Thirsty crops cause water shortages and pollution
Lack of sustainable agriculture: Biggest threat to the environment
Agriculture wastes 60% or 1,500 trillion litres, of the 2,500 trillion litres of water it uses each year - this is 70% of the world’s accessible water 1.
Many big food producing countries like the US, China, India, Pakistan, Australia and Spain have reached, or are close to reaching, their renewable water resource limits.
The lack of sustainable agriculture harms the environment by sucking rivers, lakes and underground water sources dry, increasing soil salinity and thereby destroying its quality, and by washing pollutants and pesticides into rivers that in turn destroy downstream ecosystems such as corals and breeding grounds for fish in coastal areas.
The main causes are:
- leaky irrigation systems;
- wasteful field application methods;
- pollution by agri-chemicals; and
- cultivation of thirsty crops not suited to the environment.
A WWF report, Thirsty Crops: Agricultural Water Use and River Basin Conservation, identifies cotton, rice, sugar cane and wheat as the 'thirstiest' crops in 9 large river basins rich in biodiversity. Together, these 4 crops account for 58% of the world's irrigated farmland.
- Thirsty Crops report: Agricultural Water Use and River Basin Conservation [pdf, 1.69 MB]
- Thirsty Crops booklet [pdf, 947 KB]
- Bottled water: Understanding a Social Phenomenon [pdf, 120 KB]
- WWF Report: Drought in the Mediterranean [pdf, 1.51 MB]
In Latin America, Africa and Asia, cotton is one of the most important cash crops for small farmers.
Although only 2.4% of the world's cropland is planted with cotton, it accounts for 24% of the world’s insecticide market and 11% of sale of global pesticides. 73% of global cotton harvest comes from areas under irrigation.
Diversion of water and its pollution by cotton growing has had severe impacts on major ecosystems such as the Aral Sea in Central Asia, the Indus Delta in Pakistan and the Murray Darling River in Australia.
More on the impact of cotton on freshwater >>
Although much of this habitat and species loss is historic, sugar production today - whether from cane or beet - has a wide range of negative impacts on soil, water and air. The Great Barrier Reef off Australia's coast, which suffers from effluents and sediment from sugar farms, is one of the best known examples.
Perverse subsidies and market barriers enable EU and US farmers to grow sugar cheaply and to dump it on the world market, with consequent economic, social and environmental impacts in developing countries (as highlighted again in a recent WTO ruling).
More on the impact of sugar cane plantations on freshwater >>