Smash hit

Population levels are growing so fast already that an extra six million people are born every month. Growing enough food for everyone was further challenged, he said, because of climate change, which was likely to lead to a shortage of water.

Scientists say that intense dry spells will become more frequent over the next century. The supply of water will be put under further pressure because of the increased number of people who need it, not only to drink but to keep their crops alive. The production of a tonne of wheat, for example, requires 50 tonnes of water.

Because it was almost impossible to control the population increase in the short term, Professor Beddington told the conference, other measures would need to be taken. “Agriculture has been doing pretty well against the population size but things are changing now and they are changing quite dramatically,” he said.

“Don’t we need to do something about food? Demand has grown enormously, particularly in China and India, where much of the driving force is increased demand. By 2030 energy demand is going to be up by 50 per cent and demand for food is going to be up by 50 per cent.”

The increase in demand has been reflected by the rapid rise in the prices of basic commodities, including wheat, over the past two years.

Biofuels have been put forward as a means of reducing the greenhouse gas emissions pumped out by fossil fuels but recent studies have questioned their impact when all factors, such as the use of fertilisers on the crops, are taken into account. Critics have been angered by the loss of tropical rainforests, which have been cleared to allow farmers to grow biofuel crops.

Deforestation has been calculated to account for about 18 per cent of world greenhouse gas emissions and Professor Beddington said that to destroy rainforests in order to grow biofuel crops was “insane”. He added: “Some of the biofuels are hopeless, in the sense that the idea that you cut down rainforest to actually grow biofuels seems profoundly stupid.” He said that human ingenuity was extraordinary and he was confident that food production could be boosted, including by growing genetically modified crops.

Josette Sheeran, executive director of the World Food Programme, told the European Parliament in Brussels yesterday: “The shift to biofuels production has diverted lands out of the food chain. Food prices such as palm oil in Africa are now set at fuel prices. It may be a bonanza for farmers – I hope it is true – but in the short term, the world’s poorest are hit hard.”

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