ecology Flashcards
what do animals fight for in an ecosystem
space
food
water
mates
what does abiotic factor mean
non living factors of the environment
what do plants fight for in an ecosystem
light
space
water
nutrients
three examples of abiotic factors
light intensity
temperature
moisture level
how can changes in abiotic factors affect poulations
decrease in light intensity —> decrease the rate of photosynthesis —> affect plant growth —> decrease in population
what does biotic factors mean
living factors of the environment
three biotic factors
New predators
Competition
New pathogens
Example of a knock on effect from biotic factors
two squirrel species competing for the same food. one Outcompete the other meaning the other population decreases.
what are the three ways of adaption?
Structural, behavioural, functional
what is structural adaptation
features of an organisms body structure, e.g shape or colour
what is behavioural adaption
ways the organism behaves e.g seasonal migration
What is functional adaption?
things that go on inside organisms body, e.g hibernation lowers metabolism, dont have to hunt when food is scarce
what is biomass
material from plants and animals
what happens to some of glucose in a plant
made into other biological molecules (biomass), aka the plants energy store
order of food chain
Producer
Primary consumer
Secondary consumer
Tertiary consumer
what pattern are predatory-prey cycles
out of sync - takes a while for each population to respond to a changr
what does a quadrat measure
abundance of species in an area
what does a transect measure
how distribution changes across an area
how can you ensure quadrats are placed randomly
throw them
close your eyes and place them somewhere
how can you use a quadrat to measure abundance in a certain area
• place the quadrat randomly
• count the organisms within the quadrat
• repeat as many times as possible
• work out mean
• multiply the mean by the total area of the habitat
how can you use a transect to record distribution
• mark out a line using tape measure
• use quadrat to count organisms/percentage cover at 0m
• record in table
• repeat at regular intervals across line
• plot onto graph
how do you calculate percentage cover
• count the number of smaller squares in the quadrant that are covered by the organism you are studying
• squares covered/total squares x 100
three changes that affect distribution of an organism
Temperature
Availability of water
Composition of atmospheric gases
what are the four steps of the water cycle/recycle?
• evaporation/transpiration (from plant)
• condensation
• Precipitation
• drains into see
How are elements cycled back to the start of the food chain? 5 steps
• living things made of material they take from their environment
• These get passed down the food chain
• these materials are returned through waste products or decay
• decay Happens faster in warm, moist, aerobic conditions (microorganisms are more active)
• decay put this stuff that living things need to grow back into the environment
How should recycling elements in the food chain work in a stable community?
Materials taken out of environment = materials put back in
General example of cycle of elements in food chain
• plants turn elements e.g oxygen, carbon, nitrogen into the complex compounds (carb, prot, fat)
• these get passed up food chain
• organisms in food chain die
• Decay stuff that plants need to grow e.g mineral ions back into soil
Order of carbon cycle
6 steps
• plant and algae photosynthesise, CO2 removed from atmosphere for glucose
• this CO2 is passed into consumers
• CO2 returned when animals respire
• decomposition of animals and plants releases CO2
• these dead organisms are also use as fossil field
• Combustion of these releases CO2
what is compost?
Decomposed organic matter
Used as natural fertiliser
What do you call the animals and microorganisms that feed on dead remains?
Detritus feeders
Four factors that affect the rate of decay
temperature
Water availability ab
Oxygen availability
Number of decay organisms
What conditions create a fast rate of decay?
warm temperature
Moist environment
Available oxygen
Numerous microorganisms and detritus feeders
what is biogas?
Anaerobic decay waste material
what is an extremophile
microorganisms adapted to live in very extreme conditions
How can anaerobic decay produce fuel?
By decaying plant and animal waste anaerobically, microorganisms can produce biogas. Biogas is mainly made up from me thing which can be burned as fuel.
Bio gas cannot be stored at a liquid must be used straight away
Batch generator versus continuous generator
Batch: small batches manually loaded with waste
Continuous: produced all the time, waste continuously fed in at steady rate, large scale
what must a biogas generator have?
Inlet for waste material
Outlet for digested material
Outlet for biogas to be piped
What is biodiversity?
The variety of different species of organisms on earth or within an ecosystem
Why is biodiversity so important?
Keeps ecosystem stable: species depend on each other for shelter and food
What are some things that increasing population population leads to?
• demand for space – deforestation
• demand for agriculture - land space, rice crops, eutrophication
• demand for nonrenewable resources, e.g. oil to make luxuries
Increased pollution in water land and air
how does global warming work/greenhouse effect?
Increased greenhouse gases pollute the atmosphere. This absorbs more energy from the Sun and traps it
Four consequences of global warming
levels rising
Changes in species distribution
Changes in migration patterns
Reduction and biodiversity
what is a peat bog
Plants that live in bogs don’t fully decay as there is not enough oxygen. These partly rotted plants build up to form Peat. Carbon is stored in the peat
How to peat bogs contribute to warming
The books are often drained to create space for farmland or peat is cut unused for fuel.
This exposes it to more oxygen, resulting in decomposition
three consequences of deforestation
Less carbon dioxide taken in
More carbon dioxide released
Less bio diversity
four programs to protect ecosystems and biodiversity
breeding pro
Habitat protection
Reducing deforestation
Reducing waste
four conflicts in protecting ecosystems and biodiversity
Cost
Economy E.G employment
Food security e.g pesticide laws
Development of society (demand)
Dietary categories of each trophic level
One: producer
Two: herbivore
Three: carnivore
Four: carnivore
3 deomposers
bacteria
Fungi
Detritus feeders
how does decomposition work
Decomposers secrete enzymes that break the dead stuff down into small soluble food molecules
These then diffuse into the microorganisms
what do the different layers show on a pyramid of biomass?
Relative mass of living material
- How much all the organisms would weigh
why does biomass get lost
organisms don’t eat every part
Organisms don’t absorb everything, rest is released as faeces
Some biomass is converted into other substances
formula for efficiency of biomass transfer
biomass transferred to next level/biomass available from previous level
x100
What factors can affect fArming?
Lupus, pathogens, environmental conditions
Two ways to maintain fish stocks
fishing quotas – limits number and size of fish that can be caught
net Size - reduce number of unwanted fish being killed. younger fish can escape and breed.
advantages of factory farm
Limits the movement which reduces energy transfer
Energy not wasted maintaining temperature
more energy csn be used for growth, more food produced
two disadvantages of factory farming
Disease spread easily
Ethical objections
