Sustainability : Food

Sustainability : Food - Key SQA Definitions:

Global Food vs Population

As discussed previously, the global Human population has increased massively in recent times. This has put huge pressure on food production in order to sustain this increased population. At present, the Earth does have enough food resources to sustain the Human population, but these resources are not evenly distributed and people across the planet do not have equal access to it.

There is also a significant difference between access to food and access to suitable nutrition. 

As of 2019, 633 Million people (8.9% of global population) are classed as being undernourished (they do not have access to the minimum amount of the nutrients or foods essential for health and growth), with 45% of childhood deaths worldwide being caused by hunger and hunger related causes. 

However, this undernourished group is not spread evenly around the globe, but are concentrated in certain regions :- 

Also, the number of people globally who are classed as undernourished is currently on the rise, with 118 million more people classed as undernourished in 2020 than in 2019 :-

What causes undernourishment? 

The top four causes of undernourishment globally are :- 

1. Poverty 

2. Food Shortages (Seasonal Hunger)

3. War and Conflict 

4. Climate Change


Nearly half of the world's population currently lives in poverty, which is defined as an income of less than US $2 per day, including one billion children. Of those living in poverty, over 800 million people live in extreme poverty, surviving on less than US $1.25 a day.

Undernourishment and Poverty are well correlated with each other, this means that high levels of poverty are a good indicator of high levels of undernourishment globally :-

Seasonal Hunger

Seasonal hunger is a repetitive cycle of predictable undernourishment that occurs between harvest seasons, when the previous year’s food stocks are running low or have run out, food prices are high, and income is scarce. 

The graph below shows how the percentage of households in Malawi who are food insecure vary across a year (based on data from 1982-2012) :-

Conflict and War

Conflict and Wars have devastating impacts on food systems, as they negatively affect almost every aspect of a food system, from production, harvesting, processing, and transport to input supply, financing, marketing, and consumption. 

As with Poverty, regions experiencing high levels of Conflict are a good indicator of high levels of undernourishment :-

Climate Change

Too little - or too much - rainfall can destroy harvests or reduce the amount of animal pasture available. These fluctuations are made worse by changes to established weather systems for example El Niño and the Monsoon. 

Extreme climate patterns also tend to affect the poorest regions of the world the most. The World Bank estimates that climate change has the power to push more than 100 million people into poverty over the next decade.

Strategies in farming for a secure food supply

In order to ensure that the food supply can be met, different techniques can be used to boost production, for example:-

Intensive Farming

Intensive farming simply means farming practices that maximise the food yield obtained from livestock and crop plants. 

Two examples of this are Monoculture production and Battery farming:-

Monoculture production

Monoculture production involves only one high yielding species of crop being grown. It is usually (but not always) grown using lots of fertiliser. However, if this particular species is susceptible to a disease that reaches the area, then the entire food crop will be destroyed. If forests are cleared for Monoculture production, a huge loss of biodiversity can occur. 

Battery farming

In Battery farming, livestock (such as chickens) are held in small cages to make them easier to manage, and allows more animals to be kept in a given space. Animals kept in these conditions however, have a higher risk of developing stress and disease which may affect produce quality. 

Farm Worker/Manager

You would do practical and manual work on a farm. You could look after animals like cows, chickens or pigs or grow and harvest crops. You’d operate farm machinery and do general repairs. You’d need to develop technical knowledge for using the machinery and have an awareness of health and safety. You could work on any of the three main types of farm; livestock, arable or mixed farming. 

You could progress to a farm manager where you would run a farm as a business, so you’d plan which crops or livestock would be the most profitable. You’d manage the farm workers, control the budget, and buy and sell the farm produce. 

You’d also be expected to find and develop new activities to keep the farm profitable. So you could also have responsibility for other activities where the business has diversified. For example there may be a farm shop, horse riding facilities or accommodation for tourists. You may also be responsible for mitigating greenhouse gas emissions from farming processes, as well as helping the farm adapt to potential effects from climate change.

Farm Worker

Farm Manager

A Career as a Farm Worker or Manager

Salary : £18,000 - £38,000

Farming Working Hours : Your working hours would vary depending on the time of year. At busy times you are likely to work long hours, with early morning, evening and weekend work.

Typical Entry Requirements : There are no set qualifications required to become a farm worker,but it helps to have an interest in farming and working outdoors. You may be able to train through a Modern Apprenticeship. This combines on-the-job and off-the-job training leading to relevant Scottish Vocational Qualifications (SVQs). 

 Most farm managers also have a qualification in agriculture. Qualifications that build knowledge of legislation and regulations relevant to farming are of particular value. Courses and qualifications are available through agricultural colleges and universities. They include HNDs and degrees

Skills Required : 

Agrochemicals (fertilisers and pesticides)

The use of agrochemicals (chemicals such as fertilisers and pesticides) are used to boost plant production in farms globally. They can come from natural sources (see Organic Farming below) but usually are artificial chemicals that are either added to the soil or sprayed directly onto the plants.


Fertilisers are chemicals that have been added to the soil to replace essential nutrients lost due to previous farming. The key chemicals required for plant growth are Nitrogen (for leaf and stem growth), Phosphorous (for root development) and Potassium (for fruit development and disease resistance). 

Fertilisers, however, can run off of fields and into rivers causing eutrophication (when the nutrients cause a population explosion of photosynthetic organisms in a waterway).


Pesticides kill organisms that would otherwise compete for crop plants for nutrients or eat the plants themselves.  However, these pesticides can kill non target species (such as Bees) or cause bioaccumulation in the food web.

Genetically Modified (GM) crops

Scientists can alter the characteristics of crops by inserting a gene coding for a desired characteristic. This can include disease resistance, higher yield or even those coding for a richer, better taste. 

However, many people will not eat GM crops as they worry that it will harm their health (No peer-reviewed scientific study has shown any risk) and many conservationists worry that GM crops will crossbreed with native species to produce hybrids.

Organic Farming Practices

Organic farming uses natural methods to grow food. No artificial chemical fertilisers or pesticides can be used if a farm wishes their products to be labelled organic. Organic farming is considered to be environmentally sustainable as it aims to minimise damage to ecosystems.

In order to still remain productive, organic farming uses organic fertilisers and natural pest predators instead of artificial chemicals:-

Organic Fertilisers

In order to gain bigger yields from depleted soil, farmers will use organic fertilisers such as manure or animal slurry to provide the essential nutrients for plant growth. 

Natural Predators

There are many predatory insects that live in agricultural fields, actively hunting down pests such as aphids, pollen beetles and slugs.

These include well-known predators such as ladybirds, ground beetles, and wolf spiders and also lesser-known species such as lacewings, parasitic wasps and hoverfly larvae, and supporting these insects can reduce the impact of pests in organic farming. 

There are disadvantages to organic farming, however. Yields from organic crops are usually lower than those from inorganic crops (as high yield providing chemical fertilisers are not being used). Also, organic farming is more labour intensive (more work is required to grow the same volume of food as other methods). 

Due to these factors, organically farmed produce is more expensive to buy than food produced by other methods. 

The video below shows a Ted-Ed discussion on how we can improve farming methods even further:-

Fishing and Aquaculture

Fishing is the hunting of aquatic organisms (fish, shellfish etc.) in coastal areas and the deep sea using a range of methods, usually involving nets or cages.

Aquaculture is the farming of aquatic organisms (fish, shellfish etc.) in both coastal and inland areas, using methods to boost production to levels higher than could be found in the natural environment. 

Fishing in Scotland

Marine Scotland (part of the Scottish Government) is responsible for controlling the activities of all fishing vessels operating within the Scottish zone, as defined by the Fishery Limits Act 1976 and the Scotland Act 1998.

This covers the North Sea and west of Scotland out to 200 nautical miles. It is also responsible for managing and controlling the activities of all Scottish vessels wherever they may fish, including how much of each type of fish they may land (known as a fishing quota). 

Seafood is Scotland’s second largest export and was worth approximately £560 million in 2021:- 

Types of Fishing in Scotland

There are three main types of fishing used in Scotland for Oceanic fishing:-

Pelagic Trawling

This type of trawling involves dragging a net through the middle of the water column to catch fish that feed there. In waters around Scotland, this is most likely to be mackerel and herring. 

As pelagic trawls do not make contact with the seabed this type of commercial fishing does not cause as much damage to the marine environment as seabed trawling. However, there can be issues with high levels of bycatch of non-target species.

Bottom Trawling

This is a type of trawling involves nets being dragged across the seabed to catch the species of fish which live and feed there. In waters around Scotland, this is likely to be cod, haddock, whiting and similar species.

As these type of trawl nets are in constant contact with the seabed they cause damage to the marine environment with seaweed beds, corals and other features which provide a habitat for marine creatures likely to be destroyed by seabed trawls.

Purse Seine

Purse seining works by drawing a vast net around a school of fish. The net is then pursed (drawn closed at the bottom) trapping the fish inside and the net can then be pulled onto the vessel. This method is used to catch pelagic fish that are found in a shoal or school such as herring, mackerel, sardines and many species of tuna.

 Small-scale purse seining can be relatively low-impact as the seabed is not damaged, however, large-scale purse seining can be highly damaging to fish stocks due to the large numbers of fish which can be caught.

And there are two main types of fishing used in Scotland for Shellfish:-


Dredging is used to take shellfish such as oysters, mussels and scallops from the sea. Dredgers tow metal cages across shellfish beds. Metal beams or teeth are used to scrape the shellfish free from the seabed when they then fall back into the cage or into a net or bag attached to the cage. 

Dredging is one of the most destructive methods of commercial fishing as it tears through shellfish beds and causes severe damage to the seabed and non-target species.

Pots, Traps & Creels

Lobster and crab pots, traps or creels are cages made out of metal, wood, rope or a combination of different materials. They are baited with dead fish and lowered to the seabed on ropes and a buoy is used to mark the location. Their design allows crabs and lobsters to enter the pot and become trapped inside, with the fishermen returning to empty the pot after a day or two. 

This is a low-impact form of commercial fishing as there is little to no bycatch and immature and berried (egg carrying) crabs and lobsters can be returned to the sea unharmed.

Sustainable Fishing in Scotland

In order for fishing to be sustainable, fish species must be given enough time to reproduce and replenish their numbers. 

Sustainable fishing methods include:-

Promotion of Alternative Species 

In order to reduce the impact of overfishing on specific high use fish, the Marine Conservation Society publishes an annual 'Good Fish Guide', allowing consumers to make informed choices when buying fish : 

Fishing Quotas & Seasons

Overfishing occurs when fish stocks are reduced to below acceptable levels. 

The results of this not only affect global food security, but marine ecosystems and the social and economic well-being of the coastal communities who depend on this activity for their livelihood. 

By setting Fishing Quotas on the maximum amount of fish that can be landed, fishing (in theory at least) can be kept at a sustainable level. Quotas do this by ensuring a large enough wild population to replenish the numbers that have been removed by fishing. 

Fishing Seasons help keep fishing at a sustainable level in a similar way. In Scotland, Salmon can only be legally caught in rivers between the 11th of February and the 31st of October. This is because Salmon spawn (reproduce) over the winter months. By preventing fishing during this time, the Salmon can reproduce without interference and stress, resulting in higher numbers of healthy fish.

Examples of historical overfishing include:-

Whaling in the 19th & early 20th Century

People have been whaling for thousands of years. The Inuit (who hunted in the Arctic Ocean), Basque (who hunted in the Atlantic), and Japanese (who hunted in the Pacific) relied on whales to provide material goods, as well as part of their cultural identity.

In traditional whaling cultures, every part of the whale was used. Meat, skin, blubber, and organs were eaten as an important source of protein, fats, vitamins, and minerals. Baleen was woven into baskets and used as fishing line. Bones were used primarily for toolmaking and carving ceremonial items such as masks.

From the 16th to 20th century, Whale oil and baleen (sometimes called whalebone, although it’s not bone at all) were valuable commodities. 

Whaling in the United States hit its peak in the mid-1800s. New technologies, including gun-loaded harpoons and steamships, made whalers around the world more efficient. The American whaling fleet, based on the East Coast, operated hundreds of ships in the South Atlantic, Pacific, and Indian Oceans. Whaling was a multi-million dollar industry. 

The global collapse in whale numbers led to the collapse of the industry and the global banning of commerical  whaling since 1986, however some countries continue to do so in a limited capacity.

Northern Atlantic Cod (1990s)

The Grand Banks of Newfoundland are a series of underwater plateaus found off the northeast coast of Canada. For centuries the Grand Banks produced a seemingly endless supply of cod and other commercially valuable fish. 

However, overfishing and mismanagement of stocks in the second half of the 20th century saw the number of cod shrink and then ultimately collapse, leading to a moratorium on fishing for Cod in the Grand Banks in 1992.

This moratorium (the total ban on commercial fishing for cod), devastated the local economy and caused significant social issues for the people of Newfoundland, with 37,000 people losing their livelihoods. 

Studies of the Northern Atlantic Cod have show since that the moratorium came too late, and Cod in large numbers may never return to the Grand Banks. 

The graph below shows the amount of Cod landed in Newfoundland since the 1960's:-

The population crash of Cod in the late 1970's can clearly be seen, as well as the impact of the moratorium in 1992. In recent year, some limited fishing has been allowed again, but at severly reduced numbers.


Wherever there is fishing, there is bycatch - the accidental capture of non-target species such as dolphins, turtles and seabirds. Modern fishing gear, often undetectable by sight and extremely strong, is very efficient at catching the desired fish species as well as anything else in its path. This bycatch is hauled up with the main catch, and then discarded overboard. These unintentionally caught animals often suffer injuries or die.

Marine Protected Areas & Zoning

The Marine Protected Area (MPA) network involves 231 sites covering 22% of Scotland’s marine environment. MPAs are areas where potentially destructive human activities are regulated to protect natural and cultural features. MPAs can also be beneficial to fisheries, creating safe havens for commercial species to reproduce, often followed by a spill over into surrounding areas.

Zoning aims to protect wildlife and to reduce conflict of activities by designating what activities can occur in which locations. People carrying out activities not permitted in a particular zone will be fined, for example a zone may permit Creel fishing but prohibit Dredging. This controls the use of the locations to reduce overall damage to fish stocks and ecosystems. 

The map below shows how the waters around Scotland are zoned. Fishing is either restricted or banned in all coloured areas:-

To find further information on the purpose of each individual MPA, please follow this link

Zoning Case Study : Lamlash Bay No-Take Zone

Lamlash Bay No Take Zone (NTZ) is the first Community-led Marine Reserve of its kind in Scotland and was established in 2008 off the coast of the Isle of Arran, Ayrshire. Within the NTZ, no fish or shellfish can be taken from its waters or seabed, including the shore area.

It covers 2.67 sq km and was the result of 13 years of campaigning by the Community of Arran Seabed Trust (COAST).

Despite being such a small area, during the past 10 years researchers have found that the size, fertility and abundance of commercial species such as lobsters and scallops is significantly better within the No-Take Zone. Seabed biodiversity is also found to be increasing by 50% and anecdotal observations from divers, fishermen and anglers indicate that the seabed and fish are recovering. 

Note - for an article covering the progress of the Lamlash Bay No-Take Zone, please see - This Link 

Aquaculture : Traditional High Density Cages

Aquaculture is the farming of aquatic organisms in both coastal and inland areas involving interventions in the rearing process to enhance production. It is the fastest growing food-producing sector globally and now accounts for 50% of the world’s seafood.  In Scotland, Aquaculture contributes £1.8 billion to the economy and employs over 9,000 people directly, with many more in the supply chain. 

The video below shows an overview of Aquaculture, including come of the issues it can cause:-

Aquaculture in Scotland involves rearing finfish (for example Salmon or Trout) in both freshwater and the marine environment as well as Shellfish and Seaweed. 

Finfish are normally hatched and reared through the early stages of life in land-based hatcheries and then transported to freshwater or marine cage sites. These cages are normally 90-110 meters wide and 15-20 meters deep; holding the amount of water equivalent to approximately 20 swimming pools. Cages are anchored to the seabed using ropes, chains and heavy specialised anchors. Each cage will hold on average between 45,000-55,000 fish. 

Traditional methods of Aquaculture rely on large quantities of antibiotics and pesticides (to reduce parasites) as well as large quantities of feed fish, usually from wild caught sources. Artificial pigments can also be used to make the meat appear a more appetising colour. Other environmental concerns can be seen in the infographic below:- 

Sustainable Aquaculture : Integrated Multi-Trophic Aquaculture

Integrated Multi-Trophic Aquaculture  (IMTA) is a form of polyculture which mimics the nutrient flows in natural systems by using the waste from one part of system as input to another. In conventional salmon farming, around 60% of the nitrogen in the salmon feed is lost to the wider ecosystem and can have negative ecological impacts if present in high concentrations, on top of the waste matter from the fish themselves.

In IMTA, seaweed and shellfish are grown close to the fish cages in order to maximise uptake of the nutrients that would otherwise be lost. The shellfish benefit from the organic matter and the seaweed from the soluble nutrients, including nitrogen. 

These can then either be sold on for profit, or if the system is used a sustainably as possible, the shellfish can be used to produce feed for the fish, completing the cycle:-

Fish Farm Worker

You would breed and rear fish and shellfish, monitor their water conditions and harvest the stock for sale at market. You could grow fish such as salmon, trout and halibut for the food industry. Some fish farmers rear other types of fish to stock lakes and rivers for angling or for ornamental ponds. 

Fish farms are generally located in lochs and in the sea off the coast so you’d need to be able to swim. Many fish farms only have a few staff so managers often do many of the above tasks, as well as supervising fish farm workers. Some fish farms also provide facilities for anglers.

Fish Farming

The Life of a Fish Farmer

A Career as a Fish Farm Worker

Salary : £23,400

Fish Farming Working Hours : As fish farms operate seven days a week, your hours may include early mornings, evenings and weekends, perhaps on a rota system. You will normally be expected to work 5 days out of 7 and will be paid overtime for hours worked beyond that.

Typical Entry Requirements : Qualifications at SCQF level 4/5 are recommended to get into this role. Entry to the job can be competitive. Once in the job you can gain relevant Aquaculture or Maritime qualifications such as a Scottish Vocational Qualification in Aquaculture (SCQF level 5-7) or a Diploma in Maritime Studies (SCQF level 5). 

If you are interested in gaining additional qualifications, it is possible to study an HNC in Fish Farming (SCQF 7) or a Degree in Aquaculture (SCQF 10).

Skills Required : 

What is the environmental impact of your food?

Knowing the impact of your food choices is the first step into making an individual difference. There are several ways to quantify the effect of your choices on the environment:- 

Food Miles

Food miles are the distances that your food travels from where it is grown to where it is consumed. They are used as a measure of the environmental impact of food production, along with factors such as transportation and greenhouse gas emissions.

Nutella - 28,731 Miles

Nutella is one of the more internationally sourced foods. With the hazelnuts travelling over 2,260 miles from Turkey, the palm oil from Malaysia (6,485 miles) and the sugar and soya coming from Brazil (5,447 miles), it all adds up.

Snickers - 50,791 Miles

Easily one of the most well-travelled products, Snickers bars contain ingredients from all over the world. 

Some of these include: coconut oil from the Philippines (6,795 miles), peanuts from Argentina (7,291 miles) and vanilla extract from Mexico (5,454 miles). 

However, Snickers bars do contain some local ingredients too, with skimmed milk powder and egg white powder coming from the UK.

Big Mac - 8,050 Miles

For such a global icon, the average Big Mac in the UK is surprisingly local, at least compared to some of the other foods. This is due to McDonalds’ commitment to using local producers for their food items. 

As such, the buns come from Oxford (77.5 miles), the beef patties from Scunthorpe or Waterford, Ireland (270 miles on average), the lettuce from Chichester or Spain (557.4 miles on average – it’s seasonal), the cheese from Northern Ireland (509.2 miles) and the Big Mac sauce from Lancashire (222.6 miles).

Only the onions and pickles come from further afield: the onion from the US (4,484 miles)  and the pickles from Turkey (1,930 miles).

Carbon Footprint of your food

How far your food has travelled is not the only indicator of its environmental impact, however. The process of growing/rearing, farming, processing, storage and transport methods all affects how much carbon dioxide is emitted by your food across the supply chain. This is know as the Carbon Footprint (or Foodprint) of your food.

The diagram below shows some of the average amount of Greenhouse gases released globally per kg of product, including how this is split up across its supply chain:- 

Carbon Neutral & Offsetting

For a food to be considered 'Carbon Neutral', the carbon emissions throughout the life cycle of a product need to be calculated. This includes emissions caused by raw materials, production, distribution, processing and packaging of the product as well as what happens at the end of the products life. 

These emissions are then offset through certified carbon offset projects. Carbon offset projects are projects that contribute to the reduction of greenhouse gases.

For example, these might be afforestation or forest conservation projects that reduce the concentration of CO2 in the atmosphere by creating additional or preserving existing wooded areas or projects that support the transition to renewable energy or biomass. 

Carbon offsetting schemes can sometimes be criticised, however, as they could be seen as an excuse for companies not to work towards reducing their actual emissions; that it is better to reduce the emissions at source, rather than trying to clean them up afterwards.

The video below shows an overview of Carbon Offsetting:-

Reducing the environmental impact of your food : Alternative Choices

One of the key ways to reduce your food's Carbon Footprint is simply to make more informed choices. By knowing what types of food are high Carbon emitters, you can make choices that can reduce this impact. 

The table below has been produced by the Scottish Government in partnership with the Climate Challenge Fund to show changes that you can make to reduce the Carbon Footprint of your food:-

To find out how your personal food choices impact the environment, please click on the image below to access an interactive Food Impact calculator:-

Reducing the environmental impact of your food Case study : Milks

An example where there is a variety of choice of products is Milks. The UK has a strong plant milk market, valued at £266 million in 2019, accounting for approximately 15% of the total European market.

By 2025 the value looks to increase by more than double, reaching £585 million and growing at an estimated growth rate of 13.8% between the years 2020-2025. 

The graphs below show how the environmental impacts of Cow's Milk and Plant-based alternatives compare to each other:-