Abstract:

Chloroplast pigment content is one of important indicators reflecting relationships between plants and environment. We investigated the variation of chloroplast pigments among leaves with various ages, and the change patterns of the leaf chloroplast pigments along elevation gradients. The leaves were selected from the dominant species in Castanopsis carlessi forests in the Lingshishan national forest park. The results showed that there were significant or very significant differences of chlorophyll a, chlorophyll b, and chlorophyll (a+b) between various age leaves. Generally, the variations were more significant at middle elevation, followed by high elevation and then low elevation. The content of chlorophyll a, chlorophyll b, and chlorophyll (a+b) in two-year old leaves was higher than in one-year-old leaves. However, the variation of chlorophyll a/b and carotenoid content between different age leaves was complicated, and it indicated the adaptation of plants to environment. There were significant variations of the chlorophyll a, chlorophyll b, and chlorophyll (a+b) between different elevation gradients. With the increase of elevation gradients, the chlorophyll a, chlorophyll b, and chlorophyll (a+b) content of seven species among the dominant species increased, reaching to a maximum at the elevation of A5 or A6 and then decreased. The change patterns of chlorophyll a/b were more diversified with the increase of elevation gradients. Carotenoid, as a type of functional pigment, has complicated functions, therefore, the response patterns to elevation were diversified too. The results of this research indicated that elevation, as an important environment factor, had vital and significant impacts on plants, and that the dominant species had different adaptation strategies.

Key words: dominant species, chloroplast pigments, elevation gradients, leaf ages, Castanopsis carlessi forests, Lingshishan