Abstract: The role of surface coverage in tea plantation was studied in the paper. The experiment was conducted in January 2009,the coldest month in Hefei with four kinds of experiments dealing:thick straw mulching,thin straw mulching,plastic film mulching and CK. The analysis showed that there was anti-correlation between the daily minimum temperature of each experiments and solar radiation,and the anti-correlation between the mulching surface,s minimum temperature and solar radiation was stronger than that between the surface,s minimum temperature and solar radiation. The average minimum temperature was:thick straw mulching,1.2℃,thin straw mulching,1.1℃ and plastic film mulching -1.4℃,4.4℃,4.3℃ and 1.8℃ higher than CK,respectively. It indicated that the heat-preservation role of the straw mulching was stronger than plastic film mulching,and the thickness of straw mulching caused little difference. The maximum temperature of ground surface under straw mulching was lower than the plastic film mulching,mainly due to the plastic film,s permeability to the solar radiation. The difference of canopy,s leave frostbite was not obvious among each treatment. The earliest germination of spring tea was the plastic film mulching,followed by the CK and the last was the straw mulching. It could be concluded that the plastic film,s permeability was superior and the warming capacity was better than straw mulching and bare ground.

Key words: Tea plantation, Tea plantation, Straw mulching, Plastic film mulching, Surface temperature, Freeze protection