Human influences on the Environment Flashcards
What are the biological consequences of the release of sulfur dioxide and nitrous oxides?
Acid rain is caused
It damages the leaves, buds, flowers and roots of trees and other plants
It acidifies lakes and rivers, making them inhabitable for certain marine organisms
It causes minerals to be leached out of the soil into lakes which are toxic such as aluminium causing the death of fish, or which are fertilisers causing eutrophication
What are the biological consequences of the release of carbon monoxide?
While it does not damage plant-life, it binds readily to the haemoglobin in animals (including humans), meaning the blood oxygen carrying capacity is reduced potentially causing suffocation or organ failure
It also contributes to climate change
What are the most important greenhouse gases?
Water vapour
Carbon dioxide
Methane
Nitrous oxides
CFCs
What are the consequences of global warming?
Glacial melt - Increased sea levels and flooding
Ocean acidification - Coral bleaching
Extreme weather events - More frequent drouts and super storms
Loss of biodiversity as habitats are lost, conditions become unsuitable for certain species and food chains are disrupted
Increase in migration of species to new places causing the spread of pests and diseases
What are the biological consequences of the pollution of water by toxic chemicals?
Agricultural runoff can cause toxic chemicals to go into the water
These chemicals, which cannot be easily broken down by organisms are absorbed by plants and invertebrates building up in their tissues overtime
This is called bioaccumulation, and any predators who eat them will also ingest these compounds and levels of the chemicals will build up over time - eventually humans may eat the marine organisms and ingest the chemicals
Eventually, the toxins will build up to dangerous levels within organisms, causing their death of failure to breed and disrupting food chains
What are the biological consequences of the pollution of water by untreated sewage?
Sewage provides a good food source and minerals for decomposing bacteria, which rapidly multiply and deplete the levels of oxygen dissolved in the water
This lack of oxygen eventually results in the death of aqautic organisms - this is a form of eutrophication
What are the biological consequences of eutrophication caused by leached minerals from fertilisers running into bodies of water?
Excessive nutrients and minerals from fertilisers run in to the water
Aquatic plants and algae flourish and bloom
Algae blooms on the surface prevent light from reaching aquatic plants, causing the rate of photosynthesis to decrease and the oxygen levels to reduce
The increase in dead plant matter causes an increase in aerobic respiration in decomposers, further causing levels of oxygen to fall
As a result of low oxygen levels, marine organisms will die
What are the consequences of deforestation?
Habitats are destroyed and biodiversity is decreased
Soil is eroded due to the loss of stabilising roots, and all the nutrients that would otherwise have been used by trees are washed away by rain and leached into lakes and rivers causing eutrophication
The loss of nutrients also makes it very hard for plant life to regrow in the area
Less trees means less transpiration which causes lower levels of rainfall and drouts
A lack of trees also means less stable soil which can be easily washed away, decreasing the protection against flooding
Finally, the carbon cycle is disrupted as less carbon dioxide is being taken out of the atmosphere by trees, causing increased levels of atmospheric carbon dioxide
This, coupled with the burning of trees after them being cut down which also increases levels of carbon dioxide, contributes to climate change
