The Need for Improved Food Production
Published by Steven Novella under General Science | Link
There are two undeniable trends that impact global food production – increasing CO2 in the atmosphere is warming the planet, and the human population is growing. The former affects production, the latter demand. In both cases there are anti-scientific ideological groups hampering progress, and even denying that there is a problem.
By 2050 it is estimated t
hat the world human population will be 9.7 billion. This means we will need to produce 87% more food than we produce today. Johannes Kromdijk and Stephen P. Long argue in a recent paper
that we need to act now if we are going to avoid a serious food shortage. They argue we are “One crop breeding cycle from starvation.”
Some who deny the reality of global climate change have argued that, even if CO2 is increasing in the atmosphere, who is to say it’s a bad thing? Plants breath CO2, so increasing CO2 should just increase plant growth.
Kromdijk and Long point out that this view is naive. This is based on the simplistic thinking that if some is good then more is better (the fallacious basis of the entire supplement industry). In reality, biological systems exist in a complex homeostasis. Further, evolution is very efficient at optimizing biological systems to their current environment. If you rapidly change that environment, there may not be time for evolution to catch up.
They give this quick summary of the science:
The chloroplast accounts for the majority of leaf nitrogen in crops. Within the chloroplast about 25% of nitrogen is invested in the carboxylase, Rubisco, which catalyses the first step of CO2 assimilation. Most of the remaining nitrogen is invested in the apparatus to drive carbohydrate synthesis and regenerate ribulose-1:5-bisphosphate (RuBP), the CO2-acceptor molecule at Rubisco. At preindustrial [CO2], investment in these two aspects may have been balanced resulting in co-limitation. At today’s [CO2], there appears to be over-investment in Rubisco, and despite the counter-active effects of rising temperature and [CO2], this imbalance is predicted to worsen with global climate change.
Rising CO2 is causing an imbalance in how plants incorporate nitrogen and carbon, causing a deviation from evolved optimality. Wild plants will adapt eventually, but crops are not evolving under natural selective pressures. They change through deliberate cultivation, which means we (not nature) have to develop cultivars that are adapted to a world with higher CO2.
Sorry, global warming deniers, but rapidly changing the environment is probably not a good thing.
This brings us to the other anti-science ideology, the pro-organic, anti-GMO movement. This movement is almost entirely based on the appeal-to-nature fallacy, and scaremongering about new technology. Daniel Engber wrote in a recent commentary
that the movement is more akin to a religion, and is simply not about facts.
One of the talking points in the anti-GMO movement is that we do not need to increase our food production. We produce more than enough food today to feed the world’s population, the real problem is distribution. While this is true, it entirely misses the point – the point that Kromdijk and Long now make explicit. It actually misses two points.
The first is that agriculture has a huge footprint on the planet. According to a National Geographic study
in 2005, 40% of the Earth’s land mass is used for agriculture. All of the best land for agriculture is already being used. The same study indicates that we could potentially double the land mass used for agriculture, but we will be spreading into less desirable land, and devastating natural ecosystems in the process (mostly in Africa and South America).
Remember, we will need to produce 87% more food by 2050, and we cannot simply increase land use 87%. We need to use our land more efficiently.
The authors point out that two-thirds of the calories consumed by humans come from just four staple crops: rice, wheat, maize and soya bean. So clearly part of the solution will need to involve improved efficiency in these crops.
There are multiple potential solutions. A lot of land is used for raising animals for meat. There is some efficiency to be gained by reducing the total number of calories derived from meat. However, much of this land is used for grazing and is poorly suited for crops. In any case reducing meat consumption is probably going to be necessary.
Microfarming is another opportunity – breeding insects for food. This does not mean you will have to eat whole insects. Insect protein can be milled into a flour substitute. I haven’t tried cricket bread, but I understand it tastes just fine.
No matter what else we do, however, we also need to increase the efficiency and productivity of our major crops. This takes time.
This is the other point that the anti-GMO crowd misses – they argue that we don’t need GM technology to feed the world today, but that is not the point. We need to the technology to feed the world tomorrow.
Kromdijk and Long point out that the breeding cycle, the time it takes to develop a new cultivar and then deploy it in the field, is about 20 years. That means that any new cultivar we start developing today will become available around 2036. This further means we are coming up fast on the time necessary to develop solutions for 2050 – and the clock doesn’t stop at 2050.
No matter how you slice it, we need to prioritize agricultural efficiency and we need to be availing ourselves of every possible technology in order to do this.
Organic farming is going in the wrong direction – this is boutique farming with lower yields and therefore greater land use, catering to the well-fed. Proponents argue it is more sustainable, but that is not true if you consider land use.
I have argued before,
organic farming is an ideologically driven false dichotomy. We need to utilize whatever methods are evidence-based and produce the optimal sustainability and efficiency. Organic farming, I believe, stands in the way of that progress and is therefore bad for the environment.
Genetic engineering is one technology (no one says it is the only technology) that can be used to address this looming crisis.
This is where the paper gets pretty technical, but basically they are talking about using GM technology to develop cultivars that “Optimize photosynthetic leaf nitrogen allocation.” Essentially, they want to make photosynthesis more efficient. This will also include optimizing the sensing and incorporation of CO2 into the plant.
There are also other research programs underway to genetically improve photosynthesis in major crops
, like wheat and soy. This could improve yields 36-60%. It’s a good thing that we are not yet at the theoretical maximal efficiency for photosynthesis – turning sunlight into plant calories. But in order to take advantage of the potential to improve efficiency, there is no question that we need genetic engineering.
It is easy to dismiss warnings of future doom by appealing to the historical fact that the doomsayers have all been wrong before. This is a legitimate point – we are not always dealing with a zero-sum game, and technology and simple human cleverness has a way of changing the game and earning us another generation or century of growth.
But there are limits, and our success has come at a cost. Converting natural ecosystems to farmland (again – 40% of the Earth’s land mass) has had devastating effects on the environment and animal populations.
Earth-bound human population cannot grow forever. At some point we have to reach an equilibrium point. We also have to decide what we want to the Earth to look like at that point. It seems obvious to me that we would want to feed ourselves with the smallest amount of land possible, leaving the rest for living space and natural ecosystems.
In order to achieve this end we need to continue to use human cleverness and technology, including genetic engineering.
This means that right now it is a pretty close contest between global warming deniers and anti-GMO alarmists in terms of which ideological group will have the greater negative impact on our environment.