Trading in China's four commodity futures exchanges surged 22.58 percent year-on-year in the first five months of this year, the China Futures Association said on Wednesday.

The value of China's futures transactions rose to 56.6 trillion yuan (about 8.71 trillion U.S. dollars) in the Jan-May period.

In May alone, the volume of the futures transactions hit 93.81 million lots, and the transaction value gained 12.39 percent from one year earlier to 12.03 trillion yuan.

China has four futures exchanges, with agricultural commodities mainly traded on the Dalian and Zhengzhou commodity exchanges, while metals are mainly traded on the Shanghai Futures Exchange, and stock index futures contracts are traded on the China Financial Futures Exchange.

The transaction volume on the Zhengzhou Commodity Exchange in May climbed 11.12 percent to 43.66 million lots, pushing the value of transactions up 110.98 percent to 4.14 trillion yuan.

The Shanghai Futures Exchange saw its transaction volume in May drop 61.58 percent to 25.45 million lots and its transaction value was down 43.27 percent to 3.37 trillion yuan.

Transaction volume on the Dalian Commodity Exchange in May fell 15.82 percent to 21.29 million lots with the transaction value up 20.63 percent to 1.35 trillion yuan.

On the China Financial Futures Exchange, transaction volume and value hit 3.41 million lots and 3.17 trillion yuan last month, down 37.81 percent and 32.72 percent from one year earlier, respectively.