SHANGHAI, Aug 25 (Reuters) - China and Hong Kong stocks tracked Asian markets lower on Friday, as investors braced for the risk of a hawkish tilt in the U.S. monetary policy, while worries about China's economic health linger.

** Most sectors in China fell but environment protection-related shares stood out on bets they would benefit from Japan's move to discharge treated radioactive water from the wrecked Fukushima nuclear plant into the Pacific Ocean. Property shares jumped in afternoon trading on new mortgage rules.

** China's bluechip CSI300 Index and the Shanghai Composite Index fell 0.4% and 0.6%, respectively. Hong Kong's Hang Seng Index lost 1.4%.

** Asian stocks sold off following overnight drop on Wall Street as investors were nervous ahead of Federal Reserve Chair Jerome Powell's speech at Jackson Hole.

** Lingering concerns over China's economic weakness outweighed Beijing's fresh gestures to support sinking stock.

** China's securities watchdog said it had met the country's social security fund as well as big banks and insurers to guide more long-term capital into the stock market.

** The market also ignored news that more listed companies are announcing share buybacks, and that a growing number of brokerages are cutting fees to reduce the cost of trading.

** Morgan Stanley's move to cut its price target for MSCI China weighed on sentiment.

** The Wall Street bank announced the downgrade a week after it lowered its economic growth forecast for China this year after disappointing economic data.

** Chinese environment protection stocks, however, rose, as investors expected the sector to benefit from the Fukushima discharge.

** GreenTech Environmental Co surged 14%, while Wave Cyber Shanghai Co and CEC Environmental Protection Co jumped 10% and 5.1%, respectively.

** China and Hong Kong property stocks rose after China published detailed rules on securing first-home mortgages. (Reporting by Shanghai Newsroom; Editing by Rashmi Aich)