B18 - Biodiversity and ecosystems Flashcards
What is biodiversity
a measure of the variety of all the different species of organism in an ecosystem
What is the benefit of having biodiversity
it reduces the dependence of one species on another for food, shelter and maintenance of the physical environment
What is the effect of the loss of a species of ecosystems with high and low biodiversity
- high : little effect
- low : large effect
why has the human population been able to grow so fast
- lack of predators
- grow lots of food
- cures for disease
how is land consumed by humans
- industrial areas
- farms
- quarries
- processing waste
what are some problems with how we manage waste
- water gets polluted with sewage
- air we breathe contains pollutants
- land is polluted with chemicals
- these can wash into water
how do people pollute land
- waste disposal
- toxic chemicals
- side effect of farming e.g. herbicides etc.
how do people pollute water
- sewage water washed into sea
- toxic chemicals drain into rivers and seas
- ## lots of ions from fertilisers cause growth stimulation in plants, which causes others to die out, which causes lots of decomposers
why are green ponds bad
because all the animal life it once had is dead due to lots of competition for resources
how is acid rain produced
sulfur in fuels reacts with oxygen in air to make sulfur dioxide, which causes acid rain
- nitrous oxides are produced in car engines
What is the effect of acid rain
- why is it dangerous to places far from where it was created
kills animals and plants, corrodes buildings
- wind
how have some countries reduced likelihood of acid rain
- using low sulfur alternatives e.g. gas, nuclear instead of coal
- catalytic converters limit nitrous oxides
what does smoke pollution do to affect the body and the environment
causes an increase in small particles, particulates. They block sunlight causing global dimming and damage the lungs when breathed in
What is smog
- what does it do
lots of particles of smoke and chemicals
- forms a haze of small particles and acidic gases
What are the three main reasons for deforestation
- grow foods
- rear cattle
- crow crops for biofuels
what are four negative effects from deforestation
- burning trees increases CO2 released into the atmosphere
- less trees reduce amount removed
- decomposers release CO2 when the trees decay
- loss of biodiversity
What is peat
plant material that cannot decay completely due to the acidic, anaerobic conditions
What are peat bogs used for
- have unique ecosystems
- burned as fuel
why is peat not sustainable as a fuel
it is produced very slowly and is being destroyed faster than it is being made
how is CO2 removed from the atmosphere
photosynthesis, dissolved in oceans and lakes
how is CO2 and methane added to the atmosphere
- respiration, burning fuels, decay
- rice and cattle farming
What is the greenhouse effect
- energy is transferred to the Earth from the Sun
- energy gets reflected to space
- the longer wavelength radiation cannot pass through the atmosphere so stays and is radiated back to Earth
- this causes the Earth to heat up
Why is the greenhouse effect necessary
to keep the Earth’s surface at a suitable temperature
What are some effects of global warming
- rising sea levels
- climate change
- ice caps melting
more unpredictable weather events
what are some effects of climate change
- loss of habitat
- changes in distribution
- changes in migration patterns
- reduced biodiversity
what environmental factors affect distribution of animals
- water scarcity
- temperature
- concentration of gases in water
Whata re the three types of environmental changes
- seasonal changes
- geographical changes
- result of human interaction
What are some examples of seasonal environmental changes
- temperature
- amount of rainfall
- sunlight hours
- water scarcity
What are some examples of geographical environmental changes
- soil structure and pH
- altitude
- saltiness of water
- water availability
What are some examples of environmental changes caused by human interaction
- maintaining / destroying rain forests
- acid rain
- pollution
- global warming and climate change
- conservation measures
What are some negative effects of migration of species
- affects biodiversity of areas
- new type of predator or pathogen can be transported and cause lots of harm
How can breeding programmes help endangered species
- what are some issues with this
- increases population of species
- they often do not have a proper habitat and so must remain in captivity, must prevent inbreeding
What are 5 ways we can maintain biodiversity
- breeding programmes for endangered species
- protection and regeneration of rare habitats
- reintroduction of field margins and hedgerows
- reduction of CO2 emissions and deforestation
- recycling resources
how does protecting and regenerating habitats help maintain biodiversity
- more habitats for threatened animals
so that they are no longer having a reduced habitat
how does reintroducing field margins and hedgerows help maintain biodiversity
allows former species to continue living where they were
how does reducing CO2 emissions help maintain biodiversity
reduced climate change
how does recycling affect biodiversity
- pollution from waste and land used by landfill reduces biodiversity
how have governments reduced amount of landfill
introducing landfill taxes
What is a trophic level
the position of organisms in a food chain
What is on the 1st, 2nd, 3rd and 4th trophic level
1 - producers
2 - primary consumers
3 - secondary consumers
4 - tertiary consumers
How do decomposers break down dead matter
secreting enzymes into the environment, then small soluble food diffuses back into the decomposer
What is biomass
- how is it measured
the mass of material in an organism
- the dry m ass of biological material in grams
how is biomass passed through the food chain
by eating
how do we show amount of biomass at each trophic level
a pyramid of biomass
in a pyramid of biomass, where is trophic level 1
at the bottom
how does biomass vary at each level of the pyramid of biomass
the higher the trophic level, the less the total biomass
why does biomass decrease at each trophic level
- not all the plant or animal can be eaten
- some is passed out as waste
- some animals or plants die
- lots of biomass is used for respiration
- homostasis
approximately how much of the energy from the Sun is used for photosynthesis by plants and algae
around 1%
around what percentage of biomass is transferred to the next trophic level
around 10%
why is biomass lost in faeces
animals cant digest all the biomass that it ingests
- herbivores cannot digest cellulose
- carnivores can’t eat claws, bones, teeth etc.
How is biomass lost as waste
glucose is used for respiration
- excess proteins become amino acids, lost in urine
- movement requires energy
why is biomass lost for keeping a constant body temperature
biomass is used to get energy for warmth
why does the biomass of decomposers affect the pyramid of biomass
it is not usually included
what is food security
having enough food to feed a population
what happens when there is no food security
people suffer from malnutrition or starve
What are 6 factors affecting food security
- increasing birth rate
- changing diets in developed countries
- new pests and pathogens
- environmental changes
- cost of agriculture
- conflicts
how does an increasing birth rate affect food security
more people means more food needs to be produced
how do changing diets affect food security
people in richer areas always want new foods
- this must be transported around the world
- this deprives people in the poor area of food
how do new pests and pathogens affect food security
kills or damages foods and reduces yield
how do environmental changes affect food security
droughts and flooding affect farmland
how does the rising cost of agricultural inputs affect food security
GM crops are produced, and this raises costs meaning farmers can’t afford as much
How does conflict affect food security
rising food prices, damaged infrastructure
what are 3 sustainable ways of producing food
maintaining soil quality
- looking at efficient ways of producing food
- taking care of fish stocks in oceans so they do not run out
how could food production be more efficient (food chains)
having a shorter food chain so less biomass is lost
how can we reduce biomass lost by animals such as pigs
- controlling the temperature of surroundings so less biomass is wasted for warmth
- limiting movement so less respiration happens
What are the benefits and drawbacks of intensive farming methods indoors, over rearing them outdoors
-control temperature
- reduce movement
- fit more in a smaller space
- no dependency on weather
- easy for disease to spread
- have to pay for lighting and heating
how is intensive farming done modernly
with lots of space for animals to roam, but indoors under ideal conditions
How are fish farmed
- how is this good
live in cages and fed from ground up wild-caught fish, specially bred for fast growth
- helps protect wild stocks, produces cheap food
what is the issue with overfishing
fish take time to grow, and they are killed before they fully grow, meaning there are no fish to breed and replace the dead
how is the issue of overfishing tackled
fish quotas reduce amount of fish caught
- bans on fishing in the breeding season
- large fishing nets that only trap grown fish - others can escape freely
why are GM crops used instead of normal crops
added nutritional value or greater yield
What are two ways biotechnology is used for sustainable food production
- GM crops
- genetic engineering
What is one way genetic engineering is used to help people
grow lots of insulin using bacteria, that can be used for people with diabetes
how is mycoprotein produced
- a fungus (Fusarium) reproduces on glucose syrup in special containers
- biomass is harvested and purified
- this can be shaped in many ways
