Abstract: The flower colors, flavonoid components and contents in five species of Camellia section Chrysantha, including Camellia nitidissima, C. microcarpa,C. achrysantha, C. longruiensis and C. longzhouensis, were measured. The flower colors were measured by CIE L*a*b*scale, and flavonoid components and contents were measured by ultra-performance liquid chromatography quadrupoletime offlight mass spectrometry. The relationship between flower colors and flavonoid components was explored by multiple linear regression analyses. Eight flavonoids weredetected in the five species. The flavonoids including pelargonium-3-O-glucoside (Pg3G), luteolin-7-O-rutinoside (Lu7R), narirutin and erodcyol were identified in the five speciesfor the first time. The quercetin-3-O-glucoside (Qu3G), quercetin-7-O-glucoside (Qu7G), quercetin-3-O-rutinoside (Qu3R) and kaempferol-3-O-glucoside (Km3G) were identified in C. microcarpa and C. achrysantha for the first time. Among the five species, the total flavonoid content of C. nitidissima was the highest, followed by C. achrysantha and C. microcarpa, and that of C. longruiensisand C. longzhouensiswere lower. Qu3G, Qu3R and Pg3G were the main flavonoid components in C. nitidissima and C. microcarpa. Qu3G and Qu7G were the main flavonoid components in C. achrysantha. Erodcyol and narirutin were the main flavonoid components in C. longruiensisand C. longzhouensis. We conclude that Qu3G and Qu3R were the important pigments determining the yellow coloring of petals of Camellia section Chrysantha. Erodcyol had a significantly positive correlation with red coloring of petals. Pg3G affected the brilliance of flower colors.

Key words: human activity, ecological transitional belt, landscape pattern, ecological risk assessment, risk management.