B18 Flashcards
(26 cards)
what is biodiversity
a measure of the variety of all the different species of organisms
what is the benefit of a high biodiversity
helps to ensure stability of ecosystems
how do humans reduce the amount of land available for animals and plants
building
quarrying
farming
give some ways humans pollute
water ways with sewage fertiliser and toxic chemicals
air with smoke and gases
how are herbicides and pesticides damaging biodiversity
when they are spraid onto crops, they enter the food chain and it may accumulate
how does fertiliser and untreated sewage pollut
high levels of mineral ions such as nitrates stimulate rapid growth of algae and water plants
competition for light increases as many plants die
microorganisms feed on dead material so oxygen levels deplete in water
what is a carbon sink
where carbon dioxide is stored such as plants and water
what are some environmental changes which impacts life
temperature, rainfall, light
what can the changes be classified as
seasonal geographic or human interaction
how can we combat climate change
maintain rainforests
reduce water pollution
monitor water pH
how are endangered species restored
breeding programmes
why can breeding programmes be difficult
many rare animals or plants do not reproduce fast
the habitat the organism needs to survive may be lost
what are some examples of rare habitats
coral reefs
heathland
how can farmers help maintain biodiversity
allowing hedgerows and wild plants to grow
how has the government helped maintain biodiversity
introduced laws to protect specific eco systems
working to reduce carbon emissions
what is biomass
mass of living material in plants and animals
what are trophic levels
represent an organisms position in a food chain
what percent of biomass from each trophic is transferred to the levekl above
10%
how can biomass be lost
urine
energy from respiration
faeces
what are some factors affecting food security
increasing birth rates
changing diets in developed countries
new pests or pathogens
why is it more efficient to eat plants
the shorter the food chain, the less energy wasted
how can humans produce more meat efficiently
prevent animal from moving
keeping animal in a warm shed
how and why do fishermen maintain fish stocks
fish stocks in the ocean are declining
fishermen only remove a strict allocation of fish each year
fishermen use certain sized nets
how else can people produce sustainable food
genetically modified crops
fermenters
