(Adds U.S. trading, commodities analyst quote; changes byline, dateline, pvs SINGAPORE/PARIS)
By Mark Weinraub
CHICAGO, Dec 15 (Reuters) - U.S. soybean futures rose on Thursday, turning higher after testing key technical support levels, traders said.
Corn and wheat futures weakened on a mild round of profit-taking. Wheat had risen for the previous five days while corn was coming off a four session winning streak.
Strong soybean exports, which highlighted the need for a big harvest in South American suppliers Brazil and Argentina, also lent support to the soy market, which had fallen for three days in a row.
"Fundamentally, the export sales have been incredibly strong and lasting for longer than I thought they would for this time of the year," said Mark Schultz, chief analyst at Northstar Commodity Investment Company.
Weather conditions in both Brazil and Argentina have been beneficial for the crop but the robust overseas demand underscores that any concerns about conditions ahead of harvest will support strong gains in soybeans, Schultz added.
The U.S. Department of Agriculture on Thursday reported that weekly soybean export sales for 2016/17 delivery rose to 2.008 million tonnes, up from 1.462 million a week ago and above trade forecasts for 1.1 million to 1.5 million tonnes.
USDA also reported a flash sale of 132,000 tonnes of soybeans to China.
At 10:22 a.m. CST (1622 GMT), Chicago Board of Trade January soybean futures were up 10 cents at $10.33-3/4 a bushel. The contract found support from early weakness at its 30-day moving average, a level it has not traded below since Nov. 18.
CBOT March wheat was down 6 cents at $4.12 a bushel and CBOT March corn shed 2-1/4 cents to $3.59-3/4 a bushel.
There was additional pressure on the grains stemming from a stronger dollar which makes commodities priced in the greenback expensive for foreign buyers holding other currencies.
The dollar rose to a 14-year peak against a basket of major currencies on anticipation of a more hawkish Federal Reserve. (Reporting by Mark Weinraub in Chicago, Naveen Thukral in Singapore and Sybille de La Hamaide in Paris; Editing by David Evans and Grant McCool)