Organic and conventional agriculture can both contribute to a sustainably farmed landscape, says Tim Benton.
The world’s population is predicted to increase by 35% (PDF) by 2050. Simultaneously, per capita food demand is rising because as individual wealth increases, consumption (especially of meat and dairy) also increases. Although there are uncertainties, the most widely cited prediction for future demand is that 70% more food (PDF) will be required by 2050.
Simultaneously with demand increasing, there is recognition that agriculture needs to become more environmentally sustainable. An important utilitarian argument for sustainability is that ecosystems provide a range of goods and services, the value of which is only just beginning to be appreciated. A recent study, for example, showed that, across four US states, natural enemies control soy bean aphids to a value of $239 million per year.
Organic farming is often cited as an exemplar of sustainable farming because the environmental impact per unit area of farming is typically less than intensive systems. However, such extensive farming systems also yield less: in a recent like-for-like comparison organic winter cereal fields yielded <50% of conventionally managed fields.
This exposes a very real tension. Global food demand is rising, but so is the societal demand for lower-yielding extensive farming. To meet global demand by farming extensively is not possible as it would require more land than is (realistically) available. It has been noted that without recent decades of yield growth three times the cropped area would be needed globally and that land is not available without destroying millions of acres of rainforest.
Is sustainable farming always extensive?
To explore this tension, it is useful to think of agricultural landscapes as systems that produce two sorts of products: food and other economic goods, and ecosystem services (which may relate to biodiversity, water, carbon storage or environmental health).
In a simplistic sense, there are two basic land management strategies: land can be farmed extensively over the farmable area thereby producing less food but more ecosystem services on the same land (land sharing), or farmed intensively over a smaller area and the remaining land can be saved to be managed exclusively for ecosystem services (land sparing).
Recent research indicates that when a set amount of food is needed, land sparing strategies may often be better in terms of balancing food production while maintaining overall ecosystem services at the landscape level. In other words, if your landscape has areas specialising in food production, and areas specialising in production of ecosystem services, you get more of both than if you farm extensively over the whole landscape and try and produce both food and services from the same land.
This argument may apply at larger scales than the landscape: were Europe to increase organic farming to 20% of the total farmed area, about 10 million hectares (PDF) elsewhere (approximately the area of Portugal) would be needed to make up for the lost production. Given that this extra land is likely to be in the more biodiverse and fragile tropics, Europe may gain environmental benefits by exporting and amplifying the environmental costs elsewhere.
Future farming landscapes
Whether a land sparing or land sharing strategy is the optimal way to produce both food and ecosystem services varies from place to place and depends on the relative cost to yield converting from intensive to extensive versus the gain in ecosystem services.
Even in land sparing landscapes, where intensive methods are optimised for production, farming vistas of the future will be different from today because conventional agriculture needs to change to reduce agriculture’s carbon footprint and chemical inputs. A greening of conventional agriculture may link agronomy, information technology and remote sensing to allow low-input, low-environmental impact, but productive farming, linked with spared land managed to provide ecosystem services.
The area of spared and managed land will probably be most efficient as a network crossing the agricultural landscape, allowing the field-scale provision of ecosystem services and the resulting value for farmers, conservationists and society at large. In a nutshell, a future intensive landscape may look a bit like an existing extensive landscape.
A key policy goal is to find levers to incentivise land managers to cooperate to produce the optimal landscape. There are many routes to incentivise landscape design such as the usual tool of using agri-environmental schemes to reward land managers financially for producing ecosystem services (which they currently try to do with mixed success). The difference would be that management appropriate to the specific landscape should be rewarded, and success at delivering such objectives monitored.
I don’t think that there needs to be a societal choice between producing sufficient food with high environmental impact or producing insufficient food in a sustainable way. The landscape view of farming is a tool towards aligning the traditionally opposing camps; either extensive or intensive farming systems can contribute to a sustainably farmed landscape.
About Tim Benton
Tim Benton is Research Dean in the Faculty of Biological Sciences, University of Leeds, and is Chair of the Africa College Partnership, an interdisciplinary virtual research institute concerned with sustainable agriculture in sub-Saharan Africa. He has worked on the links between farming and biodiversity (and ecosystem services) for many years.