biological factors affecting food security Flashcards Preview

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Flashcards in biological factors affecting food security Deck (48)
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1
Q

arable farming

definition

A

When crops are grown.

2
Q

bioethanol

definition

A

Ethanol that has been produced from crops. Bioethanol is an example of a biofuel.

3
Q

compost

definition

A

Decayed organic matter which can be used as a plant fertiliser.

4
Q

eutrophication

definition

A

‘Hyper-nutrition’ resulting from fertiliser pollution of aquatic ecosystems.

5
Q

What was the industrial revolution?

A

The process that transformed manufacturing from handmade to machine-made, mass-produced goods using water, steam and coal power transported by canal, rail and steamship. Britain was the first country to have an Industrial Revolution.

6
Q

intensive farming

definition

A

Farming methods that usually involve monoculture (growing one crop) and using pesticides and fertilisers to improve crop yield.

7
Q

manure

definition

A

Animal dung (solid waste) used as fertiliser.

8
Q

monocultre

definition

A

Growing one type of crop.

9
Q

non-renewable

definition

A

A resource that cannot be replaced when it is used up, such as oil, natural gas or coal.

10
Q

over-fishing

definition

A

To catch fish in such high numbers that species struggle to survive.

11
Q

pesticide

definition

A

A chemical used to kill pests, such as the potato cyst nematode which is a pest that destroys potato crops.

12
Q

sustainability

definition

A

The ability to keep something going over time without harming people or the environment.

13
Q

What is the theory of evolution?

A

A theory put forward by Charles Darwin that all living creatures that exist today, including human beings, have evolved over a period of millions of years from more primitive life forms.

14
Q

What is food security?

A

Food security is a measure of the availability of food required to support people of a household, region, country or any specified area. It is a measure of how much food there is, if it is of suitable quality and whether people can access it.

15
Q

Food security is reduced by:

A
  • The increase in human population, as birth rates are increasing and many people have better access to medical care.
  • Changing diets eg people starting to eat more meat in newly developed countries like China. This means that food resources are transported to be sold from areas which need them, especially meat and fish.
  • New pests and pathogens that attack crops and farm animals.
  • Environmental changes such as global warming.
  • Increased costs of farming.
  • Armed conflicts.
16
Q

Intensive farming

overview

A

Intensive farming uses machines, fertilisers, man-power and high-yield crops to maximise the amount of food produced. Farmers growing arable crops often specialise in growing only one crop to maximise their profits. This is called monoculture. It can quickly reduce key nutrients in the soil and lowers biodiversity.

17
Q

Intensive farming

Hedgerows

A

Hedgerows have been removed from many fields to make them bigger and easier to tend to by big machines. This also reduces biodiversity. Crops are often sown, treated and harvested by machines which create pollution, and fertilisers are added to fields in larger amounts which can cause eutrophication.

18
Q

Intensive farming

Livestock

A

Intensive farming can also mean keeping livestock in smaller pens with regulated temperatures. This reduces the energy they need for movement and temperature regulation and so maximises their size and yield. Some animals are fed high protein foods to increase their growth. They are often fed antibiotics in their food to prevent diseases. Many scientists think this is leading to antibiotic resistance in bacteria.

19
Q

Advantages of intensive farming practices

A
  • Higher yields
  • Cheaper food for the consumer
  • More efficient use of food
  • Quality control easier
20
Q

Disadvantages of intensive farming practices

A
  • Reduction in biodiversity
  • Creates pollution
  • Risk of antibiotic resistance
  • Considered unethical by some people
21
Q

Why many people object to intensive farming

A

Many people object to intensive farming because it reduces biodiversity and increases pollution. More recently some farms have become organic to address this.

22
Q

Organic farming

A

Organic farmers do not use machines to the same extent as intensive farming. They do not apply pesticides to their crops and use natural fertilisers such as compost and manure. They rotate their crops to avoid monoculture.

23
Q

Intensive farming of animals

A

The demand for more meat has resulted in increased intensive farming of animals such as cattle, pigs and chickens. This has an impact on food security because animal farming wastes more energy because the food chain is longer. It is much more efficient to grow crops so more people can be fed per area of land. In addition, farmed animals are often fed crops which could be consumed by humans.

24
Q

Farming techniques

Negative impact of pathogens and pests

A

Pathogens including bacteria, fungi and viruses may infect the crops or farm animals and will reduce the yield of crops and reduce the food availability for the human population. New pathogens may reduce yields dramatically as the crops or animals may not be resistant. New diseases may lead to crop failure and reduced food production. Also new pests such as insects may damage the growth of crops, reducing yield and food security.

25
Q

Sustainability and farming

A

Sustainability means maintaining the needs of the human population into the future. This includes food security and fuel for vehicles and industry. Fuels such as diesel and petrol made from crude oil are non-renewable and are running out. An alternative fuel is biofuel such as bioethanol which is made by fermenting sugar from corn or sugar cane. Therefore these biofuel crops provide a renewable fuel. They have a negative impact though, as they are often grown on land which could be used for growing crops for food.

26
Q

Farming techniques

Cost of agricultural inputs

A

Farming is expensive in terms of land costs, machinery, fuel and fertilisers. As costs increase, many farmers find it too expensive to continue farming so farms shut down and food production stops. This has a negative impact on food security.

27
Q

Biofuel

definition

A

A type of energy source derived from renewable plant and animal materials, eg ethanol (often made from corn in the United States and sugarcane in Brazil), biodiesel (vegetable oils and liquid animal fats) and biogas (methane from animal manure).

28
Q

arable farming

definition

A

When crops are grown.

29
Q

compost

definiton

A

Decayed organic matter which can be used as a plant fertiliser

30
Q

Pathogen

definition

A

Microorganism that causes disease.

31
Q

effect of sustainable fisheries on number of fish

A

Sustainable fisheries do not reduce the overall number of fish, because the number of fish that are caught and killed does not ever exceed the birth of new fish.

32
Q

Overfishing

A

At one point we thought that we could remove as many fish as we wanted from the oceans without any consequence. During this period, we drastically overfished some of our oceans and seas and reduced some populations to critically low numbers.

33
Q

Result of overfishing

A

Some scientists think that as much as 85% of the world’s fish populations have been overfished. Common examples are cod in the North Sea and sole in the Irish Sea and English Channel. Overfishing can cause a critical point in populations that means certain species cannot ever recover and will become extinct.

34
Q

Addressing overfishing

A

To address overfishing many countries are adopting a more sustainable strategy for fishing and have introduced fishing quotas which limit the amount of fish that can be caught and killed from specific species. The size of the gaps in fishing nets has also been increased to ensure that juvenile fish can reach reproductive maturity and have offspring before being caught.

These practices have meant that many fish populations are now recovering.

35
Q

Positive effects of the greenhouse effect

A

Without the greenhouse effect the mean temperature on Earth would be -18°C and there would be very little or no life. So the greenhouse effect itself is a good thing. The greenhouse effect traps some of the energy from the Sun, which keeps our planet at a suitable temperature for life.

36
Q

Problem with our increased release of greenhouse gases

A

The problem is that our increased release of greenhouse gases is causing an increase in the greenhouse effect called the enhanced greenhouse effect. This is leading to global warming.

37
Q

Carbon dioxide increase since the industrial revolution

A

Carbon dioxide, water vapour and methane are amongst the most common greenhouse gases. Since the start of the Industrial Revolution in about 1750 the levels of carbon dioxide have increased by 40%.

38
Q

Global warming

overview

A

Global warming is the increase in the mean temperature of the Earth. The ten hottest years since records began have been in the last 30 years. The mean increase in the last 100 years has been less than 1°C. This might seem small, but is enough to have devastating consequences on many species in different parts of the world.

39
Q

Global warming

Relationship between carbon dioxide and the earth’s mean temperature

A

As the percentage of carbon dioxide in our atmosphere has increased so has the Earth’s mean temperature

40
Q

The consequences of global warming are:

A
  • melting of the polar ice caps
  • the rise in sea level may one day threaten many cities such as London, New York and Amsterdam
  • weather patterns will change with more unusual weather
  • animals will migrate towards the poles to find habitats with suitable temperatures
  • tropical diseases may become more common in other regions, such as Europe
  • change in distribution of pests that attack crops, which will have an impact on food security in some areas
  • many species will become extinct
41
Q

Monoculture is the growing of what?

A

Monoculture is the growing of one crop per field. It is more effective and profitable for the farmer.

42
Q

What is a pathogen?

A

A disease causing organism

43
Q

What can the overuse of fertilisers in intensive farming lead to?

A

Eutrophication

44
Q

Why do farmers keep cattle in small pens?

A

To reduce energy wasted in movement and increase yield

45
Q

How have some countries tried to preserve fish stocks?

A

Quotas

Some countries have tried to preserve fish stocks by the introduction of quotas. This will restrict the amount of fishing and protect fish species.

46
Q

What types of fishing nets have been introduced to protect fish?

A

Fishing nets have been introduced with larger gaps. This means that younger, smaller fish can have offspring before being caught.

47
Q

What are the consequences of global warming?

A

Melting of the polar ice caps and increased sea levels

48
Q

An increase in the greenhouse gas methane will do what to the temperature of the earth?

A

Increase