Dr Colin McClung, ex-IRI, was co-recipient of the World Food prize in 2006 for this soil fertility work.

ECONOMIST: Letters

Biodiversity, which includes species, ecosystems, and ecological processes, is essential for the long-term maintenance of ecosystem services like photosynthesis, nutrient recycling, soil fertility, provision of fresh water, disaster prevention, and many others.

FORBES: Conservation International: Stemming the Tide of Environmental Crises, Part Five

Cumbria Wildlife Trust and a group of volunteers restored a hay meadow at Row Foot, Ravenstonedale, after tests showed the soil had low fertility.

BBC: Cumbria wildflowers thrive after hay meadow restoration

As we head back out into the paddy fields, he lights a clove-scented cigarette and points to the shadowy, still-active volcano that shares its name with him - Gunung Agung, the tallest, most sacred mountain on Bali, from which rivers are said to flow and the volcanic soil gains its rich fertility.

BBC: High spirits in Bali

Food is ground zero-the place where the economy meets the soil, where profitability meets fertility.

FORBES: Slow Money Movement Reports Steady Growth

Their grandfather probably exploited the great fertility that is American soil, dropped his plough, and then moved on to the Midwest and exploited it all over again.

WSJ: Dan Barber's Culinary Crusade