B9 ECOLOGY Flashcards
Ecosystem
An area in which the interactions between all the living organisms and all the physical factors form a stable relationship needing no external input
Habitat
A Particula area within an ecosystem
Community
All the organisms living in an ecosystem
Interdependence
The way in which the organisms in an area depend on each other for food shelter protection and so on
Population
The members of one particular species within an ecosystem
Abundance
The number of members of one species in an ecosystem
Quadrat
I metal square used to help find the number of small organisms living in an area
Random sampling
Estimating the population of organisms in an area by randomly dropping a contract several times finding the average number of organisms present and scaling up your answer
Population size
Population size equals number of organisms in quadrat times total area divided by contract area
Abiotic factor
A non-living factor that influences what can live where
Important abiotic factors
Temperature light intensity rainfall type of landscape soil pH soil nutrients pollution
Pollutants
Substances produced by human activities that can poison some or all of the living organisms in an area
Adaptations to abiotic factors
Features of plants and animals that are suited to the abiotic factors where they live
Changes to abiotic factors
If abiotic factor changes such as temperature increases due to global warming organisms may no longer be well adapt to where they live and may die out
Biotic factor
Anything factor that influences what can live where
Important biotic factors
The presence of food organisms predators competing organisms and disease
Competition
Often two or more different organisms may compete for the same resources such as food water or light
Effects of reducing competition
Reduced competition when a species go extinct can lead to unpredictable events on another species with some benefiting from reduced predication and others benefiting
Predator prey cycle
Asked a number of prey animals increases the number of predators increase the predators over predate the prey leading to a fall in prime numbers which causes the number of predators to go down as there is less food the number of prey increases again because you are being eaten
Parasitism
A speeding up relationship in which a parasite phase of its host causing harm to the host but normally not killing it
Examples of parasites
Please and lead to sucking blood tapeworms living in animals mistletoe burrowing it’s roots into tree branches
Mutalism
Organisms that live together in a relationship where both benefit
Example of mutalism
Cleaner fish that swim into sharks mouth started without being eating algae that live inside coral polyps gaining shelter and providing food
biodiversity
The number of different species living in an area
High biodiversity is good
Fish farms
Farms based in water where fish are farmed in pens to reduce the need to catch them in the wild
Effect of fish farming on biodiversity
The waste produced by the fish sinks to the sea floor changing the conditions and harming the organisms living there
Introduced species
Organisms introduced by humans intentionally or accidentally into a new ecosystem
Effect of introduced species on biodiversity
Many introduced species upset natural ecosystems by changing the food web introduced species often lack of predators that can control their numbers
Eutrophication
Fertiliser used on farmland gets washed into lakes and rivers by rain it causes algae to grow out of control and when the algae dies it sinks to the bottom of rots which uses of the oxygen in the water
Effects of eutrophication on biodiversity
With less oxygen in the water many species die and biodiversity is reduced
Importance of biodiversity
Areas with high biodiversity recover more quickly from disasters such as floods and droughts many plants and animals are useful for new medicines and products
Endangered
When a species is at risk of dying out usually because it has been over hunted or its habitat has been destroyed
Conservation
When an effort is made to protect rare or endangered species or their habitat
Importance of conservation
Conservation Can make the difference between a species dying out or surviving it increases biodiversity
Reforestation
Planting trees or allowing trees to grow and on old farmland it increases biodiversity by increasing the range of habitats in an area
Captive breeding programs
Breeding animals in zoos where they are protected from danger in order to be able to release them into the wild
Water cycle
The way in water is continuously moved around different plants of the environment
Water cycle stages
Precipitation Surface run off Infiltration Evaporation Condensation
Precipitation
Water falls to the ground as rain snow and hail
Surface run off and infiltration
Water soaks into the ground or banned off into streams and rivers into lakes and oceans
Evaporation
Water evaporates as water vapour from oceans lakes and rivers
Condensation
Water vapour condenses into tiny droplets to form clouds
Desalination
Producing portable drinking water from salty water for example by distillation useful in areas of low rainfall
Carbon cycle
The way carbon is continuously moved between different stores in the environment
Carbon cycle photosynthesis
Carbon is transferred from the carbon dioxide in the air into plants
Carbon cycle feeding
Carbon is transferred from plants into animals and from animals into our animals
Carbon cycle death and excretion
Carbon is waste and dead bodies is transferred to decomposes or to fossil fuels
Carbon cycle respiration
Plants animals and decomposes transfer carbon back to the air as carbon dioxide by respiration
Carbon cycle combustion
Humans transfer carbon back to the air by burning fossil fuels
Importance of nitrogen
Nitrogen is used to make amino acid’s which are used to make the proteins needed for growth and repair
Nitrogen cycle
The way nitrogen is continuously moved between different stores in the environment
Nitrogen cycle
Nitrogen fixation
Nitrogen in the air is converted to nitrates in the soil by nitrogen fixing bacteria
Nitrogen cycle
Plants
Plants absorb nitrates from the soil and covert then into amino acids and proteins
Nitrogen cycle
Feeding
Animals eat plants transferring nitrogen into them in the from of protein.
Nitrogen cycle
Death and excretion
Nitrogen in the form of urea and protein is transferred to decomposers in the soil by death and excretion
Nitrogen cycle
Decomposers
Decomposers concert nitrogen in urea and proteins into nitrates
Nitrogen cycle
Denitrification
Denitrying bacteria in the soil convert nitrates back into nitrogen gas in the air
