Fossil Fuel On A Stalk
Crop agriculture is only viable on account of oil and gas. It is dependent on the production of vast amounts of fertiliser through the use of hydrocarbons, it relies on diesel for irrigation, machinery for harvesting, and oil for transport around the globe. Any discussion of greenhouse gases and sustainability in food production has to recognise this.
‘Fossil fuel on a stalk’ is a phrase taken from Lierre Keith’s ‘The Vegetarian Myth’ (p.107). She in turn draws on Richard Manning’s observation that, “it takes more than a calorie of fossil fuel to produce a calorie of food energy for humans – somewhere between four and ten calories of fossil fuel for a calorie of food” (p.108). The bulk of this fuel goes into the production of fertiliser for plant crops, with the second largest use being irrigation. The manufacture and use of farm machinery, essential to modern day mechanised farming techniques, is also dependent on fuel oil, as is the extensive processing, transport and distribution of food products in today’s globalised context.
The overwhelming majority of this energy use goes into the production of agricultural crops. Some of these are then supplied to animals in feedlot facilities, but this also is a result of the availability and subsidisation of fossil fuel-based farming, above all in the US (see here for more on this). A 2011 Paper produced by the UN’s Food and Agriculture Organisation (FAO) provides some insight into the issue (see here).
The Paper highlights the close connection between cereal production and crude oil with a graph showing how prices of the one track the other (p.iv). This interdependence is largely a result of two 20th century developments, the first being the invention of the Haber-Bosch process that allowed for the production of nitrogen-based fertiliser through an energy intensive chemical reaction. Some 5% of the world’s natural gas output (5 exajoules) is now devoted to this process (p.9). The second was the ‘Green Revolution’ of the 1960’s, which encouraged the use of plant varieties that could be combined well with chemical-based fertilisers and pesticides (p.3). One of the reasons for the current alarm around food production is a general recognition that the increased yields this generated were a one-off, and in any case are not sustainable going in to the future. This is not only due to the reliance on non-renewable energy sources, but also its effects on soil-depletion and water degradation (see here).
The Paper also supplies some interesting statistics on how energy is consumed in food production today. In the West, as little as 20% is actually involved in agriculture itself, the rest going on processing, transport, distribution, and preparation (p.10). This number alone sets discussion about greenhouse gas emissions in their proper context. When we look at livestock production specifically, including fisheries, the percentage drops to around 8% as against 11% for crops. In the West this figure is raised due to the practice of feeding grains to animals, something many of us are strongly opposed to, and by no means a necessary feature of pastoral farming (see here).
This stands in sharp contrast with the total dependence of crop agriculture on chemical energy. “Nitrogen fertilizer production alone accounts for about half of the fossil fuels used in primary production” (p.14). The use of chemically produced nitrogen in this way is itself a major source of pollution, both in terms of the atmosphere and run off, as its behaviour differs from the natural form of the gas (see here for a discussion of this). Once applied over a period of time, crop agriculture becomes totally reliant on the continued use of chemical fertilisers due to its effect of depleting the soil. In fact, it is not only the soil that becomes nutrient deficient, but the plants that grow on it (see here).
The problem is not confined to fertiliser. The use of fossil fuels has allowed for the expansion of arable farming way beyond those regions where water is supplied by rainfall. Some 40% of cereal production is now on irrigated land (p.14), where it is pumped and circulated from underground aquafers. Current rates of extraction exceed those at which the supply recharges, which means farmers have to go deeper and pump further (p.14). This is yet another reason why current crop agriculture is unsustainable in the long term.
When it comes to harvesting, some 27 million tractors are now in use (p.13). Their manufacture and operation make up a major element in the production of food, locating it firmly as an industrial process.
The bulk of this ‘food’ consists of items that are inedible as they stand. Richard Manning makes this point forcibly,
“America’s biggest crop, grain corn, is completely unpalatable. It is raw material for an industry that manufactures food substitutes. Likewise, you can’t eat unprocessed wheat. You certainly can’t eat hay. You can eat unprocessed soybeans, but mostly we don’t. These four crops cover 82 percent of American cropland. Agriculture in this country is not about food; it’s about commodities that require the outlay of still more energy to become food.”
“About two thirds of U.S. grain corn is labelled ‘processed’, meaning it is milled and otherwise refined for food or industrial uses. More than 45 percent of that becomes sugar, especially high-fructose corn sweeteners, the keystone ingredient in three quarters of all processed foods, especially soft drinks, the food of America’s poor and working classes.” (see here)
Food processing is therefore a further consumer of energy, the wet milling of maize alone making up 15% of the sector’s total input in the US. This product, as with other cereals, then needs to be dried before transport, another energy intensive activity. It will then hit the road. A typical daily shop for a household in the United States contains food that has travelled no less than 8,240km (p.17). In the case of fresh fruit shipped from New Zealand to Europe, this accounts for some 45% of the energy required for its production overall (p.17). According to the FAO paper, buying local alone would reduce greenhouse emissions by 4-5% (p.17), a significant enough figure that compares with the worst estimates for methane production from ruminants.
All of this allows us some perspective on the claims that eating meat is a major cause of climate change, and that switching over to plant based foods would be of benefit. A more serious program genuinely aimed at developing sustainable systems for food production would look instead at –
phasing out the use of chemical fertilisers altogether
tightly restricting access to deep water for irrigation
removing the need for heavy machinery in agricultural operations
switching to foods that do not require extensive processing
insisting on locally sourced items wherever possible
All of these items can be easily achieved through the adoption of ruminant-centred farming on grasslands, above all on land currently used for the cultivation of cereals. This should be a pivotal objective of any agricultural policy, using a range of tax measures and legislation. Here, environmental concerns overlap with health and nutrition. Initiatives could include –
a diabetes tax on grains and cereals to cover all the health care costs they generate
a 100% tariff on natural gas used in the production of fertiliser
a ban on water pumps beyond a certain capacity
subsidies for labour intensive forms of agriculture
warning labels and plain packaging rules for processed foods
customs duties on all products crossing state lines
At this point the political will does not exist to implement such a program, but that simply tells us what we need to do, the fight we have to wage. The industrial method of crop agriculture has been an absolute disaster for the environment, for native animals, for rural communities, for human health, it is time we went on the offensive to bring it to an end, before it brings us to an end.
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