Professor Jules Pretty gave a fascinating and wide-ranging insight into the sustainable intensification of agriculture on Tuesday afternoon; this year’s BES Lecture. Prof. Pretty suggested that there was an ‘emerging consensus’ around the necessity of improving agricultural productivity whilst minimising harm to the environment – as testified by recent reports from the Foresight Land Use Futures programme, the Royal Society and others.
By 2050, the Foresight report has concluded, a 50-100% increase in food production will be needed worldwide to feed a growing human population. The precise figure will depend on how fast and far the population grows and on the consumption patterns which emerge. Food choices are currently converging. Where these were previously divergent, driven by choices and norms informed by differences in culture, now a Western ideal of consumption dominates, informing a greater consumption of meat in China, for example. Food price spikes in recent years have also adversely and disproportionately affected the poor and the hungry. Such trends will only continue unless radical reform is made to the systems by which we currently produce food, which involve intensive application of fertilisers, an increased use of machinery and a huge growth in livestock for meat and dairy which themselves eat grain which could be used to feed the hungry.
Prof. Pretty argued that we need to move from an ‘either, or’ approach, which has dominated discussions to date and has damaged ecology and policy, to ‘both, and’ arguments in which interventions and approaches are combined with one another, rather than one or another being adopted exclusively and at the expense of the environment. We need to consider genetic factors, agro-ecological factors and social and institutional factors when moving towards sustainable intensification.
Very importantly, as highlighted by Prof. Pretty throughout his talk, we need to build social capital – the networks of trust that bind people together and lubricate co-operation. Social capital includes common rules, norms and sanctions for behaviour. Research by Jilly Hall, a PhD student of Professor Pretty’s, has shown that in the UK those farms on which the farmers have the greatest social capital are those where sustainability is greatest. Social capital is evidenced by large social networks with a great deal of face-to-face contact. Social capital in the farming sector has however been eroded since the late 1980’s, with the closure of a national agricultural extension service, which previously saw the development of networks of trust between farmers and those from Government who would attend the farm to deliver advice on the latest agricultural practices. Prof. Pretty argued that this has made policy implementation harder and slower and has impeded a transition to sustainability on many farms.
One fascinating example given by Prof. Pretty to illustrate the importance of agricultural extension was ‘farmer field schools’ in South East Asia. Run by the UN Food and Agriculture Organisation (FAO), these schools have trained four million farmers in the better application of pesticides to their rice crops. Farmers had previously been told – by pesticide companies – to spray their crops at the first sign of herbivore damage to the leaves. Scientists at the field schools have demonstrated to farmers that a rice plant can withstand damage of up to 40% of its leaves before spraying is necessary. With fewer pesticide applications, although crop yields do not significantly increase, farmers are able to save money and to run integrated crop growing – fish farming systems.
In Africa too, new farming practices are reaping benefits. In Burkina Faso and Mali agricultural extension has seen the implementation of ‘Push-Pull Integrated Pest Management’ systems in which mixed maize fields ‘pull’ predators away from the main maize crop. Desmodium is planted to repel (’push’) stemborer moths, whilst an attractant plant, napier grass, is planted as a border crop around this plant (’pull’). This ‘ecological redesign’ of agricultural systems is an excellent example of the application of ecological knowledge to improve farming practices.
Prof. Pretty suggested that the UK has much to learn from agricultural practice in Africa, as the example of the importance of social capital above demonstrates. Farmers in West Africa are beginning to adopt ‘zero tillage’ systems, with consequent benefits for water retention, carbon sequestration, the organic matter content of soils and the need for reduced inputs. In the border of Essex and Sussex, Prof. Pretty suggested, farmers have this season begun to directly sow seeds into the ground rather than to plough first, indicating that farmers in this country are also beginning to see the benefits of ‘zero tillage’.
Prof. Pretty’s conclusion was that this century is an opportunity for us as a society to transform the consumption of food. We must not however have a ‘dewey eyed’ view of an idealised countryside. Landscapes and agricultural systems have to work for those who live and farm there; if people wish to leave the countryside then the system developed probably isn’t sustainable. We need to communicate to wider society that agriculture is part of the future of this country, and internationally, not a past to leave behind as it is not part of a ‘glitzy’, service-led industry which is held up as a beacon of progress and to which people are encouraged to aspire.
BES Facebook group
