Leading water scientists have issued one of the sternest warnings yet
about global food supplies, saying that the world's population may have
to switch almost completely to a vegetarian diet over the next 40 years
to avoid catastrophic shortages.
Humans derive about 20% of their protein from animal-based products
now, but this may need to drop to just 5% to feed the extra 2 billion
people expected to be alive by 2050, according to research by some of
the world's leading water scientists.
"There will not be enough water available on current croplands to
produce food for the expected 9 billion population in 2050 if we follow
current trends and changes towards diets common in western nations," the
report by Malik Falkenmark and colleagues at the Stockholm International
Water Institute (SIWI) said.
"There will be just enough water if the proportion of animal-based
foods is limited to 5% of total calories and considerable regional water
deficits can be met by a ”� reliable system of food trade."
Dire warnings of water scarcity limiting food production come as
Oxfam and the UN prepare for a possible second global food crisis in
five years. Prices for staples such as corn and wheat have risen nearly
50% on international markets since June, triggered by severe droughts in
the US and Russia, and weak monsoon rains in Asia. More than 18 million
people are already facing serious food shortages across the Sahel.
Oxfam has forecast that the price spike will have a devastating
impact in developing countries that rely heavily on food imports,
including parts of Latin America, North Africa and the Middle East. Food
shortages in 2008 led to civil unrest in 28 countries.
Adopting a vegetarian diet is one option to increase the amount of water
available to grow more food in an increasingly climate-erratic world,
the scientists said. Animal protein-rich food consumes five to 10 times
more water than a vegetarian diet. One third of the world's arable land
is used to grow crops to feed animals. Other options to feed people
include eliminating waste and increasing trade between countries in food
surplus and those in deficit.
"Nine hundred million people already go hungry and 2 billion people are
malnourished in spite of the fact that per capita food production
continues to increase," they said. "With 70% of all available water
being in agriculture, growing more food to feed an additional 2 billion
people by 2050 will place greater pressure on available water and land."
The report is being released at the start of the annual world water
conference in Stockholm, Sweden, where 2,500 politicians, UN bodies,
non-governmental groups and researchers from 120 countries meet to
address global water supply problems.
Competition for water between food production and other uses will
intensify pressure on essential resources, the scientists said. "The UN
predicts that we must increase food production by 70% by mid-century.
This will place additional pressure on our already stressed water
resources, at a time when we also need to allocate more water to satisfy
global energy demand – which is expected to rise 60% over the coming 30
years – and to generate electricity for the 1.3 billion people currently
without it," said the report.
Overeating, undernourishment and waste are all on the rise and increased
food production may face future constraints from water scarcity.
"We will need a new recipe to feed the world in the future," said the
report's editor, Anders Jägerskog.
A separate report from the International Water Management Institute
(IWMI) said the best way for countries to protect millions of farmers
from food insecurity in sub-Saharan Africa and south Asia was to help
them invest in small pumps and simple technology, rather than to develop
expensive, large-scale irrigation projects.
"We've witnessed again and again what happens to the world's poor – the
majority of whom depend on agriculture for their livelihoods and already
suffer from water scarcity – when they are at the mercy of our fragile
global food system," said Dr Colin Chartres, the director general.
"Farmers across the developing world are increasingly relying on and
benefiting from small-scale, locally-relevant water solutions. [These]
techniques could increase yields up to 300% and add tens of billions of
US dollars to household revenues across sub-Saharan Africa and south
Asia."
John Vidal is environmental editor of the Guardian newspaper.