Data from: Biomass and nutrient dynamics of fine litter of terrestrially rooted and epiphytic material in a neotropical montane forest, Costa Rica

To investigate the importance of the epiphyte community to ecosystem
nutrient cycling, we assessed the standing crop, input rates, and turnover
rates of litterfall derived from epiphytic material and compared them to
litterfall derived from terrestrially rooted material in a neotropical
cloud forest in Monteverde, Costa Rica. The standing crop of fallen
epiphytic material in 1988 was 0.5 t ha-1and 0.3 t ha-1in 1990. Annual
input of fallen epiphytic material was 0.5 t ha-1, more than two times as
much as has been reported for other tropical cloud forests. This is
equivalent to 5-10 percent of total fine litter at the site (7.5 t ha-1).
Nutrient input from fallen epiphytic material was (kg ha-1yr-1): N, 7.5
(7% of nutrient transfer via total fine litter); P, 0.5 (8%); Ca, 4.2
(4%); Mg, 0.8 (5%); and K, 0.1 (1%). Assuming a steady state condition in
this old-growth forest, epiphyte-derived litter biomass had a higher
annual decay rate (Ka= 1.3) than did litter derived from terrestrially
rooted plants (0.7). However, turnover time (1/Ka) of all nutrients except
K in fallen epiphytic material was four to six times slower than for
nutrients in terrestrially rooted material; K was tenfold faster. Over
half of the fallen epiphytic material was collected in less than 2 percent
of the collections, indicating the deposition of epiphytic material is
highly sporadic in space and time and must be measured at the appropriate
spatial scale.