Abstract: In this paper, the leaf cold resistance ability of two mangrove species Kandelia candel and Aegiceras corniculatum growing on Jiulongjiang Estuary of Fujian Province was measured by conductivity method, and the relationship of this ability with the contents of leaf water, chlorophyll and soluble protein and the activity of peroxidase during overwintering period was studied. The results show that the cold resistance ability of these two mangrove species from September 1988 to April 1989 is increased with decreasing of air temperature, and reached their maximums in January and December, respectively.Their half lethal temperature is respectively -9.3 and -9.0℃.After winter, the cold resistance ability is decreased dramatically with the rise of air temperature. The increase of the cold resistance ability is related with the increase of bound water or the decrease of free water content in leaf. Both the soluble protein content and the peroxidase activity have a similar variation trend to the cold resistance ability. The ratio of leaf bound water to free water and the ratio of leaf chlorophyll a to chlorophyll b may reflect the cold resistance ability of these two mangrove species: the higher the both are, the stronger the cold resistance ability is.

Key words: forest type, Cold resistance ability, Half lethal tmperature, Mangrove, Overwintering, soil microbial biomass carbon, Cunninghamia lanceolata., soil dissolved organic matter