But BHP Billiton said it thought shrinking commodities demand would stabilise in 2013, including from China.
All three companies are plays on commodities demand and can be volatile.
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Strong FAI is bullish for commodities demand as increased industrial activity and construction gobbles up more cement, iron ore, crude oil and copper.
In my view, even if demand for commodities from Developed Markets softens for the balance of the year, demand for commodities from Emerging Markets should help to compensate and prevent any material reductions in commodity prices.
The most persuasive explanation for the rises and falls of commodities is demand and supply.
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Given that we live in a mostly free market, an economist would tell you the natural thing would be to increase the price, which is what usually happens to commodities when demand outstrips supply.
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For investors in commodities, a prolonged Chinese stagnation means lower demand for commodities, especially industrial commodities, and therefore lower prices.
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This position has been made even stronger as demand for commodities has skyrocketed in recent years, paced largely by demand from China, India and other developing countries.
The region is sitting on two commodities in great demand right now: Oil and cash.
While Chinese demand growth for commodities is not expected to be as robust as it has been historically, demand is expected to pick up throughout 2012.
Indeed, Glencore's rise will be strongly felt in Asia, which has demonstrated ravenous demand for commodities.
Once the rebuilding gets under way there will be a big increase in demand for commodities.
In such a scenario, speculation-boosted demand for commodities pushes prices up further, fueling more speculation.
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China's resurgent economy and renewed demand for commodities is also benefiting its Asian neighbors.
This year Gruber looks for 3.5% growth, boosted by lower rates and strong global demand for commodities.
Another way to reposition is by investing in companies that profit from the rising demand for commodities.
Moreover, growth in the global economy is causing continued demand for commodities, resulting in commodity price increases.
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In part, these woes reflect fears that China's demand for commodities, and hence commodity prices, will falter.
The U.S. recession will damage the global economy and suppress demand for commodities.
If investors think QE helps economic growth, then demand for commodities should rise.
Being young, male and an information technology specialist are all commodities that are in demand for teachers in inner-city schools.
China is Australia's largest trading partner and a slowdown in the resource hungry property market could affect demand for commodities.
China demand for commodities remains robust, but not as robust as the year before when compared to the previous 12 months.
The market on Tuesday shrugged off potentially bearish news that China has again tightened its monetary policy to reduce demand for commodities.
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That has led to concerns that demand for commodities from China may tail off and further impact prices and hurt company profits.
"The main determinant to commodities is supply and demand, " said Mr Rodgers.
This combination of feeble production and feverish consumption, the argument runs, means that demand for commodities will outpace supply for years to come.
While the US and Europe struggled to recover, the emerging nations boomed and, as they did so, demand for commodities went through the roof.
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The higher index, in theory, indicates higher demand for commodities and therefore higher prices for those raw materials being shipped, mostly, to emerging markets.
And the more direct effect is clearly on demand for commodities.
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