The Telegraph (UK)
By Prof Anthony Trewavas
October 31, 2011
By the time you read this article, the seven billionth baby will no doubt be born. Someone, perhaps the UN, will identify the precise boy or girl who will throughout their life carry this unique identity. I wish them luck and a long life, but this will only happen if we can solve the issues that continue to press from increasing population numbers. I am an optimist and I believe everyone else should be; any balanced look at out present circumstances would give rise to optimism, temporary blips in the economy or not. The necessity for providing food for the seven billion and for the nine billion expected by 2050, avoiding famine and mass starvation and the wars which inevitably would follow are only too obvious. The consequences if we don’t recognise our responsibility to the rest of the world will be dire. And yet one billion of us are badly nourished, and many starving.
The name most associated with the notion of the starving masses is that of Thomas Malthus. The 200th anniversary of his pessimistic text that saw mankind as always starving and which energised Darwin into producing “natural selection” passed in 1998. Malthus wrote at a time when the world’s population was one billion. What has seen off Malthusian views, which recur with monotonous regularity, has been the ingenuity with which mankind approaches and solves necessary problems. We have evolved with superlative abilities to concentrate on and provide solutions. The reliance on evidence-based knowledge, rather than belief, myth or fantasy, was crucial in the foiling of Malthus through the centuries, and it is what will see us through beyond 2050. Since the Malthusian period two centuries ago, crop yields have increased tenfold. As each successive billion has appeared, Malthusian prophets re-emerge to cast doubt on the human condition and to regard it as in decline. But Julian Simon, Bjorn Lomborg and more recently Matt Ridley have all documented the numerous ways in which human life has continued to improve; the cost on us, and the planet, diminish, and the benefits increase. Science and technology have underpinned this progress and will continue to do so well beyond 2050.
The last time the Jeremiahs amongst us raised the Malthusian issue was in the late 1960s; if they were to be believed then, mass starvation was around the corner. What put the fly in that particular pessimistic ointment was the Green Revolution, most associated with Norman Borlaug and collaborators at research institutes in Mexico and the Phillipines. Borlaug, a US citizen and Nobel prize winner, who died recently at the age of 95, continued to work in Africa improving agriculture in his nineties; an inspiration to any one with a belief in the future of mankind. These green revolution scientists and plant breeders inserted stem-dwarfing genes into wheat and rice. The extra resources available from reduced stem growth increased seed yield. Within a few years of these seeds being released to agriculture in the late 1960s, crop yields in India, East Asia and China shot up threefold, turning some of the countries involved into net exporters of grain instead of net importers. It is easy to estimate that if agricultural technology had been frozen at early 1960s levels, cropland would have had to increase from its present 12 per cent of the planetary land surface to 25 per cent. The only land suitable for this potential expansion was tropical rain forest which would have been put to the scythe in a desperate attempt to grow sufficient food. The effects on biodiversity, climate change and ecological services would have been savaged and our survival seriously threatened. The soil we don’t now use is toxic to crop plant growth, containing high quantities of aluminium.
The green revolution had its critics, although none suggested sensible alternatives. The heavy dependence on fertiliser, particularly nitrate and phosphate, for green revolution crops was something that will give cause for concern in the future. Easily mineable phosphate, an essential element in all life and required for good crop yields, is diminishing and may run out in 40 years’ time; we will probably have to salvage it from human waste. And the most efficient way of using the Haber Bosch process to convert atmospheric nitrogen into ammonium nitrate for fertiliser uses natural gas, ie methane. Shale gas will tide us over this particular hump, but the long-term consequence may be steep rises in price as less efficient ways using carbon dioxide are required. But if there is a message for today, Luddite objections to technological progress can really threaten mankind’s survival particularly when there is no valid reason for objection to the science involved. The importance of evidence-based knowledge as the foundation of all policy, where it is applicable, cannot be over-emphasised.
The solutions this time round have to be different. We have to double agricultural yield on the same area of ground; agricultural efficiency has to rise steeply just using the 12 per cent of the lands surface as at present. A variety, a portfolio, of approaches is envisaged. The buzzword this time is sustainable intensification. This umbrella term envisages the following. First, a requirement to prune waste, both in the agricultural and human food chains respectively. Crops lost to pests and diseases have to be further diminished. Second, there has to be better use of existing knowledge in all parts of the world. Many tropical crops lack any simple genetics for example. Third, dietary attitudes need to be influenced to reduce meat consumption. Most fish will have to be farmed sustainably. Fourth, yield gaps must be closed on under-performing land. The average wheat yields in Africa, for example, still hover around one quarter of that obtainable in Europe. New traits must be inserted into these crops and this will require biotechnology.