Water’s role in the protein crunch
Published June 30th, 2011
Until last year, the water-energy nexus was a big enough concern on its own. Over the past twelve months, the challenge of feeding the world’s seven billion people has been added to the mix. The essential challenge is as follows: if we want to increase energy production, we might need to use biofuels, which use a lot of water and land which could be used for growing food. If we want to increase water production, we need to use more energy in desalination, pumping groundwater and long-distance transfers. If we want to increase food production, we need more water as well as more acreage of land.
A new book published this month – Protein Crunch by Jason Drew and David Lorimer – gives an interesting new angle on the food challenge from the point of view of the rising demand for protein. “Forecasts indicate that we need to grow 50% more food by 2030 and double the amount we currently grow by 2050 to meet our changing patterns of consumption and growing population. Yet the amount of available land and water is decreasing, as is the renewable output of our seas.”
Given that one of the authors is a farmer, the book is most interesting when talking about the agricultural challenge. Specifically, they introduce the concept of soil as an additional limiting factor on global growth, alongside fossil fuels and freshwater resources. It seems that as the pressure of agriculture increases, the ability of soil to respond is decreasing for physical, chemical and biological reasons. Physically intensive agriculture is increasing water and wind erosion, with dams acting as barriers to the reuse of topsoil downstream. Chemically intensive irrigation is salinising the soil, while biologically, the increased use of fertilisers is killing the nematodes and other organisms that improve soil quality.
I don’t go along with the authors’ conclusion that the solution is for us to use less of everything. I prefer Michael Braungart’s ‘cradle-to-cradle’ remedy, which proposes that we must develop a circular economy. Instead of taking resources from nature, modifying them for use, then disposing of them, everything we use must be reused, in the same way that there is no waste in nature.
In my view, the best indicator of the sickness of the global economy is that fact that six out of the ten largest companies in the world are natural resource companies, according to the FT Global 500 2011, which was published last week. We live in a world where the scarcity of what we can take from nature is the biggest driver of value in the economy.
What is interesting is that all natural resources have some sort of cycle. Minerals might have a cycle of billions of years. Fossil fuels might have a natural cycle of millions of years. Topsoil might have a natural cycle of thousands of years (Protein Crunch estimates that it takes between 3,000 and 12,000 years to build up enough soil to make cultivatable land). Water has much the quickest natural cycle, and because of that, it can provide the key to many of the challenges we face as demand for less easily renewable resources grows.
For example, it is going to be water technology which provides the solution to the eutrophication of rivers that causes dead zones for fish, and contributes to the salinisation of arable land. It will be a challenge, but water technology can recycle the nitrates and phosphates which are the cause of the problem and turn them back into a usable fertiliser. Similarly, water technology will address the problem of the silting up of dams. We can deliver the dramatic improvements in agricultural production required in order to meet both our food and energy needs – but we need to invest more in water.
It seems to me that the water technology sector, which has hitherto focused on the problem of cleaning water for urban use, is going to get a broader brief in future. With that in mind, our American Water Summit in Atlanta this November (see www.americanwatersummit.com) will include a session on the water-food nexus. Making water work better for food is a big challenge, not least because of its diffuse nature, but let’s see how we can address it.