Human Impact on the Environment : Food security

Food security refers to access, by people at all times, to adequate, safe and nutritious food for a healthy and productive life.

Factors influencing food security include the following:

Exponential growth of the human population

There are two types of growth curves to study when we talk about populations. The first one forms a J shaped curve and is called the exponential growth curve, while the second has an S shaped graph and is called the logistic growth curve.  In a logistic growth, populations eventually even out over the carrying capacity of an environment and form a natural increase and decrease over time. In contrast to this type of interaction, in an exponential growth form, after an initial extreme increase there is a sudden crash of the population. Since we are mammals , we classify ourselves as logistic populations, but so far the Scientific Evidence suggests we are the exponential growth form.

The earth allots 4.4 acres of biologically productive land to every person, but humans use 6.7 acres per person. We are severely overshooting our ecological budget. Global food production cannot keep up with the current demands. It is estimated that Global food production must increase 70% by 2050 to meet our needs. Currently almost 1 billion people suffer from chronic hunger. What hunger means :

  • Children suffering from severe malnutrition are 9x more likely to die early
  • Hunger increases a country’s risk of democratic failing, rioting, violence and civil conflict

How can we fight this ? Through investments!

  • Growth in agriculture is on average at least twice as effective in reducing poverty as growth in other areas
  • Investments that provide women equal access to land, water, seeds, training and funding in agriculture can increase farm yields by up to 30%

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Droughts, fires and floods

Climate change has led  to more frequent and severe droughts and floods. Droughts result in crop losses and livestock death, which reduces the available food in the area. Floods cause extensive damage in a short period of time and decreases the amount of farmland available to grow crops. People also usually loose their homes, possessions and economic security.

80% of the worlds cultivated area is rain fed.  70 % of the world water withdrawal is used for agriculture. Only 2.5% of the worlds water is fresh water.

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Poor farming practices

1 in 3 people work in agriculture worldwide. 60% of child labourers work in agriculture. Small holders produce 80% of the food consumed in developing countries. 38 % of the worlds land is used for agriculture and 12 % of the worlds land is used for crop production.


The growing of one type of crop over large areas of land year after year is called monoculture. This form of farming practice depletes nutrients and water supplies and has a negative impact on topsoil.

Pest control


Pesticides (toxic chemicals) are used to kill pests that compete with humans for food. These are often expensive, which increases the cost of crop production and reducing availability of these food crops to people who cannot afford it. Farmers who have realised this are changing over to biological control of pests, which uses natural predators/parasites to get rid of pests.


Only the top 1,5 meters of topsoil contain the nutrients that plants require for growth. The tilling of the soil between plantings and heavy rainfall causes much of the topsoil to be lost, which reduces crop yields.

Use of fertiliser

Due to the nutrient loss that topsoil incurs, it is important to replace it. To do this farmers use both inorganic and organic fertilisers. Fertilisers are expensive, which increases costs of productions and the poor cannot afford the crops again.

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Alien plants

Blue gum trees use up to 900 liters of water a day.

Blue gum trees use up to 900 liters of water a day.

Alien plants out compete indigenous plants because they have no natural predators, growing rapidly and invading land that could be used to grow crops.

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Loss of biodiversity

Genetic resources for food and agriculture are extreme importance for food security, nutrition and livelihoods. However, biodiversity , and in particular genetic diversity, is being lost at an alarming rate. 14 of the approximately 30 domesticated mammal and bird species provide 90% of human food supply from livestock. Of the 8300 breeds 8% is already extinct and 22% is at risk of becoming extinct. Fish provide about 3 billion people with almost 20% of their intake of animal proteins.  Plants account for 80% of the human diet.

  • 30 000 terrestrial plants are known to be edible
  • 7000 are cultivated of collected by humans for food
  • 30 crops feed the world
  • 5 cereal crops provide 60% energy intake of the world population

Threats to genetic diversity include:

  • Climate change
  • Loss of natural habitats
  • Environmental degradation
  • Increasing population pressure
  • Change in consumer demand
  • Development and use of only a few species, varieties and breeds

Another problem is the loss of pollinators like bees. 90% of vegetable crops depend on honey bees for pollination.

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Genetic engineering

All breeding leads to genetic changes, but genetic engineering is the targeted manipulation of a plant or animal’s DNA to modify specific traits. It can involve tweaking a species’ own genes or adding genes from another species. GMO’s are leading to the death of pollinators like bees.

Genetically engineered crops are controversial for a variety of reasons. On the one hand there are advantages and on the other disadvantages.

Advantages of GMO’s:

  • In crops it can enhance the taste and quality, reduce the maturation time, increase the nutrition, yield and stress tolerance and improve resistance to disease, pests and tolerance.
  • In animals in can increase their disease resistance, productivity and hardiness, as well as increasing yields
  • In this way in can increase food security

Disadvantages of GMO’s

  • Safety – impact to humans and the environment is only now becoming clear as several studies has shown that GMO use leads to sterility in the 3rd generation
  • Due to intellectual property, not all people have access to these products, and a few companies are dominating the market
  • There are many ethical objections, related to cultures and religions, in using animal genes in crops.

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Food wastage

Wastage could occur during the storage, production and processing of food. Wastage includes food thrown away and food not eaten. Wastage increases the prices of food to consumers and could reduce food security in a country.

Up to 1/3 of all food is lost or wasted worldwide. The most wasted food are those the people need the most. Nearly ½ of all fruits and vegetables are lost or wasted. The food currently lost in Africa alone can feed 300 million people. 25% of food losses occurs during the pre-harvest phase in developing countries. 12 % of food losses happens during the harvesting phase in developing countries. 40% of food losses in developing countries are a result of inadequate storage.

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8 thoughts on “Human Impact on the Environment : Food security

  1. Pingback: Human Impact Project: – Site Title

  2. It is frightening, as I watch the newsy, and can already see how the ocean is being damaged irreversibly. Fish are dying everywhere in massive quantities. Not only that. I regularly go diving off the coast of South Africa, and the reefs are dying. We just do not have the diversity there used to be. The coral is bleached, even the species we find are changing. This is truly a GLOBAL disaster.


  3. “Fish provide about 3 billion people with almost 20% of their intake of animal proteins. ”

    Yes, and as a result of radiation releases from the nuclear power plant in Fukushima Japan, ongoing for over 5 years now, life in the Pacific Ocean is decreasing drastic-ly. Given the half life of Cesium 137 and the inability of scientists to stop the flow of radiation from the melted down reactors, this scenario will continue to worsen for decades. Those radionuclides return to oceanic circulation once contaminated fish die, to be taken up once more by other organisms. This affects the entire food chain. And of course, all oceans are connected so, though it will take some time, we can expect the contamination to eventually affect oceans around the globe.

    Those 3 billion people will likely eat contaminated fish as long as there are fish to catch, leading to cancers, and birth defects in later generations.

    This is a nightmare scenario, and a strong argument against nuclear power.

    Liked by 1 person

  4. You said above: “38 % of the worlds land is used for agriculture and 12 % of the worlds land is used for crop production.”

    What are your definitions of “agriculture” and “crop production”?
    Thank you.


  5. At #engineeredfood we are educating young people on the pro’s and con’s of GM food. Food security is a major issue that GM food can help fix, however in the current state most GM foods are being used to feed livestock and only a small amount is accessible for humans in 1st world countries. We need to be getting these genetically modified crops to countries who really need the crops to resist harsh conditions.


    • This is a very difficult issue to address. I live in a country where 90% of the food we eat is GM food. None of them are labelled as GM though so we have no choice about buying it. Many of my friends have had to undergo fertility treatments before they could conceive. Whether it is due to GM food, using the pill or something else isn’t clear. I have read up on it though and both GM and long term use of birth control could lead to sterilisation. What good would it do to feed the starving just to see their children die out anyway?

      Liked by 1 person

      • There is an unholy alliance between farming giants like Monsanto and the FDA which results in Monsanto getting approvals for GMO products with no real oversight.
        There are serious disease states linked to GMO products such as bt-Corn and others. These products may well lead to a significant decrease in the human population in areas which must consume them. Given that organizations of mega wealthy and influential people, such as the Club of Rome, have published goals which include reducing the world population down to around 500 million, one wonders whether GMO products are so unhealthy by accident or not.

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