Land sharing and Land sparing

As day two of the South of England Show opened the winds are up and the going underfoot is slightly damp, although it was heartening to see yesterday that a worm was making its way across the floor of the International Pavilion aided by the water that had seeped through the floor material as had a solitary three leaf clover.

On listening to Farming Today as I drove along the road towards Ardingly I heard the reporter, Caz Graham, in discussion with a man, Ben Phalan from the University of Cambridge, on the potential that intensive farming could help floral and faunal biodiversity in the developing world. An article published in Science on the 2nd of September (Volume 333 no. 6047 - pp.1289-1291) examined the concepts of both land sharing and land sparing.

Land sharing integrates both the desire to meet rising food demands and the need to have less impact on the ecosystem's biodiversity whereas land sparing is where "high-yield farming is combined with protecting natural habitats from conversion to agriculture". The paper's abstract continues to state that the writers "compared crop yields and densities of bird and tree species across gradients of agricultural intensity" in two regions one in the south west of Ghana and in northern India.

The abstract concludes that "more species were negatively affected by agriculture than benefited from it, particularly among species with small global ranges. For both taxa in both countries, land sparing is a more promising strategy for minimizing negative impacts of food production, at both current and anticipated future levels of production".The full article can be read here on a subscription site.

An article found in last year's Guardian, see here, written by Damian Carrington gives us a bit more information. Land sharing is where "all the land in a region is farmed, but using wildlife friendly techniques which may dent yields a little". An example of this occurs in Europe under the premise of the Common Agricultural Policy (CAP) that "rewards farmers for giving a helping hand to animals, birds and plants that share their land, by protecting hedgerows, leaving some trees and strips for flowers and beetles". Whereas Land sparing is "some land is farmed intensively to maximise yields while other land is left entirely alone and protected as a nature reserve".

Both Damian Carrington and Ben Phelan, with his colleagues, ask the question - "Would the CAP's vast budget for land sharing schemes - €34.5bn from 2007-13 - be better spent on reserves, under the reforms now being discussed?"

Carrington answers this question by writing "The answer is we don't know, because the balance of costs and benefits between land sparing or sharing will depend on location, and the situation in the tropics and subtropics is likely to be quite different to that at higher latitudes".

But the concept of land sharing and land sparing is certainly a topic to look at greater detail in the future. Does anyone else have any thoughts or experience?