1. Secondary 4 Pure Geography
Human Geography (2235/2)
Sec 4 Chapter 14
Developments in Food Production
Enquiry questions:
1) What are the effects of intensifying food production?
2) What are the effects of genetically modified (GM) food crops?
3) Will such developments in food production ever over food shortages?
Content:
Continuing intensification of food production activities (irrigation and use of chemicals) on
water and soil quality.
Development of genetically modified food crops
o Benefits (economic and regional development)
o Threats (health and native species)
Learning objectives:
Be able to evaluate the effects of continued intensification of food production activities on
water and soil quality.
Be able to discuss the positive and negative effects of genetically modified food crops.
Be able to assess whether developments in food production will overcome the problems of
starvation and malnutrition.
Key terms:
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2. Secondary 4 Pure Geography
Human Geography (2235/2)
Sec 4 Chapter 14
What are the effects of intensification of food production?
Section I: Introduction
In the previous chapter, we learn different methods that farmers use to increase output.
However, there are negative impacts of the methods used by the farmers.
Section II: Effects of intensification
1) Effects of increasing irrigation
a) Salinisation of soil
Salinisation refers to the building up of salts within the soil.
Water that has been used to irrigate the soil evaporates during the dry season that follows
the heavy monsoon rains.
This causes salts to form a pan within the upper layers of the soil which is poisonous to
crops and lethal to plant life.
Salinisation can also happen in areas where dams are constructed for irrigation.
This leads to sediments and minerals being trapped in the reservoir behind the damn.
When the water in the reservoir is used for irrigation, it will increase the salinity of the soil.
As such, over time, the salt concentration in the soil may be too high for most crops.
Salinisation also tends to occur in arid regions and coastal areas.
The main source of irrigation is groundwater in arid regions, which is rich in salts.
As water is pumped out from underground, the salinity of the soil increases.
In coastal areas, salt water from nearby seas seeps into groundwater as water is drawn up.
For example,
o globally 58% of irrigated land shows rapid decrease in productivity while 6% of
agricultural land in India has now turned barren.
b) Waterlogging
Waterlogging occurs when farmers over-irrigate the land or use large amounts of irrigated
water to wash excess salt from the land to reduce salinisation.
Hence, air and nutrients that crops need cannot reach their roots.
As such, vegetation turns yellow, growth is stunted and thin and eventually die.
This decreases output and food production.
For example,
o waterlogging affected 6 million of the total 18 million ha of irrigable area in Pakistan.
o globally about 10% of all irrigated land suffers from waterlogging.

3. 2) Effects of increasing use of chemicals
a) Imbalance in soil nutrients
Chemical fertilisers are unable to supply all the nutrients required by plants.
In addition, they do not add humus to the soil.
Hence, the lack of humus1 may cause the soil to lose its fertility in the long run.
For example,
o 75% of Bangladesh’s agricultural land is losing its fertility due to prolonged use of
chemical fertilisers like urea and ammonium sulfate as well as substandard fertilisers.
b) Eutrophication
Excess fertilisers used in farms (in the hope for greater output) are washed by rain into
water bodies like rivers and lakes.
This causes rapid algal and plankton growth which prevents light from entering the water.
Aquatic plants cannot photosynthesise to replace the oxygen lost, hence oxygen level drops.
This cause the algae and plankton to compete for oxygen with aquatic creatures.
When the plants and animals die, the decomposition of dead matter depletes the oxygen.
As such, more animals and plants die from a lack of oxygen.
For example,
o every year, Japan is plagued by at least 50 toxic algal blooms caused by the
leaching of nutrients from fertilisers into water bodies.
c) Water pollution
Chemicals such pesticides and herbicides seep into groundwater and flow into nearby water
bodies such as rivers.
Chemicals in the water can harm or kill aquatic plants and animals.
People who drink such contaminated water may also get poisoned.
For example,
o the leaching of nitrates into underground water through leaching is also a hazard.
When consumed, babies may suffer from blood poisoning known as ‘blue baby
syndrome’. Children may suffer from hypertension and adults from stomach cancer.
o the distribution of drinking water from a damn near Rennes, France had to be
stopped by the public health authorities due to pesticide contamination.
1
Humus refers to the organic substance formed from decomposition of dead plants and animals. It is
irreplaceable and helps bind soil together, reducing barren soil disintegration.

4. Secondary 4 Pure Geography
Human Geography (2235/2)
Sec 4 Chapter 14
What are the impacts of GM food2?
Section I: Introduction
GM refers to the modification of genetic make-up of plants through artificial insertion of
genes from foreign source like plants or animals.
Green Revolution (GR) refers to cross-breeding of 2 plants with desired characteristics.
Section II: Benefits of GM food
1) Increases farmers’ incomes
GM food which are more resistant to pests, low rainfall and other problems can now be sold.
With so much crops destroyed in the past, the yield has increased, bringing in more money.
Farmers can also sell food that has been genetically modified to stay fresh for longer to
countries further away and earn more money, leading to regional development.
For example,
o the antifreeze gene from cold water fish (ie. salmon and cod) were introduced into
plants such as tobacco and potato to allow these plants to tolerate cold temperatures
that can kill sensitive seedlings.
o Bacillus thuringiensis (Bt) corn is a pest-resistant crop plant, having a gene inserted
from a bacterium Bt. As Bt is a natural pesticide, the Bt corn suffers less damage
from insects and fewer crops are damage, increasing output.
o over the period of 9 years between 1996 and 2004, farm incomes have increased by
over $19 billion or $27 billion inclusive of second –crop GM soyabean.
2) Increases food supply
The cultivation of Super Rice, a type of GM rice, produces double the output of normal rice.
This led to the decline in food prices and they are more affordable especially for LDCs.
This reduces the problem of malnutrition and improves people’s health.
The poor farmers also earn more income by selling it overseas, due to its long lasting ability.
Plants that are improved can now withstand drought or high salinity and hence open up
previously inhospitable places for food production.
2
GM food refers to food from plants that have been genetically altered to achieve certain qualities.

5. 3) Improves nutritional value of food
GM food crops such as Golden Rice has been enriched with beta-carotene to supplement
the lack of Vitamin A which causes blindness, in rice diets in LDCs.
Lack in Vitamin A in rice diets in LDCs has resulted in 1 million children dying every year
and 350 000 becoming blind.
Scientists are also exploring the use of GM food as a form of medicine or vaccine in LDCs.
For example,
o Vaccines in the form of bananas for easier storage and administration.
For many LDCs that lack trained medical personnel and refrigeration, this is a cheap and
effective mode to deliver medicine or vaccines.
4) Reduces environmental pollution
With the growing awareness on use of chemicals in agriculture and negative impact on the
environment, crops are genetically modified to reduce reliance on such chemicals.
For example,
o the use of GM food like Bt corn eliminate the need of application of chemical
pesticides hence reducing the worry of consumers which worry about the health
hazards of eating food treated with pesticides.
o it is not cost effective to manually remove weeds. GM foods can begenetically
engineered to be resistant to one powerful herbicide and this reduces the amount of
herbicides needed, reducing production cost and environmental damage.
Section III: Threats of GM food
1) Loss in biodiversity3
When predators consume the prey that has eaten GM crops, the gene bioaccumulates in
the body of the predator.
For example,
o Harmless insects like the Monarch butterflies are unintentionally affected by pest
resistant plants when they were exposed to it. In 1980s, corn was genetically
modified to express the Bt toxin to kill European corn borer. The toxin present in the
pollen of the corn killed the larvae of the Monarch butterflies when they feed on
milkweed plants dusted with pollen containing Bt gene. This affects animals up the
food chain by bioaccumulation as toxins accumulate in the predator from the prey.
3
Biodiversity refers to the great variety of living things in an ecosystem.

6. 2) Loss of natural species
When pollen of a pest-resistant crop is carried by wind or insects to compatible natural crops
nearby, the offspring of the organic crops also become pest-resistant.
Such gene pollution is irreversible and results in the loss of natural plant species.
It may even result in the formation of superweeds which are resistant to most herbicides.
For example,
o a herbicide-resistant strain of the weed, Charlock, was discovered in the UK and was
found to have been genetically polluted by the herbicide-resistant GM rapeseed plant.
3) Potential health risks
Some risks associated with GM food includes fear that GM food might contain food
substances that people are allergic to (ie. allergens).
This is particularly so because GM food is not labeled, thus preventing consumers from
making an informed decision.
Allergenicity occurs when a plant creates a new allergen when introduced to a gene and the
plant is consumed by a person who is allergic to the allergens.
For example,
o scientists have used lectin – a protein found in beans – in potatoes to prevent aphids
from attacking potato plants. However, some people are allergic to lecting and may
unwittingly consume it while eating potatoes.
Also, in 2005, a GM pea project was abandoned after research mice faced health problems.
As such, the European Union (EU) has banned the import and cultivation of most GM food
crops.
Some countries facing food shortages (eg. Zambia) have also rejected GM food imports.
4) Economic concerns
Bringing GM food to market is lengthy and costly and agri-biotech companies wish to ensure
a profitable return on their business.
Hence many technologies and GM plants have been patented.
This raises the price of seeds so high that small farmers in LDCs cannot afford them.
As such, only rich farmers can afford to buy them, grow them and earn more profit. This
leads to a widening income gap between the rich and the poor.
This also led to the creation of large companies controlling GM food production and supply
(ie. agri-businesses)

7. Secondary 4 Pure Geography
Human Geography (2235/2)
Sec 4 Chapter 14
Will food shortages ever end?
Section I: Past successes
1) Reducing starvation and malnutrition
Advances in food production have led to an increase in food available for the world.
These can help reduce problems of starvation and malnutrition as food can provided to meet
nutritional needs of more than 800 million hungry people in the world. UN estimates that
there is more than enough food to adequately feed each person in the world.
Section II: Future challenges
1) Dominance of agri-businesses
Farming is increasingly being dominated by agri-businesses which are mostly found in DCs.
Many poor farmers especially in LDCs are unable to afford modern farming technologies
hence they are unable to compete with the agri-businesses.
In addition, since agri-businesses produce a large number of food crops, the prices of the
food crops have fallen.
For example,
o according to the ID21 research organisation, when coffee production increased by 61%
from 1960 to 2000, the prices of coffee fell by 57% in that period. This causes coffee
growers in LDCs to suffer losses.
2) Over-exporting food
Owners may choose to export food crops for profit-making opportunities instead of selling it
to their own people who will pay less than the importers.
For example,
o while the Punjab region grows an abundant supply of food and is known as the
‘granary of india’, most of its output is sold to Europe to be processed into cat and
dog food. Poor locals cannot buy food despite the large supply.
3) Lack of health education
Some people may suffer from malnutrition even if food is affordable and available because
citizens may not be informed of the importance of eating food from all nutrient groups.
This leads to them eating an insufficient amount and ultimately leading to suffer malnutrition.