March 4, 2011 | Robert Puro

The need to develop sustainable agriculture solutions and technologies that support topsoil development and preservation is essential to the survival of the human race. For this to happen, dirt must become a sexy cause that people feel compelled to rally around.

Perhaps the ‘Board of Dirt’ or ‘Dirt Board,’ if such a board existed, could use this tagline in its collateral to sell the sexiness of dirt.

Envision ads with famous actors and actresses with dirt mustaches, or bathing in dirt, impressing upon the people of the world just how important dirt, in particular topsoil, is to the survival of humanity.

The Importance of Topsoil

Topsoil is the top layer of soil that possesses the greatest concentration of organic matter and microorganisms.  It is around 8 inches in depth and it is where almost all of earth’s biological soil activity occurs and from which plants obtain the overwhelming majority of their nutrients.

It takes a long time for topsoil to form and replenish itself.  Estimates range from a few centuries to millennia.

And it is disappearing at an alarming rate primarily due to conventional agriculture practices such as monoculture, (the practice of planting one single crop over and over again) which saps nutrients from the soil and tillage (plowing to the layman), which artificially increases the erosion of topsoil that normally occurs as a result of wind and rain.

Currently 95% of the world’s farmers employ tilling practices to grow their crops.

Prior to the advent of conventional agriculture practices, topsoil replenished itself roughly at the same rate that it was being depleted.  Today, however, according to an article on peak soil written by University of Washington geologist, David Montgomery, “global agriculture soil loss of about a millimetre per year outpaces soil formation by at least tenfold.”

As the world’s population increases, this unsustainable rate of topsoil depletion, if it continues, will undoubtedly wreak havoc on food security around the world causing prices to skyrocket, and famine to become commonplace.  Eventually, this loss of topsoil could even bring about the end of our civilization.

Potential Solutions

This looming and dire outcome for humanity is not inevitable.  Sustainable agriculture practices and solutions currently exist to combat topsoil loss.  Chief among these sustainable practices is the no-till farming method wherein the farmer refrains from tilling his fields in between plantings and instead allows the dead organic matter from the prior planting to remain which simultaneously reduces erosion and provides a mulch for the next planting season.  According to David Montgomery no-till practices can “retard erosion by 90%.”

Additional potential solutions to topsoil loss include scientific solutions to augment the nutrient levels in soil.  According to Drake Bennett’s NYTimes article, ‘Scientists focus on making better soil to help with food concerns,’ scientists in Australia and the US have begun to study and develop methods to generate new topsoil from industrial waste.

Topsoil regeneration research has also focused on the famous terra preta or black earth found in the Amazon, which is believed to be man-made. It is composed primarily of charcoal mixed with a smattering of organic matter such as animal bones and manure or as Bennett writes in the article: “essentially the household trash of a pre-Columbian society practicing a distinctive brand of slash-and-burn agriculture.”  The study of terra preta has led researchers and a few startup companies to focus on the charcoal portion of the soil mixture, which they have rechristened ‘biochar,’ and how it can be commercialized as a supplement to replenish topsoil.

One such company producing ‘biochar’ commercially in the US is Biochar Engineering of Golden, Colorado which sells ‘biochar’ by the pallet (250 lb super sacks), barrel (90 lb char dust or 50 lb char chip), and sample bag (1 lb).   The company is also currently producing first-generation field-scale beta units for research in agricultural soil fertility, mine tailings reclamation and forest management.

The market for sustainable agriculture solutions and technologies that support topsoil development will continue to grow if people begin to give dirt the attention that it deserves and advocate alternative sustainable solutions to the prevailing conventional agricultural practices of tilling and monoculture.

Still think dirt isn’t sexy enough to get behind?