How Humans Can Affect The Environment Flashcards
What is meant by non renewable
Something which cannot be replaced when it is used up
What is produced when goods are produced
Industrial waste
What is reduced when humans build, quarry, farm and dump waste
Reduce the amount of land available for animals and plants
What is the the increasing population affecting
The ecology of the earth
What is ecology
The scientific study of the relationship between living organisms and their environments
What do waterways become polluted with
Sewage, fertilisers and toxic chemicals
What contributes to acid rain
Air with smoke and gases such as sulfur dioxide
What do humans pollute the land with which is then washed into water
Toxic chemicals such as pesticides and herbicides
Why must sewage be treated
To remove gut parasites and toxic chemicals or these can get onto the land
What does sewage contain
Human body waste and waste water from our homes
Why do landfills cause pollution
Large amounts of household and industrial waste at eplaced in the landfill and toxic chemicals leak out which is hazardous
Farming methods can …….. ……….
Pollute the land
Why are herbicides and pesticides bad
They are sprayed onto crops and can get into the soil and into the food chain. Eventually many of them are washed into rivers
Why are fertilisers used by farmers a problem
They. Can be washed into and pollute rivers
What causes water pollution
Herbicides, pesticides and chemical fertilisers all get washed into rivers and streams
Fertilisers and untreated sewage can cause a high level nitrates in the water
Toxic chemicals from landfill also leak into the waterways and pollute water, killing organisms such as fish
What do power stations and cars release
Acidic gases
Which gases are produced from burnin fuels
Sulfur dioxide and acidic gases
What is the current world population
7 billion
How are acidic solutions formed
When sulfur dioxide dissolves in the air
Why can sulfur dioxide pollute areas where the gas was not produced
The solutions produced fall as acid rain and the gas is blown by winds before it dissolves
What can acid rain do
Kill organisms, trees become damaged if the leaves are soaked in acid rain for a long time
How does acid rain affect soil ph
It changes the soil ph which damages roots and may release toxic minerals, aluminium Iona spare released which also damages organisms in the soil and in waterways.
Enzymes which control reactions are sensitive to ph
How are birds affected by acid rain
The rain kills trees which means birds loose habitats and food
Why does deforestation occur
The need for timber and to provide land for agriculture
Crops are grown to produce ethanol based biofuels
There can be increases in cattle and rice fields for fuel
What 3 effects has deforestation caused
It increased the release of co2 into the atmosphere due to burning of trees or decay of wood by microorganism
Reduced the rate at which co2 is removed from the atmosphere by photosynthesis
Reduced biodiversity due to loss of food and habitats
What does cattle and growing rice produce
Methane
What does the destruction of peat bogs cause
It releases co2. This occurs because the peat is removed from the bogs and used in compost for gardens. The compost is decayed by microorganisms
What can peat free compost prevent
The destruction of peat bogs
Which process causes co2 to be released from peat
Decay by microorganisms
What does co2 dissolve into
Oceans, rivers, lakes and ponds
How is co2 sequestered
Co2 is removed from the air by plants in photosynthesis and by dissolving in oceans, lakes and rivers
What do greenhouse gasses cause
Greenhouse effect
What is the greenhouse effect
The trapping of infrared radiation from the sun as a result of greenhouse gases such as co2 and methane, in the earths atmosphere. The greenhouse effect maintain the surface of the earth at a temperature suitable for life
What does the greenhouse effect cause
Global warming
What effects does an increasing temperature have on the earth
Big changes in the earths climate
Cause a rise in sea level due to ice caps and glaciers melting
Reduced biodiversity
Changes in the migration patterns eg birds
Changes in the distribution of species
What are 2 types of biofuels
Ethanol based fuels and biogas
How can ethanol based fuels be produced
Fermentation
How do microorganism produce ethanol
They respire anaerobically using sugars from crops as the energy source
How is glucose produced from maize starch
The action of carbohydrase
How is yeast used in the production of ethanol
The glucose and sugar cane juices are fermented by yeast
How is the ethanol extracted from the glucose/sugar cane/yeast mixture
Distillation
Why is ethanol carbon neutral
The only co2 used for photosynthesis by the crops is returned to the atmosphere when the ethanol is burned
How is athanor produced from starch
Digestion of starch to sugar by carbohydrase
Fermentation by anaerobic respiration of yeast
Distillation
What has is mainly biogas
Methane
How is methane for biogas produced
During anaerobic fermentation by bacteria
What can be broken down in biogas generators
Plants and any waste materials containing carbohydrate
What conditions do generators have
Ideal conditions for bacteria to reproduce and ferment the carbohydrates
Maintained at a suitable temperature in oxygen free conditions
Some are designed to mix contents
Buried in the ground for insulation or have insulating jackets
What do commercial generators
They use waste from sugar factories or sewage works
What does biofuel provide energy for
Heating
Why is it efficient for us to eat plants than animals
The shorter the food chain, the less energy will be wasted.
How could we produce more efficient meat
Prevent the animals from moving so it doesn’t waste energy on movement, but this is cruel
Keeping the animal in warm sheds so it doesn’t use as much energy from food to maintain its body temperature
What does sustainable food production involve
Managing resources and finding new types of food such as mycoprotein
How are fishermen helping make food production sustainable
Can only remove a strict allocations of fish per year, a quota
Must use certain sized nets to avoid catching small young fish
What is mycoprotein
A food based on the fungus fusarium that grows and reproduce rapidly. It means protein from fungus
What is used to produce mycoprotein
Fungus fusarium
How is fusarium grown
Aerobically on cheap sugar syrup made from waste starch and the myoprotein is harvested
Where can microorganisms be grown
On a large scale in industrial fermenters
What do industrial fermenters have
An air supply providing oxygen for respiration
Stirrers or gas bubbles used to keep the microorganisms spread out and to provide an even temperature
A water cooled jacket around the outside as the respire get microorganisms release energy which heats the contents
Sensors to monitor both ph and temperature
Which 3 human activities can affect the global environment
Deforestation, causing increased levels of co2 in the atmosphere
Increases in rice growing and rearing cattle result in more methane
Building dams p, to store water in reservoirs, causing loss of habitats, drying out rivers below the dams and reduces in fertile lands to grow crops
Why do scientists come to different conclusions when considering the same data
Explanations depend of individual opinions of the scientists and can be biased
What do some people believe about global warming
That it is part of the earths natural cycle
