MarkSoil scientist Dr Rattan Lal, the winner of the 2020 World Food Prize for his work developing and mainstreaming a soil-centric approach to increasing food production that restores and conserves natural resources and mitigates climate change, and advocate for soil carbon has proposed ten “laws” for developing sustainable land management practices.
Here we take a look at all 10 laws through the sustainably FED lens of feeding everyone well.
Before we dive in we should say that they are not laws. There are very few laws of nature and they take a very long time before scientists can declare them as such.
Calling a set of principles ‘laws’ is clickbait but we like the attention it brings to label them boldly.
Here we go.
#1 The biophysical process of soil degradation is driven by economic, social and political forces
The FAO tells us that 40% or more of global agricultural soil is degraded. By degraded they mean the soil is not producing plant biomass at or near its potential given the climate and weather conditions.
For degradation to happen the natural flow of nutrients from the soil to plants and back again, a process mediated by the organisms and fuelled by carbon, is disrupted.
What this law suggests is that disruption comes about through land management. Farmers, foresters and other land managers make decisions on production or what to do with vegetation that is influenced by money and society.
We agree with this and it is an important realisation. Soils are actually robust to the natural effects of weather events and even climate change.
Agricultural production systems—vegetation clearing, tillage, fertiliser additions, pesticide applications—are disturbances outside the normal range for intensity and frequency.
#2 The stewardship concept is only relevant when basic necessities are met
It is often said that the farmer cannot be green if he is in the red.
The same applies to the consumer. Faced with high prices or food shortages people do what it takes to feed their families. Expediency for such a fundamental need is a powerful force.
We agree with this one and it points to concepts of universal basic income or wellbeing guarantees provided under the social contract.
#3 The nutrient and carbon pools in soils can only be maintained if all outputs are balanced by the inputs
New South Wales, the Australian state where the sustainably FED team live, is huge covering some ?? km2 that includes ?? km2 of rangeland. Sheep are the most popular livestock with 150 years of at least 40 million sheep grazing that native vegetation.
A fleece is roughly 10% nitrogen for years exported as wool to overseas markets. Fleece weight has increased over the years but a conservative 5kg means 500g of nitrogen per fleece. Assuming 100% of the herd is shawn and the minimum herd size is 40 million then 20,000 tons of nitrogen per year are exported from the soils just in wool or well over 3 million tonnes of nitrogen since 1880.
Image source: Ranc̆ić, A. (2014). Reconstruction of Bore Hydrograph Trends in Fractured Rock Aquifers Using Data Mining Techniques (Doctoral dissertation, University of South Wales).
At this scale of production in both time and space, it is hard to balance this level of output with inputs. The reality was that it did not happen and the grazing systems degraded.
#4 Marginal soils cultivated with marginal inputs produce marginal yields and support marginal living.
There is only so much potential for soil to promote plant productivity that depends on the ability of the soil to retain moisture, provide a substrate for roots and a medium to exchange nutrients.
We know what combinations of soil minerals, especially clays, and organic matter deliver efficient nutrient retention and exchange. This is settled science.
Silk purses and sow ears apply to soils too.
Land use makes the general distinctions for this law. Arable agriculture takes the good soils, grazing land the poorer soils and forestry the dregs. Other land uses grab what they can except for urban land and infrastructure that always takes priority.
#5 Plants cannot differentiate between nutrients supplied through organic or inorganic sources; it is a question of logistics, cost and availability
This is true and leads to the reality that when plants with high nutrient demand are grown—we call them crops—should the nutrient supply stop then so does the plant.
Once a production system has mined the soil of nutrients and becomes reliant on nutrient inputs this reliance is near total. Fail to supply inputs and production fails.
This is an important law.
#6 Agricultural soils can be a net source or sink for greenhouse gases depending on land use and management
We agree and can illustrate why with this graphic stylized from any number of studies that measure soil carbon before and after various land management interventions.
Image source: Alloporus & Afterbefore
The pattern is consistent everywhere. Although land management interventions do not always see an uptick in natural capital stocks or flows.
Clearing native vegetation for agriculture releases CO2, roughly a third of total human-generated greenhouse gas emissions. Soils used for agriculture tend to continue to lose carbon over time because they lack vegetation cover or are depleted as crops and livestock yields leave the paddocks.
Management to reduce tillage, keep vegetation cover, maintain deep-rooted perennial plants and water management can promote soil biological activity and raise soil carbon levels making soils a net sink.
Crucially, source or sink is a choice.
#7 CO2 released through mineralisation of soil organic matter has the same global warming effect as CO2 from burning fossil fuels.
Basic chemistry cannot lie.
#8 The yield potential of improved germplasm can be realised only if grown under optimal soils and agronomic conditions.
Intensification of agriculture is all about optimisation, the fine-tuning of production for maximum efficiency. Not optimum, maximum.
Crop varieties bred and selected for the best possible yield do not perform if the weather changes or the soil conditions deteriorate. This introduces risk to yield levels that compound the risk taken to intensify in the first place.
We like this law because it describes the reality of agricultural intensification and overlaps with laws #3, #4, and #5.
#9 Sustainable land management is the engine of economic development, political stability, and transformation of rural communities, particularly in developing countries.
We agree and would go further. Sustainable land management practices should apply to all agriculture all the time.
COVID has shown how fragile food supply chains can be and the war in Europe will only make matters worse. Food security is rapidly becoming a problem everywhere and will be acute when the rich countries start having trouble buying their food supplies—yes, UK we are looking at you.
It would be good if the land value was once again determined by its production potential. Well managed land could then trade at a premium.
Unfortunately, demand will continue to push up land value irrespective of how much food can be grown on it.
#10 Sustainable management of soil implies the use of modern innovation built upon traditional knowledge
Yes and no.
Yes because innovation is essential to retain and restore nutrient and carbon capacity in soil. Traditional methods are quaint but not always designed for long-term production especially under changing environmental conditions.
Yes because tradition has tremendous inertia. It is easier to build on agricultural practices than replace them.
No, because the assumption is that the traditional methods are worth building upon. This might be true to support a human population of fewer than 2 billion people—the number of people alive in 1900 before we started using oil in internal combustion engines. Most of these pre-industrial oil traditions were designed to feed relatively few people.
Feeding a few might not be the best place to start when there are 7.8 billion people and their pets and livestock to feed—there are 6 billion more of us than when the first gasoline-powered tractors appeared.
One in five children younger than five are ‘stunted’ – they are significantly shorter than the average for their age, as a consequence of poor nutrition or repeated infection. Photo by Nathan Dumlao on Unsplash
What sustainably FED suggests
There is nothing wrong with good law. Even a good principle that is a guide rather than a rule that regulates actions with penalties for non-compliance can help achieve a collective good.
Rattan Lal’s 10 laws for land management recognise the social reality that humans will meet their needs first. Not many people put the environment before their family or themselves, especially when they live on the margins. Humans will make resource use choices based on immediate needs.
The laws recognise the basic chemistry and physics of how soils work to produce food. Outputs need inputs or the soil is mined of its nutrients and carbon. This is common sense that is often forgotten.
The same common sense applies to genetic innovations.
People create wealth from natural capital. There is no logical reason for this to be sustainable beyond the lifetime of the individual or perhaps a family lineage. Genuine sustainability over ecological and evolutionary time is not built into nature or into human DNA.
The reality is that sustainability must be an active choice and one that might go against intuition, tradition or immediate benefit.
Applied to land management this means that we might need laws rather than principles to achieve food security.
Hero image modified from photo by Damian Denis on Unsplash
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