Monocropping: Necessity Or Environmentally Neglectful?
I have been thinking about the environmental impact of food and drink for a while now; indeed it was one of my green New Year’s resolutions to eat a lower impact diet and I started by switching to one of the available cow’s milk alternatives (I eventually chose oat milk).
The problem I face is that the more I research the ins and outs of agriculture and how it effects the environment, the more I realise how big a topic it is – you could even say that I have opened up a can of worms by looking into it (yes, pretty cringeworthy I know).
Not being one to shirk a challenge, I have decided to gradually write a series of posts on the environmental impacts of agriculture and this is going to be the first; the subject matter is monocropping.
What is monocropping?
In all likelihood, you have seen the practice of monocropping on many occasions as it can be seen all across the UK countryside, visible from motorways and country lanes alike and for the rambling enthusiasts.
Monocropping involves growing a single crop variety across large swathes of land and is the reason you can see huge yellow fields of oilseed rape in the summer and endless ears of corn swaying in the breeze ready to be harvested in the autumn.
Farmers choose this method of farming primarily to achieve economies of scale which they hope will reduce their costs and increase their margins, but in reality this way of growing crops has many detrimental effects on the environment.
The practice of monocropping grew to global prominence during the cold war. America, concerned that hungry third world countries could become a breeding ground for communism, started to export this form of farming to poorer nations in the 1950s. This helped them to massively improve their food yield and so feed starving populations in what was dubbed, somewhat ironically, the ‘Green Revolution’.
Monocropping fits the logic of capitalism in which the division of labour and subsequent specialisation allows economies to produce greater quantities of goods and services. On farms, a specialisation in a small number of crops allows greater total amounts of food to be produced. At least that is how the theory goes…
Biodiversity Buckles Under The Strain
The most obvious drawback to a monoculture approach to farming is the effect on the biodiversity of those areas being farmed.
It was once the case that the staple foodstuffs we now rely on to feed much of the world were relatively rare, only occurring naturally in certain parts of the world. As the human race has ballooned in size, so too has the production of the most common foods; indeed a study by David Tilman (‘Global environmental impacts of agricultural expansion: The need for sustainable and efficient practices‘) says that production of wheat, barely, rice and maize has risen at a rate far greater than the growth in population.
These four crops combined now cover 588 million hectares of land – this is almost 40% of all cropland (Tilman). What’s even more incredible is that three of the four (wheat, rice and maize) account for 60% of all the calories consumed by the human race (source: What is Agrobiodiversity – Food and Agriculture Organisation of the United Nations).
What this must mean is that fewer alternative crop varieties are now grown and harvested. The UN FAO confirms this, estimating that over the last hundred years, 75% of the world’s crop varieties have disappeared.
Bugs Also Bear The Brunt
It’s not only plant life that suffers when single crop farming takes place; since they make up the foundation of any ecosystem, a lack of variety in plants can have a huge impact on the number and types of insect and vertebrate species that populate an area. Ironically this can actually lead to a drop off in farming yields over time because such organisms are incredibly important to fertility of the land. Nature really is in balance and the disruption to this balance due to monocropping often reduces the innate ability of a thriving ecosystem to regenerate the soil and pollinate plants.
Indeed, a study by Mark Winston and Lora Morandin found that canola farmers in Canada where able to increase yields by leaving some land fallow because this space became a haven for bees, which in turn accelerated pollination, leading to a bumper yield.
The situation is even more of an issue when you consider that much of the land being cleared for agricultural purposes is in regions with extremely high levels of biodiversity such as the Amazon rainforest. Approximatelty 13 million hectares of biodiversity-rich forest are lost each year in developing countries according to a 2008 study by Clive James (Global status of Commercialized biotech/GM Crops).
Rainforests alone provide a habitat for as many as 70% of the world’s animal species (excluding the ocean).
Fewer Predators = Pests On The Rampage
Monocropping also has the effect of reducing the number of predators (both birds and predatory insects) in an area of farmland; this can cause pest populations to get out of control. To combat this, farmers have had to resort to pesticides to protect their crops and in the US alone, the rise of intensive farming methods has contributed to a 10-fold increase in the use of pesticides over the last 40 years (Modern Agriculture: Its Effects on the Environment – Cornell University’s Department of Agronomy).
The use of pesticides actually exacerbates the lack of biodiversity because they are indiscriminate in their effect, not only killing the pests but also other organisms that may actually be beneficial to crop yields either because they are a natural predator to the pests or because they assist the crop in some other way.
I’ll cover pesticides more thoroughly in a subsequent post in this series.
Falling Back On Fertilizers
Along with the aforementioned reliance on pesticides when growing monocultures, farmers are increasingly dependent on fertilizers to maintain crop yields. This is because when land is use for continuous, intensive farming of a single crop, it takes its toll on the soil at a much faster rate than traditional fallow field farming and crop rotation which allow the earth to recover.
According to farming researcher John Jeavons, monocropping depletes the nutrients in soil 18 times faster than they can be replaced by natural fertilizers. A massive amount chemical fertilizer is thus needed to sustain this practice and lots of water is also required with around 70% of all human water usage attributed to agriculture.
The use of fertilizers has, in many instances, replaced the more environmentally friendly practice of planting cover crops which have been used since ancient times to improve the quality of the soil (leading to them being nicknamed ‘green manure’). For example, many types of legumes give a great deal of nitrogen back to the soil but chemical nitrates are now more favoured because they are easier to implement on one huge, single crop field.
Our Soil Is Slipping Away
Cover crops do not only give nutrients back to the soil, but they are also vital in protecting the earth from erosion. Thanks in part to their diminished use in the face of monocropping, soil erosion now takes place at an accelerated pace. In the US, for instance, around 10 times as much soil is lost to erosion than can be replaced through natural formation. Given that top soil can take as long as 300 years to form, this loss is effectively irreversible (Cornell).
Eroded soil can clog streams, disrupt aquatic ecosystems and compromise the drinking quality of water.
A vicious cycle caused by monocropping occurs when soil erosion leads to increased use of fertilizers. This is because the subsoil is less fertile than the top soil and is less well suited to retaining the fertilizer being spread on it. Both fertilizer and pesticides are more prone to run off into surrounding areas when applied to subsoil.
Other Reasons Monocropping Is Problematic
Monoculture farming is so prevalent that in many cases the desire to grow one of a handful of crops precedes the suitability of the local conditions to grow said crop. The demand for grains such as wheat, rice and maize means that they are obvious choices for farmers. The lack of other huge, liquid marketplaces means that growing alternative crops is a risky business because, as a farmer, you can’t be certain whether anyone will buy it when you have grown it.
And so, where the local soil is not entirely suited to grow these in demand crops, more fertilizer is required to generate sufficient yields.
- Monocropping can of course pose risks in of itself. The lack of biodiversity across farmland can lead to greater risk of epidemic since the close proximity of plants and the size of plantations encourages diseases to spread quickly.
- Monocropping is a case of putting all your eggs in one basket and this doesn’t only apply to farmers but to entire industries. In 2010, the droughts and rice eating pests in Vietnam lowered production greatly; rice exports fell by 24.9% in January and February and in a country where agriculture provides employment for 23 million people (and over 21% of GDP) this led to very difficult times for many.
- Focusing on just a handful of crops not only puts a country’s export market at risk as in the Vietnam case, it also increases their dependency on importing other foodstuffs that they themselves do not produce. This can put it at the mercy of the world markets and give it less food security should prices move against them.
- With whole countries dedicating much of their economic activity to growing certain crops and importing others, it means that food is shipped all over the world on a more regular basis than if each country produced more of it’s own food itself. I’ll write considerably more on food miles in a later post.
Stop The Monocrops?
The subject of monocropping has very few environmental positives to highlight but in reality it is the most efficient way right now to cope with world demand for food. There are projections that suggest this demand could double by 2050 and at this point so I don’t expect farms to suddenly shrink down again or to stop using fertilizers and pesticides.
There are however, many studies going on around the world right now to try and reduce the negative effects of monocropping and I will highlight some of these in a later post which is going to deal with solutions to some of the problems posed by agriculture.
Unfortunately monocropping is just the first of several major problems caused by the human race’s insatiable growth and appetite, there are other equally concerning dilemmas that present themselves but they will have to wait for another day.
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