By Tim Bearder

BBC Oxford



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The motion at the Oxford Farming Conference debate 2011 will be that unrestrained population growth and food security are incompatible.

The two keynote speakers are environmentalist Jonathon Porritt in favour and businessman Sir Paul Judge who will be speaking against.

Mr Porritt believes "it is dangerous to assume we are just going to have more and more food available us."

Sir Paul feels that limiting the global population is unrealistic.

Both parties accept that the number of people on Earth is likely to reach nine billion by the middle of this century but Mr Porritt believes everything should be done to delay that outcome.

"It would be far more sensible to start thinking about restricting population growth and heading towards fewer people on the planet rather than more people," he said.

Sir Paul does not agree that restraining population is sensible.

"Would they have a one child per couple policy like China has? Would they go round shooting people?"

'Faster reduction'

Both agree that female emancipation, education and contraception have led to a decrease in the rate of population growth.

Mr Porritt said: "I'm not in despair about the population story, I just want those successes to be universally available so that we see an even faster reduction in average fertility."

Sir Paul thinks that we need to work to feed the population we have rather than constraining it.

Conference delegates at the Oxford Union will decide whose arguments win the day when the motion is debated on Wednesday 5 January 2011.