Chinese shares closed up Wednesday ahead of the release of second quarter economic data, with the benchmark Shanghai Composite Index up 0.82 percent to end at 2,470.44 points.

The Shenzhen Stock Index rose 0.02 percent, or 1.96 points, to 9,803.72 points.

Total turnover increased to 132.66 billion yuan (19.57 billion U.S. dollars), from 127.97 billion yuan on the previous trading day.

Gainers outnumbered losers by 740 to 136 in Shanghai and 679 to 298 in Shenzhen.

The National Bureau of Statistics is expected to release a range of economic data Thursday, including the second quarter gross domestic product growth, the consumer price index and fixed assets investment.

The benchmark Shanghai Composite Index rose sharply in the morning, but pared gains in the afternoon trade, as market sentiment turned cautious over expectations of the economic data and the initial public offering of the Agricultural Bank of China (ABC), which is also scheduled to start trading on the A-share market on Thursday.

The ABC is expected to raise up to 10.12 billion U.S. dollars via the Shanghai portion of the IPO, as its A-share IPO price was set at 2.68 yuan per share.

Shanghai's local shares rebounded after witnessing a significant decline last month, on speculation of possible mergers and acquisitions among state-owned enterprises in Shanghai.

The sector gained 1.49 percent, while up to 11 stocks rose by the daily limit of 10 percent.

Banks also rose by 0.79 percent, boosted by Bank of Ningbo's forecast that the bank expected a 70 to 80 percent year on year growth in profit in the first half.

Industrial Bank gained 2.1 percent to close at 25.3 yuan, and Bank of Beijing rose 1.28 percent to 13.44 yuan.

China's largest gold producer, Zijin Mining Co., said in a statement to the Shanghai Stock Exchange Wednesday that it would extend an investigation into the acid spill at Zijinshan mine, in southeast China, that had contaminated a river and killed thousands of fish.

Luo Yinnan, president of the company, said Zijin Mining would compensate fish farmers for their losses and had suspended production at the mine.

Shares of the company close flat at 5.76 yuan on Wednesday.

Analysts are expecting China's economic growth to slow down in the second quarter as the effects of the government's massive stimulus package weaken.

Pei Changhong, head of the Institute of Finance and Trade Economics of the Chinese Academy of Social Sciences, has forecast second-quarter growth to slow to 10.6 percent from 11.9 percent in the first quarter.