Patterns of energy content in plants from the venezuelan paramos.

Determinations of energy and ash content were made on the organs of some common plant species from an elevational gradient in the Venezuelan páramos. The results indicate differences in energy content among the life forms sampled. Giant rosette plants show the highest values in the roots while woody plants have the highest energy content in the leaves. The reproductive organs show a higher energy content than the vegetative organs. There is a tendency to increase energy content as elevation and environmental stress increase. The adaptive significance of these patterns is discussed. The high average energy value for páramo plants, 20.18 KJ/g ash free dry weight, is similar to values reported for alpine tundra plants and conifer forests.