China plans to boost its environmental protection by investing over 3 trillion yuan (about 473.1 trillion U.S. dollars) in the 2011-2015 period, said an official with China\'s Ministry of Environmental Protection on Friday. China\'s environmental protection industry is expected to see an annual compound growth rate of 15 to 20 percent, with an annual average output value of 4.9 trillion yuan in 2011-2015, said Wu Xiaoqing, vice minister of the Ministry of Environmental Protection (MEP). Wu made the remarks on the World Low Carbon and Eco-economy Conference and Technical Exposition held on Friday in Nanchang, east China\'s Jiangxi province.