Soil health

In a March 25 2011 article for Grist online magazine (, Tom Philpott writes on the research results coming out from Pensilvania’s Rodale Institute’s ongoing Farming Systems Trial. At 27 years and running, Rodale calls this trial “America’s longest running side-by-side comparison of conventional and organic agriculture.” Besides illustrating that organic farming practices produce relatively equivalent crop yields per acre, the study has shown that organic crops resist favourably to weed pressures, drought and soil nitrogen depletion when compared to conventional crops.

What is the secret? To understand this difference, we must look no further than Sir Albert Howard who was knighted for his contributions to agronomic research. Sir Howard (1873-1947) spend over 30 years researching agricultural techniques in the then British colonies in India and thé West Indies.

Sir Howard provided the philosophical foundations for organic agriculture in his bocks An Agricultural Testament (1943) and The Soil and Health (1947), books that remains a watershed reference to this day. He believed that we must treat the ” the whole problem of health in soil, plant, animal an man as one great subject.” There can be no separation of the crop health and the health of the soils in which they live. He saw one of his favourite topics, composting, as a major element in soil fertility cycle and human health and he spent much of his treatise expounding on the benefits and methods of optimal composting in agricultural production. His works were published in thé years preceding the Green Revolution of thé 1960’s and the growth of industrial agriculture

Just as we are starting to see the bacterial colonies that share our bodies as integral to our health, we must recognize the importance of the microflora and microfauna in the topsoil as priceless in the health of our life-sustaining agricultural and wild natural systems.

David Suzuki, in his 75th anniversary 10-part CBC radio program “The Bottom Line” underlines the complexity and importance of this living system in the two part show dedicated to soil and soil health (Listen to episodes 4A and 4B). All conscientious farmers see themselves as stewards of this layer of soil and its living systems.

In the great book Feeding the Future (compiled and edited by Andrew Heintzman and the CBC’s own Evan Solomon), authors David Wheeler and Jane Thompson illustrate how conventional agriculture’s reliance on chemical inputs rather than soil stewardship progressively degrade the topsoil. In fact, the World Resources Institute estimated in 2002 that 28% of the Earth’s land surface is devoted to agriculture, of which 31% as crops and 69% as pasture. However, with current intensive agricultural practices, 49% of this agricultural land is either moderately or strongly degraded and therefore required higher levels of chemical inputs and fertilization in order to produce the necessary yields. Earthtrends research in 2003 indicated that fertilizer consumption per hectare of crop land has increased since 1960 from 10 kg per hectare (KG/HA) to more than 50 KG/HA in 2000

David R. Montgomery, a geomorphologist (geomorphology is scientific study of landforms and the processes that shape them), in his book Dirt : The Erosion of Civilizations, that soil is humanity’s most essential natural resource. Since all our food energy is based on plant transformation of solar energy into carbohydrates, fats and proteins that humans consume directly or feed to animals, several historical cases exist where soil health was neglected until crops failed leading to the collapse or weakening of the civilization in question. In the past, when soils became un-productive, populations moved on, a solution which is not an option for future generations, Montgomery warns: there isn’t enough land.

Many of our present agricultural and pollution problems can be linked in whole or in part to the reduction of topsoil health. As topsoil degrades, rainfall and wind leads to greater erosion – a process that is usually limited by the microfauna and residual root systems in a well managed soil – this erosion leads to congestion and restriction of waterways (e.g. congestion problems in the watershed of the Mississippi and Amazon rivers) . The augmented porosity and water retention of healthy soils helps reduce the need for irrigation as well as increasing drought resistance in crops planted in these soils. Monitoring of groundwater levels in intensively farmed areas in North America and India show ongoing depletion as farmers pump more and more this groundwater up for irrigation of soils that retain less and less irrigation. As runoff of weak soils increases, so does the runoff of soil nitrogen – even the added nitrogen used in chemical fertilizer. As this nitrogen (organic and inorganic) runs into the downstream watershed, it increases the incidence of algae blooms and the occurrence of oxygen deplete dead-zones where fish cannot survive.

As an individual you can help support more conscientious soil stewardship in agriculture by personally insisting on organic foods at your local grocery as well as explaining to your friends and family the importance of choosing organic and sustainably farmed produce and meats. Many economists and policy makers see organic agriculture as a luxury for the rich when in fact the short term investment we make in proper stewardship of the essential resource that is the soil will quickly pay back in crop productivity, the health of our waterways and our groundwater resources. Don’t underestimate your influence and the impact you can have when you chose action and activism – do your part today. The present federal elections present a great opportunity for activism – ask tour local and national candidates what their policies are on sustainable agricultural practices and economic support for organic farming!

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This entry was posted on 04/04/2011 at 2:45 PM and is filed under Blogue. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.