B18: Biodiversity And Ecosystems Flashcards
(31 cards)
What is biodiversity?
A measure of the variety of all the different species of organisms on earth
How has the increasing human population impacted the land?
Land used for farming, quarries, housing etc has destroyed habitats and reduced biodiversity
What happens if waste isn’t properly handled?
Pollution and future pollution is caused
How does pollution occur?
From landfill and toxic chemicals (e.g. pesticides and herbicides)
What effect does pollution have on the environment?
Kills plants and animals which reduces biodiversity
How is acid rain formed?
Fossil fuels are burned.
Sulfur dioxide is formed.
It dissolves in rainwater and reacts with oxygen and forms acid rain (pH 2.0)
What are the effects of acid rain?
Kills leaves, buds, flowers, fruits. Makes bodies of water acidic.
How do particulates from smoke pollution impact the earth?
They cause a dimming effect that could lead to cooling of the earths surface
What impact does smog have?
A haze of small particulates (causes dimming) and acidic gases.
What are the 3 main reasons for deforestation?
Land to grow food, to rear more cattle and to grow crops for biofuel.
What negative effects does deforestation have?
Increases carbon dioxide in the atmosphere and reduces biodiversity
How does pear destruction impact the environment?
Loss of biodiversity and the decay/burning of peat releases carbon dioxide into the atmosphere
What are biological consequences of global warming?
Loss of habitat, rising sea levels/temperatures, changes in the distribution of species.
What is an example of how seasonal changes impact animal distribution?
Some animals migrate to avoid the cold
What are examples of seasonal changes?
Temperature, amount of rainfall, hours of daylight
What are examples of geographical changes?
Altitude, saltiness of water, availability of water
What negative changes can occur as a result of human activities?
Global warming, pollution, acid rain
What positive changes can occur as a result of human activities?
Maintaining rainforests, reducing pollution, species conservation
What 2 things make breeding programmes difficult?
Not reproducing easily and loss of habitat to breed in
What are trophies levels?
The positions of organisms within a food chain
What are trophic levels 1,2,3&4?
1= producers
2= primary consumers
3= secondary consumers
4= tertiary consumers
What is the amount of biomass in the organisms at each trophic level less than the previous level?
Not all parts of organisms are eaten by the stage above. Some biomass is lost in waste, some is used to produce energy for movement, respiration and temperature control.
What happens to excess protein in an animal?
It’s broken down into amino acids
What 2 things can affect food security?
Increasing birth rate and a change in diet
