Litterfall and decomposition rates in Biosphere 2 terrestrial biomes

Litterfall and decomposition rates were examined in four terrestrial biome areas within Biosphere 2, Oracle, AZ during 1992-1993, the second year of c losure. Mean +/- S.E. of 14 areas studied was 539 +/- 105 g (dry wt.) m(-2) year(-1). Litterfall was greatest in the lowland rainforest (1317 +/- 283 g m(-2) year(-1)) and least in the sand dune desert (141 +/- 88 g m(-2) yea r (-1)). Decomposition bags were measured for 15 leaf types or mixes with a mean loss rate year of 90% per year. Decomposition rates were lowest in th e desert region. Litterfall and subsequent decomposition were a small perce ntage (similar to 7%) of Biosphere 2 respiration. (C) 1999 Elsevier Science B.V. All rights reserved.