Food is quite simple stuff. We grow it or we catch it or gather it, we might cook it, and then we eat it. For many of us, food is more about the choices available. What to eat? When to eat? How to eat less? How to eat humanely? How to eat ethically? Are food kilometres important? Paleo? Neo? Vego? Vegan? Ovo-Lacto? Or, perhaps most importantly, which of these questions are important for us and the planet, and which are irrelevant?
First, let me answer your question about the quantity of food. It’s a good question, and the answer isn’t obvious. Is there enough food in the world? The answer is ‘yes’. In fact, so much food is produced that there’s enough to give every person on earth more than twice as many calories as they need. (Each day there are 5,600 calories of food grown per person, whereas adults only need 2,600 calories). Few people are aware of the considerable excess in the food supply. Welcome to an exclusive club of people who know that the world is overloaded with food.
Today, the population is 100% more than it was in the mid 1960s, when the food excess was small. There are three and a half billion extra people now. But over the same period, food energy production has increased by more than 200% (from 24,000 PJ/year to 60,000 PJ/year). Over the last 40 years,food production has increased at more than twice the rate of population increase. An amazing achievement, and has been achieved in most countries around the globe. Many poor countries have increased their food supply by more than the average.
Currently, there is no shortage of food on earth. In fact, the reverse is true; the food surplus is massive.
There’s heaps of food. So, why would I want to write this essay? I invite you to consider the following facts and figures concerning food production, and make up your own mind about the state of the global food supply.
Nobody should be starving, as explained above, but people are starving and people are undernourished – on every continent except Antarctica. In some regions, there are millions of people undernourished. Although we grow 100% more food than we need, about 15% of the population in poor countries don’t receive the food they need. Besides the diversion of food as part of warfare, there are some simple reasons why food does not reach the people who need it.
The map below shows the uneven distribution of food, based on the average daily calorie consumption by country (source: Wikipedia). Yellow is greater than 3000 calories per day (excess), while the dark grey colour is less than 2000 per day (insufficient for adults). Much of the world has either an excess or insufficient supply of calories. South America is the only continent without widespread excess or deficit. Of course, within many countries there are large regional and sociological differences.
Given that there are serious inequities, I want to know the reasons for such strong differences in the food supply. The obvious reason is the main reason – in poor countries food is too expensive to buy. The United Nations have a food price index that shows large increases in recent years (graph below). Conventional economic theory says that when a commodity is in excess supply, the price is very low. Especially if some of the commodity has low quality, in which case the price is expected to be very low. This hasn’t happened for food, because the economics of the food supply are subverted by wealthy consumers.
Food is now too expensive because food prices have been globalised. The prices have been maximised globally because food is sent to wealthy people if wealthy people will pay more for it. Whether they eat it or not. If the oil price goes up, corn can be cheaply converted to ethanol, and the corn will fuel a car instead of feeding hungry people. Undeniably, the “highest bidder eats” model has been the one that the world has increasingly adopted for several decades now. In recent years, the concept has expanded so that the highest bidder also gets the automotive fuel and oil, while the poor are undernourished. Unfortunately, governments around the world are opening up global markets rather than asking whether these open global markets cause harm to poor people.
Within countries there are also open markets working against a more equal distribution of food. With increasing urbanisation of traditionally agriculture-based populations in China, India and other countries, the connection between people and food growers has been getting weaker for several decades. More of the remaining farmers are growing and selling crops for cash rather than keeping crops for their own use. For some people, cash is more difficult to store for a bad season than food. The immediacy of cash puts farmers on a treadmill of producing bulk commodities instead of producing food for local consumption. The economics of food supplies are complex, and I don’t claim to be an expert, but long-distance transport of food, and the trend towards cash crops is having consequences for many people.
While mentioning food kilometres, there is a lot of conflicting information out there, and it seems difficult to work out whether it is a big problem. Here’s your answer. Although all emissions are a problem, food kilometres are only about 4% of greenhouse emissions from the food industries. A high proportion of that 4% occurs from market to home, because only a small amount of food is moved in a typical car trip from the market to home. This is by far the least efficient part of the journey, emitting up to 100 times as much per food kilometer as long-distance transport by truck. Sea transport has exceptionally low emissions per kilometer and per kilo – so the food kilometres in sea-transported bulk commodities (such as grain, coffee, tinned veges) have very low emissions. And, of course, purchasing food from low-income countries, via a FairTrade system, may have preferred ethical connotations than purchasing from other sources.
Perhaps the most baffling and worrying aspect of food supply is food waste. The photo below shows good, but imperfect, oranges in California being dumped into landfill (photo from the USDA). Nothing unusual here – it happens to usable food by the thousands of tonnes every day, and in most countries.
One third of food is wasted before it gets to the consumer. This is not a simply a problem of rich countries, where food choices concerning unnecessary standards and the demands of continuous access lead to waste. In India, with its hungry millions, about one third of food is wasted before reaching the consumer, according to a recent statement by India’s Minister for Agriculture and Food Manufacturing Industries.
Grains are some of the most nutritious foods available, and produced in vast amounts, so anything that affects grain production and use has a huge influence on food supply. Unfortunately, a great deal of waste occurs during grain harvest, preparation for storage, and storage. For example, if grains aren’t dry when stored, they are prone to moulds and mildews and quickly become inedible. http://en.wikipedia.org/wiki/Granary explains some of the details. Recently, in Vietnam, I saw many people using concrete and bitumen and gravel roads to dry rice. The warmth of the road and the wind from the traffic was helping, but it was lightly raining, and it seemed that the produce would go to waste. Simple driers such as dark-coloured tarpaulins (solar powered!) would help so much in these situations.
Photo of grain stores in West Java, courtesy of Wikipedia.
The misuse of human food
Another major issue is that one third of grain production is used to feed livestock. That’s one third of what isn’t wasted in harvest and storage. Basically, animals are fed grains that are energy dense, and therefore grows more meat per kg, and low in fibre, so animals can eat more kg of feed. This creates more fat, less sinew and more favourable flavours in the meat. This is unheathy for consumers, but it is what the food supply chain and many consumers are currently demanding.
Cows, goats, sheep and other herbivores used to be fed grass and clover and brush. Pigs and chickens were fed food scraps and some spoilt grain. Animal growth rates were slower. The meat might have been tougher, and the taste might have been stronger. The meat was from older animals that used their muscles for walking around to get food and water. Was it so bad? I don’t believe it was. Was it more efficient? In terms of the area used and time needed to produce meat, it IS inefficient. But in just about every other way that you can measure it, the grass and scrap-fed animal production systems are wonderfully efficient. Pastures grow from good soil, sun and rain. Food waste wasn’t wasted – and cmost of it is still valuable stock feed. That photo of Californian oranges? Mixed with a few other things, they could feed some very happy cows, chooks and pigs. Except for the chicken because they don’t have teeth. But they DO like an orange.
One of the main concerns over feeding food scaps to livestock is that diseases might be transferred around the food chain in a cycle, building to an epidemic in either the animals or in humans. However, some countries have legislated to allow food waste as a feed for livestock, choosing instead to treat feed or quarantine certain high risk feeds. Treatment of scraps, for example by pasteurization, may be sufficient to kill a wide range of pathogenic organisms. It works for humans who like milk.
The options needed for reducing the consumption of human food by animals are already available.
A feedlot in Texas for fattening beef cattle. Photo Courtesy of Wikipedia.
Waste by consumers like you and I is a large problem, not a little one. Many consumers purchase their food at irregular intervals, and rely on storage in refrigerators and cupboards. A trend in some countries towards fresh food over canned and frozen food has increased the difficulties for many people in maintaining food quality in the time between purchase and consumption. Commercial food manufacturers and sellers are famous for their wastage – especially those who rely on high quality ingredients and a very high standard of food aesthetics. Restaurants in particular. Every restaurant is a food waste nightmare. It has been estimated that food wastage from western restaurants ranges from one quarter to one half of the food purchased.
|Food loss and waste per person and year||Total||Production and retail||By consumers|
|Europe||280 kg||190 kg||90 kg|
|North America and Oceania||295 kg||185 kg||110 kg|
|Industrialized Asia||240 kg||160 kg||80 kg|
|sub-Saharan Africa||160 kg||155 kg||5 kg|
|North Africa, West and Central Asia||215 kg||180 kg||35 kg|
|South and Southeast Asia||125 kg||110 kg||15 kg|
|Latin America||225 kg||200 kg||25 kg|
Table courtesy of Wikipedia (http://en.wikipedia.org/wiki/Food_waste#Retail).
So that’s the story of producing, but then wasting food.
The environmental and ecological costs of food
The environmental cost of food production, distribution and consumption goes largely unnoticed. Why? I don’t know. Farming and grazing have been the main causes of plant and animal extinctions for a long time. Just in case you skimmed over it, and to make it clearer - Farming and grazing for the last few hundred years have been the largest causes of plant and animal extinctions in the last 64 million years on the Earth.
In this discussion of environment and ecology, I’m not focussing on genetic modification, or animal cruelty, or extreme examples of land contamination, or acute or chronic effects of pesticides on people. In my opinion, virtually 100% of the harm has been caused by the ‘normal’, uncomplicated farming of the land that has been going on for decades, using familiar technology, such as a tractor (or horses or a water buffalo), a plough (plow in the US), and something to harvest the crop. If you are wondering how growing a crop by ploughing the land and planting some seeds could destroy land and water and drive species to extinction, I have a whole lot of news for you.
Conventional tillage in preparation for planting (source: Wikipedia). Note the lack of forest cover in general, and minimal plant and animal biodiversity in the cultivated field. The purpose of ploughing is to kill all plant life.
I’ll start the next bit with a story. A BIG story. From space, astronauts can only see really big things. The Sahara desert. The Great Barrier Reef. The River Nile. But astronauts can see the rabbit proof fence. Not the fence itself, but the difference between the land on each side of the fence. If you’re not from Australia, you probably haven’t heard of the fence, despite the fact it’s easily the biggest fence in the world. It was built in the middle of Australia to stop rabbits spreading from the east to the west. Rabbits were grazing out land and reaching plague proportions in the south-east. To protect the southwest, a fence was built and maintained, and it kept out the rabbits. Free from the destruction of rabbits, farmers brought in more grazing animals, and in some places cultivated right up to the western side of the fence. The sheep and cattle grew fat, and many bags were filled with wheat.
Photo of the rabbit-proof fence. It is the longest fence in the world.
From space, astronauts report big differences between the eastern (rabbit ridden) side of the fence and the western side (grazed). The western side is brown and bare. In some places there are saline seeps where there were none before. Fencing the pastoralists and agriculturists out of the east side of the fence has protected the environment on the eastern side of the fence.
In Eastern Australia, in New South Wales, the Soil Conservation Service estimate that 25% of previously farmed land is now unusable. That’s a few million hectares of damage. How much land has gone from productive cropping land to uncropable in Australia? More land than is is presently cropped in England. We’ve lost more than England has. Worldwide, this is a huge problem. Farming is by far the greatest cause of land degradation and future losses of food production.
Global, regional and local environments are affected by agriculture and food production. Many of the problems arise from the simple fact that increased plant and animal production comes mainly from land clearing, the conversion of pasture land to cropping land, and increased intensity of operations on farms. These three things share something besides producing extra food. They produce serious amounts of pollution. In the discussion below, I’ll concentrate only on the few problems that are in my area of expertise (as a scientist).
1. When pasture and forests are cleared for farming, much of their stored carbon is converted to carbondioxide, and contributes to greenhouse warming and ocean acidification. Farming usually begins on fertile soils, covered in forest or woodland (trees and grass), which is cleared and cropped. In some cases the organic matter in the vegetation is burnt, with a dramatic release of thousands of tonnes of carbondioxide per square kilometre. However, the end result is generally the same as for burning when the soil is cultivated and cropped. The carbon is still converted to carbondioxide, but the process involved is microbial respiration instead of fire, and takes months or a few years instead of hours or days in the case of a fire.
After just a few years, regardless of the farming system adopted, a large proportion of the carbon stored in the natural environment will be released into the atmosphere as carbondioxide and act as a greenhouse warming gas. Per square kilometre, typically they will be 1,000 tonnes of carbon converted to 3,700 tonnes of carbon dioxide (based on 1% soil carbon). A typical Australian car emits just 14 tonnes of carbondioxide per year, so this small area emits as much as 260 cars. It a forest was cleared before cultivation, there would be an extra 100 to 500 car-equivalents of carbondioxide released per square kilometre (depending on whether it was a woodland or rainforest that was destroyed).
In Australia, we sometimes hear about the potential for soils to store carbon, and paying farmers for the carbon storage they can achieve. This has been true, to some extent, in southern Australia, and in the past. This is because many of the sandy soils were very low in organic matter, and with fertiliser and farming, the organic matter content increased. However, in many cases there was a large carbon store in the vegetation before it was cleared, so the net storage isn’t much, if anything at all. Many years of research show that only pastures can return significant amounts of carbon to farmed soils. And only forests can return carbon to pastures. Messing about with different crop, pasture and tree species is inconsequential.
It’s a fact that cropping releases very large amounts of greenhouse gasses to the atmosphere.
2. Conversion of forests and pastures to crops destroys biodiversity. Forests are valuable as habitat to a vast array of animals. But pastures, too have some diversity, and are important for many plants and animals. It’s not often that I’ve gone into a permanent pasture and not seen dozens of different plant species. Often, there will be fifty, and sometimes a hundred species in one field. In a crop, it is common to find just the crop and a fhalf dozen weed species. These don’t provide very much habitat for the animal community, other than some ants and moths and the like. There just isn’t the complexity of plant height, shape, food type or other attributes that would support a range of birds, amphibians, reptiles and mammals like forests.
This graph shows how even a simple pasture is a mix of many species.
Graph courtesy of http://www.evergraze.com.au
It’s a fact that cropping reduces biodiversity.
3. Conversion of land to cropping causes soil erosion. Sometimes the extra erosion is just 10 or 20% more than before, especially if the land was overgrazed pasture. But often there is 100% or 200% or 500% more erosion when land is cropped. Erosion depletes the land of productive soil, it is an expensive problem if the soil is deposited on roads or in drains or in houses, and it eventually winds up in rivers and oceans, where it causes severe environmental problems.
On steep land or in tropical areas, farming may increase the rate of soil erosion from 100 tonnes a year per square kilometre, to TEN THOUSAND tonnes of soil per year for every square kilometre. In some farming systems the rates of soil erosion are much higher than this. Is that affordable or sustainable? No. In many areas of the world, soils are running down faster than the world is running of of fossil fuels. You might want to read that again. We are losing soils fast. How fast?
Where I live, a hectare of farm can produce 5,000 loaves of bread. The soil erosion per crop is 10,000 kg, which is considered a good, low level by almost everyone (not me). That’s 2 kg of soil erosion for every loaf of bread, and 1000 times faster than the rate of soil development.
It’s a fact that cropping causes severe and damaging soil erosion.
4. Plant nutrients are good when they are in the soil feeding crops, but the same nutrients cause environmental damage in waterways, estuaries and the ocean. Coral reefs only occur in clear, low-nutrient water. It is no surprise then, that the Great Barrier Reef is affected by farming on the nearby mainland of Australia. The pre-European rate or soil erosion flowing to the reef was 3 million tonnes per year, but farming has increased that to 17 million tonnes per year.
One type of nutrient, phosphorus, is usually attached to soil particles, and travels with them to the ocean. The saltiness of the ocean then releases some of that phosphorus, and it fertilises algae in the water. Unfortunately, these algae are the enemy of sea grasses and corals. In many parts of the world, the marine ecosystems have become slimy and green due to excess growth of algae. A visit to an inland lake often shows the same effect.
It’s a fact that cropping pollutes the land, waterways and oceans with nutrients.
5. Converting forest and pasture to cropping land introduces a diverse and problematic range of herbicides, insecticides and fungicides.
Forests and pastures receive much fewer types, and much less quantity, and less environmentally damaging pesticides than cropping land. Tebuthiruron is an example of a chemical that has severe environmental consequences when it is used. It kills the forests to which it is applied. Because that destroys the habitat of a wide range of animals, it effectively kills them, too. The chemical is used in Northern Australia specifically to kill forest trees so that grazing and farming can go on. The simple fact is that dead forests and destroyed ecosystem are being exchanged for food.
There are many more cases of chemicals that last for long periods in the soil and waterways being used around the world. Atrazine is the most commonly used herbicide in the USA, and is very widely used in Australia (but banned in the EU). It persists in the environment and is readily transported. It is the subject of on-going debate about the levels that are harmful in the environment and harmful to human health (http://en.wikipedia.org/wiki/Atrazine). Atrazine is being used in close proximity to the Great Barrier Reef. In order to grow sugarcane. A completely unnecessary food. A food that is harmful to most of the people who consume it. Does this make sense? Harm the reef to make sugary drinks?
It’s a fact that large amounts of environmentally hazardous chemicals are used in cropping. The fate and environmental effects of many chemicals are not well known.
How to solve these things?
Food wastage must be treated seriously.
Food storage must be a higher priority for engineers, particularly in low income countries.
Converting pasture and forests to farms for grain production must stop.
Converting forests to pasture for animal production must stop.
Soil erosion must be reduced. The current rates are unsustainable in many of the cropping lands of the world. Soil erosion is a silent killer of future undernourished generations.
The source and fate of nutrients and pesticides must be better monitored and regulated.
Wealthy people must not be allowed to buy and waste food that is needed by undernourished people.
Poor people must not be encouraged to sell their household food supplies to rich people.
High income countries must help regulate the global food supply. An unregulated food supply isn’t working for people in low-income countries.
It’s food for thought.
All comments are welcome.