Needlenose

Depleted versus rich topsoil

There have been a series of interesting articles recently regarding the future of agriculture, and it’s not what you’d think.  In fact some future trends seem rather ancient.

First let’s start with the key problem.  Today’s methods, let’s call them 2.0, aren’t sustainable.  Current methods cause major erosion and lead to loss of topsoil and exhaustion of the land.  And topsoil recovery is a slow process, growing maybe as fast as 3cm/year in wet conditions and significantly more slowly in arid conditions.

Key nutrients are lost as well due to our ‘flooding’ irrigation techniques combined with radically modified urban and suburban land use that speeds runoff water along with key nutrients towards the ocean, rather than capturing them on land.  One such ingredient is phosphorus.  Worried about ‘peak oil?”  Well you can live without oil, but the food we eat needs phosphorus, and scientists are already talking about hitting peak phosphorus in 25-75 years unless we take steps to recapture it.

Potassium, another key ingredient, is a bit more plentiful but current irrigation practices leach that from soil as well.  Ironically land’s loss is the ocean’s loss as well, as injecting large amounts of these plant nutrients leads to fish-killing algal blooms – in large amounts these are awful pollutants.

So where does agriculture need to go?  Back to the Future.  One interesting trend is ‘no-till’ agriculture.  Before there was tilling, our distant proto-urban ancestors used a pointed stick to dig a hole in the ground to plant a seed.  The benefit here is that if you don’t breakup the sod, you don’t get erosion and you don’t lose most of your key nutrients to runoff.  Read the linked article, there is a bit more tech (and less effort) involved in today’s no-till than poking holes in the ground with a pointy-stick.

The other trend, while also ‘old school’ requires a bit more high tech to achieve reasonably high yields – moving towards perennial crops and away from annual crops.  Most of our current foodstuffs are annuals as is all our cereals.  However, some cereals have perennial variants that scientists are breeding or tinkering with (thus the high tech), to bring yields up to levels closer to annual crops.

This is a complementary trend to the no-till as growing a perennial is essentially a no-till operation.  It has the added benefit though of enhancing soil nutrients throw nitrogen-fixing and further stabilizing the topsoil through complicated root structures.

You know as a kid I believed the sci-fi depictions of us eating goo from tubes and robots tending hydroponic farms, but with peak oil, peak phosphorus and all the other problems that agriculture and industry 2.0 have left us with, I’m figuring the farms of the future would be far more familiar to a time-traveling denizen of Çatal Höyük than a U.S. farm from the 1960s.

Stumble it!

Tags: agriculture, algal blooms, annuals, no-till, perennials, phosphorus, potassium, runoff, sustainable agriculture

This entry was posted on Thursday, October 29th, 2009 at 11:08 am by greenboy and is filed under Food Security. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.