topic 9: ecosystems and environments Flashcards
how can humans affect ecosystems
poaching, farming, consuming, keeping as pets
what is food security
having access to enough healthy food at all times.
what is eutrophication
adding more nutrients to an ecosystem that normal
what things would they lack? Think money
what problems would poorer countries have with food security
not having enough money so not being able to buy good-quality seed, fertilisers, farm equipment, that all increase crop production
why could increasing human population affect food security
more people will need more food, there will be less good land for growing food as the available land will be dedicated towards housing
what are some advantages of fish farming
mass production of fish, reduces over fishing
what is the definition of sustainability
ability to continue something such as food production at the same level without negative effects now or in the future
what is the definition of native/indigenous
organisms that have always been in a area/country
what is the definition of non-indigenous
organisms that have been introduced into an area
what are the steps of the water cycle
1) Water evaporates from oceans, lakes and rivers to form water vapour.
2) As air rises it cools, so water vapour in it condenses to form clouds.
3) As water droplets get too large and heavy, they fall as rain or snow.
4) Rivers flow into lakes and eventually the water returns to the ocean.
what is desaliination
process used to produce potable water from salt water by extracting mineral salts (distillation in chemistry
define sedimentation
deposition of solid materials at the bottom of water
define combustion
burning of organic compounds
define photosynthesis
the process in which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.
define decomposition
process of decay
define fossilisation
preservation of organic matter
define weathering
break-down/erosion of rocks and sediments
what is the word and chemical equation for respiration
glucose + oxygen = carbon dioxide + water (and energy)
C6H12O6 + 6O2 → 6CO2 + 6H2O
how would deforestation affect the carbon cycle
-the carbon dioxide stored in the tress will be released into the atmosphere increasing the amount of Co2 in the air
-less trees will mean that the excess co2 in the atmosphere will not be turned into oxygen though photosynthesis
why is carbon so important
-found in all living things
-found in air, land and water
what role do decomposers play in the ecosystem
they break apart dead organisms into simpler materials making the nutrients available to primary consumers
define an ecosystem
all the organisms and the environment in which they live
population
groups of the same species within the ecosystem
habitat
the particular area in which different populations live
Describe how you might use a 1m x 1m quadrat to estimate the number of dandelions in a 100m x 100m field.
.Place multiple tape measures along the length and width of the field, forming a large grid.
.generate 10 random pairs of coordinates
.Calculate the mean number of dandelions per m2.
.estimate the the total population by timesing the average with the total surface area
what does abundance refer to
the amount of the population
what does distribution refer to
where the individuals of the population are
how do scientists use sampling
‘sampling’, where they only measure a subset of the organisms, and use that subset to make predictions about the whole population.
what is a transect
A line through a habitat along which organisms are sampled
why is it important to have good biodiversity
.It increases the stability of the ecosystem, so that changes are less likely to have adverse affects
.Many species provide specific services, such as pollination
.Many of our medicinal drugs come from wild species
what is eutrophication
it’s caused by excess nutrients that have leached into waterways.
explain the process of eutrophication through leaching
.fertilisers ‘leach’ into bodies of water (often ponds or still bodies of water)
.the excess nutrients stimulate rapid growth of algae on the surface of the water.
.the algae block sunlight from reaching the plants underneath.
.this prevents the plants from photosynthesising and they begin to die
.decomposers feed on the dead plants and deplete the water from oxygen when they do so
. the animals (fish and stuff) die from lack of oxygen
how can the government encourage businesses (including farmers) to reduce damage to biodiversity.
. paying practices for carrying out certain beneficial methods
.setting yearly limits on harmful practices
How do field margins and hedgerows in agriculture help increase biodiversity?
they provide extra habitats and food sources so that a wider range of species can survive.
Why could the rate of decomposition fall if soil becomes waterlogged?
the oxygen levels will fall, which will decrease the rate of decomposition so there will be less aerobic respiration
what are ways to preserve food
.low temperature to slow the rate of decomposition
.air tight containers to prevent microorganisms from contaminating the food
.removing water so microorganisms can’t survive or reproduce
.using gamma radiation to destroy any microorganisms
what are some abiotic factors
.temperature
.light
.water
.pollutants
what are the biotic factors
competition and predication
what are some disadvantages of fish farming
.parasites and disease spread easily as the fish are in close proximity
.
how is energy lost between trophic levels
respiration
waste
movement
what are biotic factors
organisms in an ecosystem that effect other 7living organisms
what is the name of the indicator lichen
Lecanora conizaeoides
what are the two air pollution indicator species
blackspot fungus
indicator species for clean water
-stonefly nymph
-dragonfly nymph
-freshwater shrimp
indicator species for polluted water
-water louse
-bloodworms
-sludge worms
no life
what is parasitism
feeding relationship in which a parasite benefits by feeding off a hist organism causing harm to the host
what are 3 examples of mutualistic relationships
-flowers and pollinating insects
-clown fish and sea anemone
-cleaner fish and larger fish
how do clown fish and anemones have a mutualistic relationship
the sea anemone has stinging tentacles that hide the clown fish from predators
clown fish chase of the anemone’s predators and provide nutrients in their faeces
