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| Silage windrows in a field in Brastad, Lysekil Municipality, Sweden. Credit: W.Carter (CC0 1.0) |
Multiple stressors are converging to make the current industrial food system increasingly unsustainable and vulnerable to perturbations. Of course, the food system is in and of itself a leading cause to what is now threatening its future survival. Climate disruption, freshwater depletion, biodiversity loss, soil erosion and falling EROI on fossil fuels all point to the demise of industrial agriculture. This is well understood by biophysical economists and systems ecologists but often neglected in public or political discussions about food security. Most agricultural policies worsen the problem by making small-scale local agroecological farming unprofitable. Thus dooming large swathes of the population to become reliant on a dying system that costs more than it provides in terms of surplus energy.
There is a big misconception in the world about how modern technology has made us more efficient in agriculture. We think that big machines and lots of fertilizers are a better use of resources than employing more people. While large scale farming may seem efficient at first glance our perceptions are opposite of reality. How efficient the production of food is depends on the amount of energy expended on its development. The EROI, Energy Return on Investment, shows us the true nature of our efficiency in producing and consuming food.
In hunter-gatherer societies, the relevant EROI metric is the caloric value of the food captured or gathered, versus the caloric expenditure of the hunt or gathering expedition. Studies of
hunter-gatherers show an EROI of 10:1 to as high as 50:1 (
Glaub 2015,
Glaub & Hall 2017) depending on effort and final consumption. Large prey eaten directly by the hunting party only would yield a large energy profit while meat provided to support the hunters families would yield lower EROI ranging between
16:1 to 6:1. Nevertheless, this relatively large energy profit ratio probably allowed for the leisure time often associated with gathering societies. But limited capacity for food storage and settlement hinders development of a larger society.
High population and overexploitation of resources was likely a driver of early domestication. In pre-industrial agriculture, dependent on
peasant farmers, the EROI was 5:1 or less (
Day et al. 2018) as it required intense efforts over long periods with often variable results. Much time was spent on production of food, fodder and fuelwood. But farming had the benefit of food storage which led to established settlements and concentrated labour. Fuelling population growth and specializations.
Early industrialized societies benefited from high EROI from fossil fuels and large energy surpluses. Capital and energy substituted for labour. Food, fodder and fuel could be provided with fewer workers, permitting an expansion of non-primary sectors. The range of goods and services expanded. In the United Kingdom, energy and food expenditures fell to 20% as a proportion of GDP in 1830 from 50-80% prior to the industrial revolution (
Day et al. 2018). But EROI of global oil reached its maximum value of 50:1 in the 1930s and has fallen since then to about 10-15:1 today (
Court & Fizaine 2017).
Modern industrial high-tech agriculture now consumes a staggering 10 calories of energy for every calorie of energy (food) delivered to the market, i.e.
EROI of 1:10. Rending much of agriculture a net energy loss and completely unviable without fossil fuels.
As EROI of fossil fuels continues to fall an increasing amount of energy will be needed simply to provide energy and food to society. Leaving less energy over for other sectors of the economy such as education, health care etc. The only way to get out of this trap is to switch to renewable energy sources and promote small-scale, local, agroecological food production that can generate high yields but in a more diffused manner. Just like renewable energy technologies. Thus there needs to be a transition from centralised to decentralised energy and food production. Very few believe we can replace all fossil fuels with biofuels or electricity, especially in the agricultural industry that is very reliant on diesel as transport fuel. Furthermore, even if some farms could make such a shift in fuel use they would still be unsustainable if they continue to erode soils, eradicate biodiversity, deplete freshwater sources and pollute the environment. Even FAO recognizes this dilemma and now promotes
agricultural practices in line with ecosystem-based management.
Hard to put a number of food security
Politicians, journalists and pundits have for many years used the number of 50% regarding Sweden’s self-sufficiency in agriculture. A new investigation from the agricultural magazine
ATL, however, shows that this number without a doubt is incorrect. A protracted crisis with blockaded imports would result in a catastrophe.
Sweden has made itself vulnerable to shocks and disturbances in international trade by outsourcing production of basic commodities and relying on imports. The precarious global geopolitical situation have brought the question of self-sufficiency back on the political agenda.
In 2002 the last reserves and warehouses with foodstuffs in case of a national emergency were dismantled. Ten years later we read in a report from LRF that about half of all the food Swedes consume comes from imports. People have therefore assumed that Sweden has a self-sufficiency level of 50%.
But the relationship between imported and domestically produced food only shows a theoretical potential. Current stocks would only last for a maximum of 3 weeks if there is a true crisis. There are no warehouses with food and chemicals for water purification and our largest packaging plant was shut down last year, according to Therese Frisell at the National Food Agency.
In other words, Sweden is not self-sufficient at all. According to Frisell our capacity is at zero. This is due to that Sweden is heavily reliant on imports for industrial agriculture, for example oil, fertilizers and protein for animal feed.
Researchers at the Swedish University of Agricultural Sciences together with the Swedish Civil Contingencies Agency claim that farmers can produce food in a time of crisis but that this would require a large scale transition. Farmers would have to rely less on machines, switch from cereals to root crop and from pigs and chickens to uncultivated pasture meat. Farmers can not do it alone, they would need extra manpower. And if the transition fails, Sweden would likely not be able to support its growing population. People would starve.
More arid climate types raises questions about future food production
A new study in Nature shows how the world’s dry and semi-arid climate regions have expanded since 1950, mainly due to human-induced climate change. This expansion of dry regions fits with basic climate predictions. But that the trend is so broadly observable is very worrying, especially for the future of agriculture.
In “
Significant anthropogenic-induced changes of climate classes since 1950” Chan and Wu (2015) found that
5.7% of the global total land area has shifted toward warmer and drier climate types, and that this cannot be explained as natural variations. Worst impacted are highly populated mid-latitude continental climates and polar regions. According to the study, rising temperatures and decreasing precipitation both played a big role in semi-arid expansion in Asia and North America, while lack of precipitation played a bigger role in semi-arid climates in North Africa, South Africa och South America. The map below shows the globe broken down by climate types.
While semi-arid and arid regions (B) expand, extra heat in the polar regions (E) goes into thawing carbon rich frozen tundra, permafrost, with potential amplifying feedback's on climate. Even if climate predictions indeed foresaw some of this change I think many are still surprised how little global average temperature would have to increase to lead to such a massive change. Imagine how 2-3℃ would look like if “only” +0.85℃ warming (global average temperature) has lead to this!! Just look at the situation in the Middle East, with millions of refugees, lack of fresh water in almost every country that has over pumped their ground water to grow wheat in the desert for a growing population. Its insane.
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| Hydrogen sulfide emissions outside the coast of Namibia 2012. Source: NASA |
A poison or a saviour?
Hydrogen sulfide (H2S) is a colorless gas that is heavier than air, smells like rotten-eggs and very poisonous to most organisms (including humans). It results from bacterial breakdown of organic matter in the absence of oxygen, a process known as anaerobic digestion. H2S is very toxic to local marine organisms, fish die in low-oxygen (anoxic) water. The production of H2S is believed to have been one of the contributing causes to pre-historic mass extinctions (Ward, 2007). The theory is that global warming (CO2 increase in the atmosphere) lead to a slowdown in ocean currents as the temperature gradient between the poles and equator diminished, which in turn led to anoxic conditions that produced massive quantities of hydrogen sulfide, killing off vast amounts of plant and animal life. However, last year scientists found that dissolved H2S, in very small doses, can also have a growth effect on plants (Dooley et al. 2013). If correct, we may have found a way to enhance yields without using petroleum, which would be a major breakthrough for humanity.
Biological effects of H2S
The biological effects of H2S have received increasing attention during the last decade. Not only as a considered kill mechanisms during past mass extinctions but also as an important signalling molecule in organisms. While high levels of gaseous H2S kills plants, extremely low levels of liquid H2S seem to trigger a growth spurt. The origin of these dual activities remains unknown but scientists suggest it might be remnants of biological responses by life evolving in highly anoxic environments of earlier times in Earth’s history. Studies into the effects of sulfide compounds on plants are still few and most have focused on the lethal effects. It is known that H2S causes inhibition of photosynthesis at high concentrations but less is known about what happens at lower exposure.
Increasing yields
A group of scientists at University of Washington reported in 2013 that by exposing plants roots or seeds to very low concentrations of dissolved hydrogen sulfide at any stage of life caused significant increases in biomass, including higher fruit yield. The study found that germination success and seedling size increased in bean, corn, wheat and pea seeds. They also found that time to germination in seeds treated with H2S was significantly less than values observed in untreated seeds (see figure below)
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| Space Wheat seed (treated H2S seeds in the bottom) photo series taken over 119 hours |
Enhanced growth rate continued for seven days after a single exposure, followed by a return to the slower growth unless re-exposed. The H2S exposed plants reacted with cellular divisions, increasing the absolute number of chloroplasts per area. One hypothesis is that H2S does not increase growth rates as a byproduct of the addition of sulfur as a “fertilizer”, as seen through the addition of phosphates or nitrates, but actually impacts cellular replication and photosynthesis. This rapid growth behaviour may have been selected for as toxicity decreases with larger plant size. While this research is recent and further studies are needed, this could have large implications for agriculture and biofuels.
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