* Jan-July imports at 54.89 mln T, up nearly 17 pct on year
* Large July volumes due to tax change, delayed arrivals
* Arrivals expected to diminish after August, improving margins (Recasts, and adds details, comments from paragraph 4; inserts graphics and bullets)
BEIJING, Aug 8 (Reuters) - China's July soybean imports surged 30 percent to their highest level on records back to 2010, according to Reuters calculations based on customs data, as ports in the world's top oilseed consumer rushed to clear a months-long backlog of cargoes.
July imports <SB-CN-IMP> hit 10.08 million tonnes, topping the earlier highest level set in May at 9.59 million tonnes, and were up 31 percent from 7.69 million tonnes in June.
Crushers had delayed discharging bulk carriers in June due to high stocks and a change in taxes.
China brought in 54.89 million tonnes from January to July, up 16.8 percent from the same period last year, data from the General Administration of Customs also showed on Tuesday.
"Large volume of imports in July were mainly due to the change in taxes and delayed arrivals from the month before," said Tian Hao, a senior analyst with First Futures.
The surge in arrivals will raise concerns among major exporters, such as Brazil and the United States, about a glut, which could hurt demand from loss-making Chinese crushers over the next few months.
The big shipments have already put pressure on crush margins in China, which turned negative in February. Margins bounced to a profit briefly in July before returning to the red.
Crushers in Shandong, a major production hub in the country, currently lose about 38 yuan ($5.67) for every tonne of soybeans they process. <CNSOY-RZO-MRG> In June, the losses were at their highest in three years.
Major Chinese soybean buyers have also been forced to resell more than 500,000 tonnes of product in recent weeks, amid growing concerns about negative margins and congestion at Shandong province's major port of Rizhao.
Supplies are expected to start diminishing from this month, analysts said, which would take some pressure off already high stocks and help crush margins recover.
"Margins are expected to recover as stocks of soybeans and soymeal will start going down gradually from August," said Liang Yong, analyst with Galaxy Futures.
"But the recovery won't be much, probably back to the balance point, as stocks are really high now and demand from the animal farming industry remains weak," Liang said before the data was released.
Soymeal is a primary ingredient of livestock feeds.
($1 = 6.6985 Chinese yuan)
(Reporting by Hallie Gu and Josephine Mason; Editing by Tom Hogue)