* CSI300 +1.1 pct; SSEC +1.5 pct; HSI: +1.1 pct
* Investors welcome decision to replace CSRC chairman
* Property, resources shares jump on gov't stimulus
SHANGHAI, Feb 22 (Reuters) - China stocks jumped 2 percent on Monday, led by property and resources shares, as investors welcomed Beijing's decision to replace the top securities regulator and on signs that the government was stepping up its economic stimulus efforts.
Both the blue-chip CSI300 index and the Shanghai Composite Index gained 2 percent by the lunch break, to 3,112.43 points and 2,918.50 points, respectively.
Mainland optimism also spilled over to Hong Kong, where the benchmark Hang Seng index rose 1.1 percent to 19,500.23, while the Hong Kong China Enterprises Index gained 1.5 percent to 8,237.54.
China said over the weekend that it had removed Xiao Gang from his post as chairman of the China Securities Regulatory Commission (CSRC), replacing him with Liu Shiyu, chairman of the Agricultural Bank of China Ltd (AgBank) .
The decision, seen as a move to restore market confidence, was cheered from China's retail investors, many of whom were burnt by the recent stock market rout.
"If a casino has a new boss and gets renovated, it's certainly something worth celebrating," said Zhu Haifeng, 31.
"I've long cast doubt about the ability of Xiao Gang. The fact that CSRC reacted to the crisis in such a passive manner showed he is a mediocre official who lacks vision."
Buying was also fuelled by hopes that China will step up stimulus to solve overcapacity problems, which the European Union Chamber of Commerce in China said have worsened since the 2008/09 global financial crisis.
Shares of Chinese property developers jumped after China said on Sunday it will reduce or stop issuing land for new residential housing projects in areas where there is a supply glut. That follows a cut in property transaction taxes announced last week.
The prospect of a stronger recovery in the real estate market, as well as signs of increasing investment in infrastructure projects, in turn triggered a surge in mainland resources shares on expectations of stronger demand for raw materials from cement to steel.
Bucking the trend in Hong Kong, though, shares of Alibaba Health Information Technology Ltd tumbled 11 percent after regulators said it would suspend Ali Health's drug monitoring platform.
Reporting by Samuel Shen and Pete Sweeney; Editing by Kim Coghill