chain when plant is eaten. Energy passed on when one organism eats another.
What is biosphere
The living world includes oceans and lakes, anywhere that’s able to support and maintain life.
What’s included in an EcoSYSTEM
Inputs
Outputs
Flows and stores
Inputs of an ecosystem
Energy from the sun drives photosynthesis so plants grow
Others include animals and water from precipitation or rivers
Outputs of an ecosystem
Energy or nutrients leaving an system eg animals move p, water move out in rivers, evapotranspiration, through flow,groundwater flow
Flows of an ecosystem
Nutrients being transferred from one store to another eg from soil to vegetation
Stores of an ecosystem
Main places nutrients are held
- in vegetation
- plant litter
- soils
Tropic levels
Each stage in a food chain/web and the amount of energy in stages of an ecosystem
Describe producers(autotrophs) role in food chains
Occupy first tropic level and make own food eg plants
Describe primary consumers role in a food chain
In the second tropic level and eat producers can be omnivores or herbivores
Secondary consumers role in a food chain
Occupy the next level (3rd?) and eat consumers mainly feeding on herbivores
Tertiary consumer (top predator) role in food chains
Next trip level ( highest ones) they eat secondary consumers , can be omnivores
What’s an omnivore
Animals that eat plants and animals
Define biomass
The total of plant and animal life in an ecosystem
How does biomass vary at each tropic level
Decreases with each tropic level
What’s a herbivore
Eats plants
What’s a carnivore
Eats meat
How is energy lost in an ecosystem through tropic levels
Through life processes dog respiration, movement and excretion- around 90% of energy contained in each level lost
10% available for next level as food. So number of organism in an ecosystem decreases as tropic level increases
Ways energy is lost at each level in food chain
Lost between sun and autotroph - not all used in photosynthesis -some on areas that don’t photosynthesise
Some parts of organism not eaten
Some lost as waste
Movements and body heat
What’s a decomposer
Organisms that breaks down dead plants, animals ,and waste matter eg fungi and bacteria
What’s a Detritivore
Animal that feeds on dead material or waste product
What are nutrients
The chemical elements and compounds needed for organisms to grow and function
What is soil
A mixture of weathered rock,air, water and decomposed organic matter on the surface of the earth
What is litter
The amount of dead organic matter ontop of the soil
In gersmehl diagrams what does the size of the compartments and arrows show
The amount of nutrients stored in each compartment or flowing between compartments
The nitrogen cycle
Necessary for construction of plant and animal matter. Present in atmosphere and can be fixed in soil by some plants. Taken up by roots passes through ecosystem and returned to soil by decomposition
The carbon cycle
Carbon dioxide is in atmosphere. Stored in ground as peat,coal,oil and gas. Also in stores in plants, animals and soil. Burning of fossil fuels and destruction of forest releases it back into atmosphere. It’s used photosynthesis to produce carbohydrates. Plants eaten by animals, released by respiration. Carbon dioxide in decaying matter and waste
