The world's oceans and range-lands have reached their production limit and can no longer satisfy increasing demands for animal protein in the form of meat or fish, according to a leading commentator on global economics.
Unprecedented growth since 1950 cannot continue given indicators that the world "is in some trouble", and nowhere is that more obvious than with its water deficit, according to Mr Lester Brown, president of the Washington-based environmental group the World Watch Institute.
Mr Brown told the World Meat Congress hosted by Bord Bia in Dublin that red meat production had peaked with range-lands at or beyond optimal animal-carrying capacity. "Over-grazing is as common as over-fishing," he warned - which left the feeding of grain (with its high level of water usage) as the only land-based option to meet demand. Equally, the law of diminishing returns had set in with fertiliser usage.
There were indications that the 1995 level of fishing was all that was sustainable, with all 15 of the world's major oceans being fished at or beyond capacity, though aquaculture was likely to exceed beef output within six years. Capacity for increased pork and poultry production was likely to be constrained by grain output.
Perhaps the most underestimated threat was depletion of the water table, with a report to be published by the institute in July showing a global deficit of 160 billion tonnes of water a year. The US, China, India and the Middle East accounted for most of this by their use of more water than is replaced. The speculators had already seen the implications, with large tracts of lands in California being bought purely because of their attached "water rights" and George Soros buying a million acres in Argentina.
There were indications that the climate change problem may be out of control, he said. No one would have believed a prediction that in 1998 close to $100 billion of weather-related damage would occur and 300 million people would be displaced. Meanwhile, species were disappearing at a higher rate than at any time going back 65 million years to the time of the dinosaurs - further indicating all was not well.
Predictions of a global jump in population to nine billion by 2050 would not materialise against such a background. In addition, disease, hunger and conflict would intervene. The level of AIDS in Africa, and its spread to Asia, were likely to eliminate up to 25 per cent of populations, "barring a medical miracle", he predicted.
The unprecedented growth from the 1950s to now - with growth in 1997 exceeding that for the entire 17th century - and new demands on the globe meant "the future is not going to be a simple extrapolation of the past". He always wondered why there was a close relationship between increased income and increased meat consumption. He believed it was related to man's "inate desire for animal protein". This reflected our evolution as hunter/gatherers. "If we had only been gatherers, we might not have made it." The healthiest people were those in the middle of the food chain; eating grain and meat in moderation. That was why "the Mediterranean diet" was so popular, Mr Brown said. The US may be at the top of the food chain and spending most on healthcare but life expectancy was greater in Italy.
On redirecting the global economy, he said even oil companies were now accepting there had to be a shift from a carbon-based to a hydrogen-based economy with a significant solar and wind energy input. A major challenge was to get farmers to think about water-efficient technologies and to "price water so as to encourage more efficient use" though this was "not politically easy".
