Topic 9- Ecosystems and material cycles Flashcards
what is abiotic
non living
sunlight, temperature, gas and water etc
what is biotic
living things in an ecosystem
plants, animals, bacteria etc
How can communities be affected by abiotic factors such as temperature, light, water and pollutants
wind speed- effects rate of transpiration, cooling effect and no trees found there
light- changes temperature, rate of photosynthesis and rate of respiration
soil-nutrients, ph acidity and temperature controls what can and cannot grow there
wind temp- different types of wind bring different weather types
humidity- crops wouldn’t grow without it
How can communities be affected by biotic factors such as competition and predation
predating- reduces the number of prey which effects population of that species - keeps everything in balance as if they didnt exist then a single species could become dominant over others
competitors-species that are well adapted may get fewer of the resources it needs, less likely survive and could result in extinction. However competition could lead to more specialisation as species evolve with better characteristics
describe the importance of interdependence in a community
interdependence between plants and animals is what forms food chains and webs, each section producer, primary, secondary, and tertiary depend on each other for food/energy
describe how the survival of some organisms is dependent on other species, including parasitism and mutualism
primary consumers rely on plants to grow, secondary consumers rely on plants to grow so primary producers survive etc
describe practical investigating the relationship between organisms and their environment
x
How can energy in trophic levels be effected
some energy is transferred to less useful forms at each tropic level, and this affects the number of organisms at each trophic level, limiting the length of food chain and determining the shape of a pyramid of biomass in an ecosystem
what do we call a plant that uses photosynthesis
autotrophs
what is the biggest type of competition
intra-specific- members of the same species compete for limited resources
direct combat over a resource eg- mate or food- need same resources because they are the same species which increases competition
Mechanisms to diffuse confrontation- size, colouration, ornamentation used to signal status of owner or position in hierarchy
Major overlap in resource use between same species so major force in ecology
what is inTErspecific
a form of competition whereby organisms from different species compete for the same resources in an ecosystem eg- food or living space
what does the size of a predator population depend on
depends on size of prey population and vice versa
what is density dependence
the relationship between fitness and population size
what does an increased density mean
increase in intraspecific competition
what do food chains show
shows where the energy goes in a food chain (what eats what)
what is a photoautotroph
uses sunlight to produce energy
what is a chemoautotroph
does not use sunlight, has other ways of producing energy eg- bacteria using chemical energy to produce carbohydrates
what do consumers do
eat other autotrophs or consumers
what are the different levels of a food chain and how do we show them
producer - plant
primary consumer-1- herbivores
secondary consumer-2- omnivores
tertiary-3- herbivores
what are hetrotrophs
herbivore
carnivore
omnivore
between each level how much energy is transferred
only 10% of energy gets transferred
100, 10, 1, 0.1
what happens as we go up the food chain
energy is lost as we go up the food chain, population gets smaller as we go up the food chain
what does a pyramid of numbers show us
what does pyramid of biomass show us
how many animals or organisms we are talking about- can have odd shapes
biomass shows their mass-always look like pyramids
how can we make a food chain more efficient
reducing number of stages
reduce an animals movement or keep it warm
use plant hormones to regulate ripening of fruit
how to calculate the efficiency of energy transfer between trophic levels
energy transferred to next level / total energy in x 100
how to calculate changes in biomass
increase in biomass-decrease in biomass= net change in overall biomass
what is the definition of a parasite
take resources but do not contribute anything good towards organism
what is a parasite
an organism that grows, feeds and lives on or in another organism to whose survival contributes nothing
give example of a parasite
pthirus pubis
what are the disadvantages of being a parasite
parasites are dependent entirely on their host and specific to that host eg- fleas when a flea bites you- your blood kills a flea as its not an animals blood
what does it mean to be symbiant
an organism that is associated with another in a mutually beneficial relationship. We call this relationship mutualism
give example of a mutualism relationship
nitrogen fixing bacteria and plants
plants provide bacteria with glucose and bacteria provides plants with nitrates
what are the positive and negative effects of human interaction of ecosystems and their impacts on biodiversity - FISH FARMING
fish farming-
+=controlled water quality, frequent feeding allows rapid growth and protection against predators
-= greater risk of disease as fish may be closely related due to selective breeding
large amounts of waste produced by the fish causes eutrophication
what are the positive and negative effects of human interaction of ecosystems and their impacts on biodiversity- INTRODUCTION OF A NON INDIGENOUS SPECIES
foreign species is introduced on purpose or by accident by humans, the species becomes non indigenous, introduced
Some of these introduced species can become established are now called naturalised species
Some naturalised species can spread quickly and out compete native a species- now called invasive species
why are fish kept in separate tanks
intraspecific competition- reduced by keeping fish of different ages in different tanks
interspecific- reduced by keeping different species in different fish tanks
what is eutrophication
1-nitrates from fertilizers leach through ground or enter rivers by rainfall
2-plants flourish- these pollutants cause aquatic plant growth of algae- the algae blooms and oxygen is depleted, and go to surface of water, blocking out sunlight for other organisms- cannot do photosynthesis- animals lose food source and die.
3- dead matter is decomposed by decomposes which releases CO2, algae uses all nutrients and they die, go to bottom of lake and also get decomposed and all oxygen is gone.
4- oxygen levels are so low nothing can live there- anoxic
List the biological factors affecting levels of food security
- increasing human population
- increasing animal farming and increase meat and fish consumption
- impact of new pests and pathogens
- environmental change caused by human activity
- Sustainability issues eg- use of land for biofuel production and cost of agricultural inputs
how to calculate rate changes in the decay of biological batter
Change in value / change in time
difference between ecosystem and habitat
an ecosystem= an area in which all the living organisms and all the non living physical factors form a stable relationship that needs no input from outside the area to remain stable
a habitat- the place where an organism lives eg- woodland, seashore
difference between community and population
community- all the different organisms living and interacting with one another in a particular area
population- a group of one species living in the same area
what is the water cycle
Energy from the suns heat causes water to evaporate.The warm air rises carrying water vapour with it
Transpiration form plants releases water vapour into the air
The moist air cools down as it rises, it condenses back into a liquid, this condensation process produces clouds
As the water droplets in the clouds get bigger and heavier , precipitation occurs
what is the carbon cycle
Carbon enters the atmosphere as co2 from respiration and combustion
Carbon dioxide is absorbed by producers to make carbohydrates in photosynthesis
Animals feed on the plant passing the carbon compounds along the food chain, they die
The dead organisms are eaten by decomposes and the carbon in their bodies is returned to the atmosphere as co2.
whats the importance of the carbon cycle
processes involved and role of microorganisms as decomposes
without decomposes carbon would get trapped/locked which forms fossil fuels
whats the importance of the water cycle
process involved and production of potable water in areas of drought including desalination- removing salts and minerals from water
how are nitrates made available for plant uptake
use of fertilizers, crop rotation and role of bacteria in the nitrogen cycle
explain the effects of temperature, water content and oxygen availability on rate of decomposition in composting
x
evaluate the uses of indicator species as evidence to assess the level of pollution
polluted water- bloodworm, sludgeworm
clean water- fresh water shrimps an stone fly
air quality- different species of lichen, black spot fungus on roses
Explain the effects of temperature, water content and oxygen
availability on the rate of decomposition in food preservation
x
what is the carbon cycle in the sea
marine animals may convert some of the carbon in their diet to calcium carbonate which is used to make shells. Over time shells of the dead organisms collect on the sea bed and form limestone. Due to the earths movements this limestone may eventually become exposed to the air where it’s weathered and the carbon is released back into the atmosphere as carbon dioxide
what is the nitrogen cycle
78% of the air is nitrogen gas, nitrogen is too unreactive to be used directly by plants to make protein. It must be converted into soluble ions, such as nitrates. Nitrogen fixing bacteria in legumes do this
When animals eat a plant, nitrogen from that plants proteins becomes proteins in the animals.
Decomposers break down Urea, egested material (faeces) and dead bodies. The nitrogen returns to the soil as ammonium ions which bacteria can convert into nitrates for plants to absorb
Denitryifying bacteria in soil break down nitrates and return nitrogen to the air,
