B18 Flashcards
(14 cards)
What is biodiversity?
It is the measure of the variety of all different species of organisms on earth.
What are the impacts of population growth on land and resources?
Buildings, for farming, for quarrying and for landfill.
How can pollution occur?
It is due to waste and chemical materials being improperly handled. It occurs on land and in water from sewage and fertilisers. It reduces biodiversity.
How is acid rain caused?
When fossil fuels are burnt, acid gases are formed. This is due to sulphur impurities, which lead to sulphur dioxide being released which dissolves in rain water and causes acid rain.
What are the 3 reasons for deforestation?
To grow staple foods and ingredients, to rear more cattle and to grow crops that can be used to make biofuels.
What are peat bogs?
They are made out of plant material that cannot decay due to acidic and lack of oxygen.
What is peat used for?
Burnt as a fuel and used by gardeners to improve the properties of the soil.
How can biodiversity be maintained?
Breeding programmes, protection of rare habitats, reintroductions of hedgerows, reduction of deforestation and recycling.
What are trophic levels?
The positions of organisms within a food chain.
How is biomass lost?
Due to not all the ingested material being absorbed, some lost as waste products like carbon dioxide and water in respiration, urea in urine and feaces.
What are 7 factors affecting food security?
Increasing birth rate, changing diet, new pests, environmental changes, cost of agricultural inputs, conflicts and a sustainable solution.
How can food production be made more efficient?
By restricting energy transfer from food animals to the environment. By limiting movement and controlling temperatures this is done.
How can we maintain the oceans?
We need to keep fish stocks at a level where breeding continues. This is done by control of net size, quotas and modern biotechnology.
What does fusarium fo?
It is a fungus which produces mycoprotein which is good for vegetarians. It is grown on glucose syrup in aerobic conditions and the biomass is harvested and purified.
