Mother Earth in a fix...

Here's another sombre thought: as world population goes north, the immediate need will be for more food. Which means agriculture. Which brings with it associated greenhouse gas emissions.

Humans are cultivating almost 40 percent of the land surface of the earth, and nearly a third of all the greenhouse gas emissions that are warming the planet comes from agriculture and forestry. Not all of this is due to the transport factor.

Nitrogen fertilizer, is one large source of emissions, and not only because it requires natural gas to produce. After it is spread on fields, a portion of it turns into a potent greenhouse gas, N2O that escapes into the atmosphere. Part of the nitrogen is also washed down to our rivers.

But by far the biggest contribution from agriculture is owing ot the forests replaced as land is cleared for farming. Recent changes in land use have accounted for some 25 percent of the carbon dioxide being emitted on the planet, and the bulk of those changes are driven by agriculture.

Blame it on population or blame it on the Green revolution, we have a big problem. The Green Revolution varieties were 'ecological weaklings', as an expert puts it. They had shallow roots, short stems and couldn’t compete with the weeds and needed lots of care. What is now needed is to develop varieties with deeper root systems that can survive on less water and fertilizer. Either conventional breeding or the newer genetic engineering may help, but everything comes with its own uncertainties!

This will be the biggest challenge of the coming decades - how to provide food sustainably, without damaging the environment or running out of resources? All else comes after food.