By Ella Cao and Lewis Jackson

BEIJING, April 20 (Reuters) - China's soybean imports from the United States rose in March from the first two months of the year as more shipments arrived after Beijing resumed purchases late last year, though volumes were still sharply lower than a year earlier.

Trade tensions had stalled Chinese buying of the U.S. autumn soybean harvest, with customs data showing no imports between September and December.

Purchases resumed after a late-October trade truce, with China buying about 12 million metric tons since then, now gradually reaching ports.

Imports from Brazil climbed in March but fell short of expectations due to tighter inspections.

KEY DETAILS:

• China brought in 1.85 million metric tons of the oilseed from the U.S. in March, up from 1.49 million tons in January-February, but down 24.2% from 2.44 million tons a year earlier, data from the General Administration of Customs showed.

• Imports from Brazil rose 47.4% in March to 1.40 million tons from 0.95 million tons, after earlier harvest delays had curbed shipments.

• Total soybean arrivals rose 14.9% in March to 4.02 million tons on the year, but remained well below analysts' expectations of around 6.4 million tons.

• In the first quarter, shipments from the U.S. fell 70.5% from a year earlier to 3.41 million tons, while imports from Brazil jumped 75.6% to 7.97 million tons.

• Imports from Argentina reached 401,405 tons in March, compared with none a year earlier.

• First quarter imports from Argentina surged to 3.73 million metric tons from 111,603 tons a year earlier, supported in part by a buying frenzy in September after Buenos Aires scrapped export taxes.