Not all soil is created equal | Sumfood

Posted in Clean Eater, Consumer, Food Security on May 22, 2019

Getting Dirty

Getting your hands dirty has become the euphemism for doing dirty work – something that is unpleasant, unpopular or (in the Hollywood sense) illegal. But, getting one’s hands dirty is exactly what we need to happen for quality food production. This post is not dedicated to how unpopular such activities are (for that, have a read here). Instead, we dig deep on the issue of whether soil is important (spoiler alert: it is) and what we should be doing to protect it, starting with a bit of a cryptic question.

Goats and Soil

What do soil and goats have in common? Other than the obvious fact that soil provides the nutrients for goat food to grow, 2015 was named in both of their honour. The United Nations denoted 2015 as the International Year of Soils, it was also the Chinese year of the Goat. It is highly significant that the United Nations deemed that the state of the world’s soils was of considerable concern and that attention needed to be drawn to it.

Why dedicate a year to soil? Most of us don’t really think about it – we take it for granted, it’s what the lawn grows in, it’s what the kids walk into the house, it’s what we slip over in, it’s the stuff that farms have a lot of, people plant things in it, bugs live in it. There seems to be enough of it. Until there isn’t. Rising urban sprawl, soil erosion, contamination and pollution all impact the amount of available good soil. Good soil? But, isn’t dirt, dirt? The answer is a resounding ‘no’. Along with climate, soil composition often determines what can be grown and where. To define soil – according to the Soil Science Academy of America, soil is “a complex mixture of minerals, organic material, water, and various lifeforms”. And, not all soil is created equal, which makes how land is actually used, even more important.

Harvest versus housing

Tension between land use (specifically using land to grow food versus using land to allow houses to develop) is a global phenomenon. As an example: the US lost 11 million acres of superior growing land (land with good soil and climate) between 1992 and 2012. The shift of land use in the US is attributed to a number of factors including such things as the ageing farming population. Farming is not seen as an attractive career opportunity by many and it is often more lucrative to sell land for development than to continue to try and farm it. Regardless of the reason, highly-rated farm land is being lost disproportionately faster than less desirable land. The consequence of this is that sub-optimal land will need to be used to produce food for a growing population.

In New Zealand, the same pattern has emerged and the horticulture sector has rallied against property developers – it transpires that land that is good for growing cabbages is also prime real estate for house development. As Michelle Sands of Horticulture NZ said: "New Zealand has a growing population, and they need healthy fruit and vegetables; we cannot feed more people with less land." For those not working in horticulture it may seem that the industry response is a little ‘precious’, after all there is more land; however, not all land is created equal.

Not all soil is equal

The American Farmland Trust (AFT) makes a clear case for understanding the importance of land use – using subpar land for growing food results in “…more water, more transportation, more energy, more fertilizers, and more pesticides to be productive, all of which are bad for the environment”. The AFT define how they measure how ‘good’ land in their report Farms under Threat and note that the sustainability of farming activity requires land that is the right mix of productivity, versatility and resiliency. In this equation, productivity does not occur at the cost of the environment – in fact, excessive production at the cost of land use longevity is seen as counterproductive. Versatility means that the land is not only suitable for single use, but can support a wide variety of use and crops. The factors that contribute to versatility (soil type and physical land characteristics) are often the selling points for land developers. The final criteria; resiliency, depends upon topography, soil characteristics and climate. Again, climate and topography often form part of the marketing strategy for hungry property developers. It is ironic that real hunger that may result from this seemingly insatiable real estate hunger.

How much contamination?

It is not just what land has been used for but how it has been used, that should be of considerable concern. A recent report by the UN’s Food and Agriculture Organisation (FAO) sounds the alarm that “Industrialization, war, mining and the intensification of agriculture have all left a legacy of soil contamination across the planet” and a worrying issue is that no one seems to be able to quantify just how much of the earth is contaminated. While we don’t know how much of the earth is poisoned, the implications for future food security are serious. Healthy food cannot be grown on contaminated soil, which makes the relationship between contamination and food production critical; a fact that has been identified by the FAO as an urgent and critical issue to be addressed, specifically: "The potential of soils to cope with pollution is limited; the prevention of soil pollution should be a top priority worldwide".

It is all interconnected

There are limited reports of the scale of contamination: 80,000 sites in Australia, 19% of Chinese agricultural soils, 1,300 polluted ‘hot spots’ in the US. However, none of these statistics provide us with an indication on what the actual implication is for food production (and eating food from contaminated land should be a topic for a future blog). What we do know is that our current approach to land use needs to be modified and we need to understand and respect the interaction soil has with other eco-systems – particularly fresh water and ocean systems. It could be said that our disconnect with food systems enables the ongoing misuse of soils and encroachment of good land – perhaps it is time to look down and appreciate the basis for plant and, consequently, animal life.

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