(Recasts lead, updates prices, adds comment, Bank of Canada announcement, changes byline)
* Dollar gains vs Canadian dollar after BoC announcement
* Australian dollar falls after Chinese stocks drop
* Focus on upcoming ECB meeting
By Dion Rabouin
NEW YORK, Oct 21 (Reuters) - Investors on Wednesday clamoured for the safety of the U.S. dollar against emerging market currencies and commodity-linked units such as Australian dollar following a slide in the Chinese stock market.
China grabbed investor attention after the Shanghai Composite stock index .SSEC closed more than 3 percent lower, slumping toward the close in a resumption of recent volatile patterns. Other emerging market stocks and their currencies were also shaky after recent data on the region hinted at a gloomy growth outlook.
The yen, meanwhile, hit a more than one week low against the greenback JPY= after Japanese trade data raised concerns about another recession in the world's third-largest economy. That helped the dollar rise to 120 yen at multiple points during the day and was last up 0.1 percent at 119.94 JPY= .
The dollar also advanced against the Australian dollar, often seen as a proxy for Chinese investments because of Australia's pronounced trade links with China. The Aussie dollar fell 0.5 percent to US$0.7214 AUD= .
The dollar's relative strength was notable, but "it is the story about commodity currencies that is much more important," said Kathy Lien, managing director of BK Asset Management in New York.
The U.S. dollar rose sharply against the Canadian dollar, gaining 1.1 percent on the day to C$1.3125. The greenback hit its highest in two weeks against the Canadian currency after the Bank of Canada held interest rates steady, but lowered growth forecasts for 2016 and 2017. ID:nL1N12L1AW
The announcement from Canada's central bank was "weighing heavily on the loonie," Lien said, and "in New Zealand, dairy prices fell, hurting the New Zealand dollar. And generally speaking commodity prices are lower across the board."
Commodities led by oil took a pounding on Wednesday, with while U.S. crude prices CLc1 hitting $44.86, their lowest levels since Oct. 2.
Against the South African rand ZAR= , the dollar gained 1.7 percent at 13.5089. It was also 0.9 percent higher versus the Brazilian real at 3.9410 reais BRL= , edging closer to a 4-to-1 currency exchange rate with Latin America's biggest economy.
There was little change for the dollar, however, against the euro, as the currency pair continued their holding pattern in anticipation of Thursday's European Central Bank monetary policy meeting. Investors expect the ECB to keep interest rates steady and hold any announcement of further policy easing given Tuesday's solid batch of euro zone data.
The euro was last flat on the day at $1.1340 EUR= .