The current world population of 7.2 billion is projected to increase by one billion in the next 12 years and reach 9.6 billion by 2050, according to a United Nations (UN) report released earlier this year.
And, according to the UN food agency FAO, world farm production must rise by 60% to meet growing demand. Of course, the amount of land on the planet is not set to increase, so, it is generally agreed that farmers will need to boost agricultural yields by using more products such as fertilisers - including potash.
"In the long-term, rising population and income means the need for more food and hence more agricultural production," said Paul Burnside of consultants CRU in London.
"With declining arable land per capita, yields need to be pushed ever-higher - fertilisers are not the only way of doing this, but they still have a lot more to contribute, particularly in developing economies."
Macquarie commodities analyst Kona Haque agrees. "In the agricultural economy, potash will play an absolutely critical role going forward. We're not seeing land expand and the population is growing, so we're somehow going to have to increase the yield per area," she explained.
So, potash demand will rise in the long term; there's no doubt about that. But that's about the only straightforward fact about potash at the moment; the short-term fundamentals of the market are somewhat less clear cut.
Cartel break-up: after-effects on potash mining
This is largely down to the break-up of the world's largest potash cartel, the Belarusian Potash Company (BPC), in July 2013 when potash giant Uralkali walked away from its partnership with Belarusian state firm Belaruskali, claiming the latter had been selling the fertiliser outside their marketing deal.
Until then, the world's potash supply had been controlled by two marketing groups - BPC and Canada-based Canpotex, the offshore and marketing distribution company for the three Saskatchewan potash producers, Agrium, Mosaic and PotashCorp.
Collectively, Canpotex and BPC had accounted for about 70 percent of the global trade in potash, selling potash at nearly identical prices worldwide.
But Uralkali has now changed tack, and, since branching out on its own, has started to prioritise the quantity of potash it can sell over the price.
This is likely to significantly drive down prices worldwide, as other major producers of the fertiliser start to chase market share.
Indeed, Uralkali believes the price could drop by 25% to less than $300 per tonne, from around $400 when they left the cartel, potentially reshaping the potash industry landscape entirely.
But is this really likely? For Burnside, in the short-term, it is certainly possible. "Having the world's largest producer publicly state the level that it expects prices to fall to is to some extent going to be a self-fulfilling prophecy," he said.
"Market activity has been very limited since the news, because suppliers are waiting to see if Uralkali backs up its words with actions, while buyers are cautious about buying at modest discounts because they expect prices to fall further."
In fact, there is even potential for the price to fall to less than than Uralkali's predicted $300 per tonne. "The risk is that if major players genuinely attempt to operate flat out then demand won't be enough to support prices, which could fall to the marginal cost of production," Burnside explained. "Depending on how demand responds, this would mean prices below $200 per tonne."
However, according to Haque, this is an unlikely outcome. "If you do see prices fall freely lower, then I think some of the high cost capacity may stay offline, and so, in a way, that automatically provides a flaw," she remarked. "I don't think we're likely to see the big lows in prices people think will automatically happen because of the cartel break-up."
Long term: a more balanced potash industry
Certainly, in the long term, the market is likely to balance itself out. "Uralkali has clearly made this move because it believes it will put in it a stronger position in the medium to long term. If it deters capacity investment and restores demand growth, then this could well be the case," Burnside noted.
"However, potash is not a scarce resource and so providing there is enough support from prices, we won't see capacity struggle to meet demand in the long-term."
This is clearly what BHP Billiton is counting on. The world's biggest miner is continuing with its Jansen project in Western Canada, which would be the world's largest potash mine when it opens, despite the current market upheaval.
"BHP Billiton believes that building Jansen, or at least keeping it as an option, is worth it," Burnside remarked. "It has greatly reduced the capital intensity of the project, not only by lengthening the construction schedule but also by attempting to bring in a partner. By this less aggressive approach, it is also indicating that it wants to avoid a period of cost-driven pricing (and hence industry rationalisation) and rather to take advantage of longer term market growth."
Haque, too, believes this is a good decision on BHP Billiton's part. "They're taking the view that by that stage there will be so many different dynamics affecting the market," she said.
"Perhaps even their own cost of production could have fallen, in which case they would become a very competitive player. Ultimately, the long term theme of population growth is still there and at some point you are going to need more suppliers."
In the meantime, it's the farmers who are set to benefit in the short-term. "Lower prices are, of course, good news for consumers, and we may see higher volumes as a result," Burnside said.
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