Decomposition of cellulose in the superpáramo environment of Ecuador

Decomposition activity of soil along a 400 m altitudinal gradient in the superpáramo of the Guagua Pichincha volcano, Ecuador, was studied employing the method of cellulose decomposition. Nylon-bags containing sheets of cellulose (filter-paper) were exposed in the field at the start of the dry season and were randomly collected at four monthly intervals. Sets of cellulose-bags were also placed in cushions of “Azorella pedunculata” at two different altitudes. The amount of decayed cellulose and the litter disappearance rates (LDR) were estimated. The decomposition of the cellulose generally decreased with altitude. However, at both ends of the gradient this trend was not evident due to the particular microenvironment of the respective sites. The effect of the dry season evidenced by decrease in the LDR was detected at the two lowest sites. The material decayed more slowly in the cushions than in the soil. The ecological significance of the cushion growth-form in terms of a nutrient supply is outlined.