"Goldman Sachs recently forecast a looming natural resources crisis, based on years of underinvestment and the tight credit conditions of the financial crisis.

"Amongst the comments Goldman makes in its research report:

1. Commodity prices will remain high and volatile, with each subsequent spike higher than the last. 
2. As the economy recovers,  so will commodity demand. 
3. China is consuming a large share of global natural resource supplies, with metals and agriculture in its crosshairs. At the top of this list are cotton, soybeans, copper and zinc, of which China consumes roughly a quarter to a third of the world's output of each, and is also a net importer. 

"Goldman also suggests investors look at engineering and construction as well as machinery companies that are uniquely positioned to address supply constraints. I agree. 

"And it's why I recommend you add to your natural resource portfolio by purchasing shares in Joy Global, a leading manufacturer of mining equipment with a strong presence in coal and copper mining, two of China's most needed commodities. 

"Trading at just over 11 times earnings -- and with sales soaring to $953 billion in the third quarter this year, more than 6% ahead of last year and 50% ahead of 2007 --  I think Joy Global's shares are a great way to play the mining equipment sector — again, in two hot commodities China desperately needs."