Chemical Constituents as Rate Regulating: Initial Variation and Changes during Decomposition. New and Traditional Analytical Techniques

Abstract

The decomposition process is discussed and compared for several foliar litter species as is the three-stage model introduced in Chapter 2. The main pattern for the three-stage model appears so far to be common with a certain variation related to litter species/genus. Available information on chemical changes based on 13 CNMR supports the model. We introduce a further model without an early phase, based on spruce and oak leaf litter. The spruce/oak model may have a very short early stage and initial decomposition rate is positively related to manganese (Mn) concentrations with no relationship to N, P or S. Using available data we conclude that limit values appear to be a common part of the decomposition pattern and have been found to range between c 42 and 100% accumulated mass loss. Using available data (21 species) we found general relationships between limit values and (i) litter N concentration (negative), (ii) litter Mn concentration (positive). However, we cannot excludes strong influence of litter genus/species.