There is a debate that has been occurring for over a decade in conservation biology, but which has gotten almost no attention from the political press. The “Land sharing vs land sparing” debate. What this boils down to is the question of: how are we meant to feed the expected eleven billion people that will be alive by the end of the century and preserve biodiversity?

Land sparing proposes that we should intensify agriculture so that there is less land that is needed for agriculture. Land sharing suggests that we can have more environmentally friendly agriculture that allows biodiversity and agriculture to co-exist in the same land. The thinking is this would remain true even if biodiversity is lower than it would be in pure wilderness and yields are lower than they would be in purely agricultural landscapes. 

Although there have been few, if any, self-consciously political responses to this debate, much of the left, at least implicitly, sides with land sharing. Think of the degree to which the great environmental villains for many people are agrichemical companies that produce the pesticides and herbicides required to intensify agriculture, or the knee-jerk opposition to genetically modified organisms(GMOs) that many greens have. The “organic agriculture” movement, which has become so popular amongst a subset of the environmental movement in the last few decades, can be seen as a rejection of the very concept of land sparing. The trouble is that this position has more to do with anti-modernism and romanticism than it does with the sort of scientific protection of biodiversity that any green movement worth its salt should support. 

This may appear to be overblown, but the sorry fact is that study after study has shown that the land sharer’s dream of agricultural landscapes that support biodiversity in any meaningful sense is just that, a dream. Whether it is Ghana, Russia, Colombia, or anywhere else where a direct comparison has been made, biodiversity improvements done by having less intense agriculture are more than cancelled by the cost of having to devote more land to agriculture. From a purely scientific perspective, it seems that the environmental movement should embrace intensification of agriculture, in order to minimize the amount of land under the plow. Yet the argument doesn’t seem to die in the scientific literature, and the green left seems to be far from embracing intensified modern agriculture. 

From a scientific point of view, the argument doesn’t die because; this is science, there are still some important unknowns. The first is how to deal with the Jevons Paradox; this paradox dictates that as supply for a good increases, so too does the demand for it. This has been the case for much food in the western world. In a world where increased food supplies doesn’t mean more land is protected, then land sharing would make sense as the least bad option. The answer to this conundrum is as simple as governments regulating to curb or prevent crises relating to overproduction.

A serious problem for advocates of land sharing comes in the debate around how divided patches of biodiversity will be able to hold up over the long term. Without going into the whole theory of island biogeography; the further and smaller a patch of land is from a mainland, the more biodiversity it will lose. Under an extreme land sparing scenario, each protected area could be seen as an island, slowly haemorrhaging biodiversity since its populations cannot connect to other pockets of biodiversity. However, with careful government planning, it should be possible to design the protected areas in such a way that maximises connections between them to minimize this effect.

That is why the scientific argument is as yet unresolved. The political argument is much less complex, many environmental activists are completely divorced from anything resembling science on this issue. The mere mention of nuclear power or genetically modified crops, two of the most environmentally beneficial technologies of the last century, has time and again proven that many supposed environmentalists are more motivated by romantic notions of the countryside than any real desire to protect biodiversity. 

Under land sparing, Britain would probably lose biodiversity, which would be sad for us. But it must be acknowledged that Britain is a biodiversity desert, with no almost no endemic species. So the environmental movement has focused on what we have locally, and what we have locally tends to do best in low intensity agricultural lands

This is not a sustainable position in the long term. If we are to be part of a world that feeds the eleven billion people that will be alive at the end of the century; environmentalists should beg for this whole island to be blanketed with as much artificial wheat and maize as possible. Food to be shipped to more biodiverse countries and to ensure that land there, where there is biodiversity that matters, isn’t converted. Spare land from agriculture, and make the land that is used count.