Methods for estimating the effect of litterbag mesh size on decomposition

Abstract

Litterbag is a standard apparatus used in plant litter decomposition studies. Decreasing bag mesh size hampers litter decomposition due to exclusion of large-bodied consumers and interferences with agents of litter fragmentation. The combined use of coarse and fine mesh bags in field studies is thus relevant for assessing the contribution of macrodetritivores and microbial decomposers to litter decomposition. The present paper examines methods for analyzing the effect of litterbag mesh size on decomposition. I present here a new approach derived from a mathematical analysis of the first-order decay model (i.e. the Olson’s model) and use it to reanalyze a large dataset of litter decay rates in two different mesh size litterbags. The presented calculation method for the extent and rate of litter fragmentation overcomes several shortcomings of previously used indices. I also highlight potential pitfalls associated with using the Olson’s model to analyze the effect of litterbag mesh size on decomposition.