The Sustainable Food Trust recently organised a meeting to consider the question, ‘What role for grazing livestock in a world of climate change and diet-related disease?’
Videos of the presentations will be posted next week, but reports of the event are already appearing elsewhere. Elin Röös is a post-doctoral researcher at the Swedish University of Agricultural Sciences working on a Future Agriculture initiative. Her report is one of the most interesting, but also most challenging for the SFT.
SFT Policy Director, Richard Young, who organised the event, takes Elin’s report as his starting point then goes on the examine why, despite some convergence in their views, he and Elin still find themselves viewing the issues from very different perspectives and coming to different conclusions.
At first glance, the question ‘What role for grazing livestock in a world of climate change and diet-related disease?’, appears only to be about cattle, sheep and other ruminants, the impact they have on the environment and the health issues associated with red meat. But look a little closer and it becomes clear that this is one of the defining question of our time and that in attempting to answer it one has to grapple with the huge question of how the growing global population is to be fed in future, in a world where climate change and non-renewable resource depletion will progressively impact on agricultural productivity.
The pollution associated with feedlot beef finishing systems, the loss of rainforest to grazing cattle and the degradation of soils from over-grazing are very serious issues and it is not difficult to see why many people have come to view cattle as one of the most destructive aspects of agriculture, even before the issues of methane emissions, red meat and health are taken into account.
But could all this be blinding us to the vital role that grazing animals could and should be playing in the development of resilient and benign food systems, as well as healthy diets?
The SFT has in common with Elin and Professor Pete Smith from the University of Aberdeen, who gave the opening presentation, a belief that it will not in future be possible for everyone to eat as much meat as is currently eaten per head of population in developed countries. However, Elin is so convinced that cattle numbers need to be reduced that she would rather see grassland used to produce biofuel than beef.
Elin isn’t alone. Pete Smith is amongst those who argue, that due to methane emissions, the number of ruminants globally needs to be halved in order to avoid the ravages of runaway climate change. It is a powerful argument. Methane is a potent greenhouse gas, but it breaks down within a decade or so to carbon dioxide and water, unlike the other main greenhouse gases which once released persist in the atmosphere for 100 years and more. So reducing methane emissions today could bring about a measurable reduction in global warming more quickly than almost any other action that could be taken.
In marked contrast, I have previously argued that in order to make global agriculture sustainable into the future we ideally need to increase the number of grazing animals. I’m repeating that claim today not because I want to provoke further outraged reactions, but simply as shorthand for pointing out that we cannot devise a sustainable way of producing food by considering methane emissions in isolation.
But how can I possibly justify my position? Well I don’t know for certain that I can. To some extent it’s little more than intuition. Some of the research needed to answer the questions emphatically has yet to be undertaken. It may also be that as a beef cattle, sheep (and arable) farmer, I’m unable to free myself from a natural bias in considering these issues, but the presentations at our event were an attempt to begin the process of independent scientific evaluation.
I’m not going to rehearse all the points that emerged here, but what I come across so often amongst food and climate change campaigners is the belief, usually based on life cycle analyses, that if we would just eat more plants and less red meat, agriculture would miraculously become more sustainable. I do not believe this to be the case.
Methane emissions from ruminants account for about 4.5% of human-induced global warming (if we count all grazing livestock, but do not deduct the emissions from the herds of ruminants that previously roamed wild). So halving ruminant numbers could reduce anthropogenic emissions by about 2%. That’s not insignificant, but if we then ploughed the surplus grassland to grow crops and depended entirely on fertiliser for nitrogen (as would be necessary) I believe the net greenhouse gas emissions would in fact be higher.
More importantly still, we would deprive ourselves of a vital tool to correct an even more serious food security problem. Others can challenge this if they wish, but after 46 years as a farmer, I have yet to discover a way to grow staple food crops continuously on farmland without denuding soil of organic matter, structure and biological life. And such soils will be in no shape to feed us in future.
While thankfully not all soils are yet in serious trouble, the United Nations Convention to Combat Desertification has drawn attention to the fact that already over half (52%) of all food producing soils are moderately or severely degraded, the loss of arable land is running at over 30 times the historical rate, 1.9 billion hectares of farmland is now degraded, 24 billion tons of fertile soil are lost and 12 million hectares of farmland become severely degraded every year. Every day 2,000 hectares of cropland is lost to food production simply due to irrigation, which in dry regions causes water to evaporate so quickly that salts dissolved in the water build up in the soil.
You might imagine that soil degradation just relates to Africa and other naturally arid regions, but even in temperate countries like England and Wales, 37% of arable land is suffering from soil erosion rates above the tolerance value, soil carbon levels continue to decline in many fields and researchers from Sheffield University have estimated that at the current rate of soil degradation we only have enough soil left in the UK for 100 more harvests.
It seems to me that we are hell bent on making exactly the same mistakes that brought an end to a significant number of civilisations in the past including the Summerian civilization, and would even have ended the Roman Empire had not other factors done so first – that is the over-exploitation of food producing land by growing crops year after year and not returning the land periodically to grass. The only difference is they had little knowledge of soil science and what they were doing. The same cannot be said of us.
There are inspiring examples of land regeneration, from the stony fields in West Wales, to desert in Egypt and the highlands of Ethiopia. Where high value vegetable crops are grown and composted animal, human or vegetable waste are returned to the land, and farmers can afford to take land out of production for fertility building with green manures and even ungrazed grass. But look at the continuous arable cropland of Britain and the rest of Europe, look at the prairies of North and South America, Russia and Australia from which so much of our global calories come in the form of grain and other combinable crops and I challenge anyone to tell me not only how to rebuild soil carbon and restore land degradation but also how to arrest the decline, without returning the land to grass and bordering the fields with hedgerows; and to make that viable grazing animals would need to be reintroduced onto cropland on a rotational basis.
This might seem an impossible task, and so it may prove, but if that is the case the prospects for future food security will be bleak indeed.
You will find more about these issues on the Sustainable Food Trust website next week.
To find out more about the ongoing debate on ‘What meat to eat?’ click here.