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2. Threats to resources

Agricultural land degradation

Between now and 2050, the global population will rise from 7.4 billion to more than 9 billion.33 The highest growth is likely to be in Africa south of the Sahara, the region currently worst affected by hunger; here the population will more or less double—at a time when agricultural resources are shrinking.34 Some 5 billion hectares are currently available for farming: 1.5 billion hectares of arable and permanent crops and 3.5 billion hectares of grassland and pasture.35

The opportunities to increase the amount of land available for agriculture are limited and any expansion is likely to be detrimental to forests and wetlands. Globally, 60% of forest clearance is done to create farmland.36 One-third of current farmland is already degraded—to a greater or lesser extent—by erosion, salination, compaction, acidification or pollution.37 Some 10 billion hectares of land are lost to erosion each year because of inappropriate land use—almost ten times the total agricultural land in Switzerland.38 New residential developments are gobbling up more and more agricultural land in developing countries. In both cases, it is often the best agricultural land that is lost.

Land grabbing

When it comes to soil, the battle for scarce resources has already begun. Rich oil states, emerging nations such as China and South Korea and increasingly private fund companies from the developed North are buying land in developing countries or leasing it on a long-term basis.

In October 2009 GRAIN, a non-governmental organisation specialising in this issue, listed a total of 140 hedge funds, private equity groups and financial organisations involved in this type of investment.39 Huge tracts of land are being turned over to monocultures for the production of food, animal feed and agro-fuels intended for export, including in countries where people are suffering from malnutrition. According to estimates by the World Bank, the Sudan leased or sold almost 4 million hectares of land to foreign investors between 2004 and 2009— roughly the total land area of Switzerland.40 The Land Matrix organisation keeps a record of all land sales and leasehold transactions and its data shows that the global figure currently exceeds 44 million hectares.41

Water shortages

About 20% of current arable fields are irrigated and 40% of all food is grown on irrigated land.42 The huge investment in irrigation systems since the 1950s has played a major role in increasing yields. By 1990, the total area under irrigation had almost tripled and currently 70% of the world’s fresh water consumption is used for agriculture.43

Water is an increasingly scarce resource in food production. A total of 1.6 billion people live in areas that suffer from water shortages.44 In many parts of Asia and Africa, the over-exploitation of water resources is now a problem in its own right, with groundwater levels dropping rapidly. Water shortages have also reached alarming proportions in the industrial grain-growing belt of the US Midwest.45

Loss of biodiversity

Similarly, the biological basis of food production is now much more fragile. Over the millennia, humans have used more than 10,000 plants as crops; today it is just 150 and the few plants still in use are becoming increasingly alike. A total of 12 varieties make up 80% of the plants used for food production.46

In the past, farmers have used plant propagation and livestock breeding to produce an enormous range of varieties suitable for use in an extremely wide range of conditions. Not only is the number of varieties shrinking but at the same time we are witnessing the triumphant global march of fewer but higher yielding varieties. For example, the potato is currently the fourth most important staple food and could play an even greater role in future in fighting global hunger. Potatoes were originally grown some 8000 years ago by the indigenous peoples of South America in the Peruvian/Bolivian Andes around Lake Titicaca at altitudes up to 4300 m. In addition to the wild varieties, there are more than 3000 cultivated varieties of potatoes.47 It is essential that they are protected because it is estimated that 75% of all varieties in the world are no longer cultivated.48

Similarly, the biological basis of livestock farming is shrinking just as fast. Since 1900, some 1000 livestock breeds have become extinct—including the Frutigen cow and sheep, the Freiburg cow and the Galloway pony.49 According to data from FAO, the UN Food and Agricultural Organisation, 1458 breeds, including the Brazilian Pantanerio cow and the Hungarian Mangalica pig, also called the woolly pig, are threatened with extinction; their loss would represent some 17% of all livestock breeds.50 This development is the result of indiscriminate crossbreeding, the use of non-native species, the decline of traditional forms of production and the neglect of species not deemed sufficiently productive. If the sole aim of agriculture is to maximise output, valuable characteristics are lost, e.g. an animal’s ability to withstand heat or cold or to make do with less water or lower quality feed.

Crops and livestock are but two of the factors in food security. In order to introduce new characteristics into crops, we need to make use of related wild varieties. This has been done, for example with millet, where a disease pathogen known as the barley yellow dwarf virus has caused enormous damage. The only way to fight the virus is prompt intervention with an insecticide that kills off the vector. That could soon change. Plant researchers have discovered a gene resistant to the virus in barley living in the wild (Hordeum bulbosum) and commonly found in the Mediterranean and Central Asia. This gene has been transferred to cultivated barley (Hordeum vulgare) by crossbreeding. The result is a new variety with a resistance to the pathogen.51

Hordeum bulbosum is a crop wild relative, or CWR. This is the specialist term used for wild plants that are sufficiently closely related to cultivated plants that their genes are interchangeable. This makes them potentially an excellent source for the breeding of new varieties.

There are more CWRs than you might think. Research has shown that the term can be applied to 83% of all flora in Switzerland and 143 varieties have already been placed on a priority CWR list because of their potential for use in cultivation.52

The world’s genetic reservoir is being eroded and between 10,000 and 25,000 animal and plant species die out each year.53 The process of evolution is such that some species will naturally disappear. However, the current rate of extinction is a thousand times faster than the natural rate.54 Agriculture—directly and indirectly (through deforestation)—is one of the main contributors to the biodiversity crisis.

A diverse animal kingdom is also an insurance against pests. Pests have natural adversaries, i.e. insects that predate or parasitize them. However, the decline in species affects both the beneficial insects and the pests; 35% of global food plants depend upon insects for pollination.55 More than 100,000 species have a role in increasing harvests. It is currently unclear whether they will be able to perform that function in future. Their populations are being weakened by habitat loss and reductions in crop diversity, as well as by pesticides-neonics in particular—both as topical sprays and as seed coating, mostly on genetically modified organisms (GMOs).

Pesticides in the environment

Recent studies have shown that 11–24% of pollen and 17–65% of nectar from fields sprayed with the insecticide neonicotinoid are contaminated with the poison.56 This group of insecticides represents a huge threat to the survival of pollinators.

A British study has produced similar findings. It compared data on the distribution of 62 species of wild bees with data on oilseed rape fields sprayed with neonicotinoids. Oilseed rape was chosen because it is attractive to bees. It was found that the pesticide caused significant damage to wild bee populations.57

Drift, run-off and leaching cause pesticides to migrate to other habitats and damage their biotic communities. An analysis of 838 studies from 73 countries showed that more than 50% of insecticide concentrations found in surface water exceeded the damage threshold for aquatic organisms.58

Between 2005 and 2012, the Swiss canton-based laboratories responsible for water pollution investigated more than 500 watercourses for traces of 203 active agents used as insecticides in agriculture. In 80% of cases, they found active agents and in 50% of cases there was at least one instance when levels exceeded 0.1 μg/l,the legal limit for water pollutants in Switzerland.59 It should also be remembered that the cumulative effect of pollutants below this level is not necessarily harmless.

Pesticides also pose a risk to agricultural workers. The World Health Organisation (WHO) estimates that between two and five million people are poisoned each year; 40,000 of these cases are fatal.60 The causes are often the use of highly poisonous substances long since banned in most industrial countries as well as the lack of the necessary protective clothing for farmers in developing countries.

Pesticides also affect consumers. Various studies have linked pesticide residues in food and the environment to chronic disease. In particular, pesticides are suspected of playing a role in the development of cancer, Alzheimer’s, birth defects, Parkinson’s and some development disorders.61

The Environmental Institute in Munich recently examined 14 types of beer available in Germany for the presence of glyphosates. Residues were found in every single case at levels of between 0.46 and 29.7 μg/litre;62 the limit for drinking water is 0.1 μg/litre.63 Glyphosate is suspected of being carcinogenic and those demanding a Europe-wide ban are becoming increasingly vocal. In October 2016, the Monsanto Tribunal in The Hague looked at the decade-long use of agrochemicals produced by the company and known to be harmful.64 It clearly demonstrated that their use has caused immense damage to human health and ecosystems. In addition, the manufacturing processes for agrochemicals (e.g. pesticides and fertilisers) and the monocultures required by their use are playing a significant role in climate change. The business models adopted by Monsanto and other corporations currently dictate global agricultural practices. The best way to promote and introduce agro-ecological methods on a global scale would be to deprive these corporations of the basis of those models. If food were produced in accordance with sustainable principles, we would eventually have no need to use contaminants. We know that they are highly suspect, but they are still produced in large quantities. This would not only avoid damage to the environment but would also benefit the world in other ways, e.g. in terms of health and climate change.

Greenhouse gases from agriculture

Intensive farming is also a driving force behind climate change. It is directly responsible for 13% of greenhouse gas emissions measured in CO₂ equivalents, i.e. methane from the stomachs and intestines of ruminants, nitrous oxide from too many fertilisers and CO₂ from fossil fuels used for energy. A further 18% is produced when forests are cleared to create new farmland.65 In the last 20 years, greenhouse gases from agriculture have increased annually by 1%, and by far the biggest contributor has been intensive livestock farming.66

In addition, the production of mineral fertilisers and agrochemicals as well as the use of agricultural machinery demand vast amounts of energy; this makes farming heavily reliant on fossil fuels. Producing a single food calorie can require up to 10 calories of external energy.67

In the final analysis, the ecological problems created by agriculture are the result of a reductionist approach to food production, where the sole aim is to produce as much as possible for as little as possible. However, food is only cheap for the consumer because the system outsources ecological costs, e.g. water pollution from pesticides, soil degradation, loss of biodiversity and the effect on climate change. It is we and our descendants who will end up paying those costs in some form or other.

In the meantime, the maximum yield policy is coming up against biological limits. In recent years, the increase in the yield per hectare from intensive farming has flattened out and between 1950 and 2001, the global rise in yields per year declined from 3% to 1%.68 In 24–39% of the areas that grow maize, rice, wheat and soya, yields per hectare have recently stagnated or even dropped.69 Plants cannot indefinitely increase their ability to absorb nutrients and convert them into vegetable material. We should also attach greater importance to quality and nutritional value and less on a process that simply increases the number of “empty” calories so familiar to us since the Green Revolution. It is also part of a new paradigm which was clearly advocated in the International Assessment of Agricultural Science and Technology for Development Report (IAASTD), published in 2008.

This report, compiled by 400 scientists from around the world over a period of four years, came to the clear conclusion that we could only nourish the world sustainably if we refocused our efforts and worked with nature rather than against it. The report, which was initiated by the World Bank and the United Nations, was signed by 58 nations. Unfortunately, however, its proposals have not been implemented.