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

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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.

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In particular, massive use of nitrogenous fertilisers which draw multiple crops from Punjab's rather poor soil has reduced the soil's overall fertility and led to widespread soil erosion.

ECONOMIST: Punjabis are poisoning themselves

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.

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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.

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