Photosynthetic pigments on plant bearing surfaces in the Himalayas

Abstract

The concentration of chlorophyll (a + b) and total carotenoids and their amount on unit area basis were assessed for different plant groups and plant-bearing surfaces in the Himalayas within an altitudinal range of 1500-2050 m during the wet season of the year. The concentration of pigments increased in the order: gymnospermic trees < angiospermic trees < shrubs < lower plants < herbs. The concentration in different strata of the forests Was inversely related with relative illuminance. Such special habitats as rocks with deep soil in creyices, tree-trunks with epiphytic vegetation, and grasslands, could develop as much chlorophyll (chl) per unit area as did the croplands. There was a considerable amount of variation in the vertical distribution pattern of chl among the different forest types investigated. The overall percent contribution by epiphytic flora to chl amount in several forest types was greater than or equal to the combined contribution of herb and shrub layers. The role of these special plant covers in the overall carbon cycle is unknown. One has only to imagine the vastness of the surface area covered by epiphytic flora in the Himalayas in order to appreciate their significance.