Cellulose, lignin and nitrogen concentrations as rate regulating factors in late stages of forest litter decomposition

Abstract

MCCLAUGHERTY, C., and B. BERG, 1987. Cellulose, lignin and nitrogen concentrations as rate re- gulating factors in late stages of forest litter decomposition. Pedobiologia 30, 101—112. Mass loss and changes in chemical composition during the decay of a variety of forest litters decomposing at several very different sites were measured. The data were used to examine general factors that regulate patterns and rates of decay in late stages of decomposition. The fraction of holocellulose in lignocellulose, termed the holocellulose to lignocellulose quotient (HLQ), is pre- sented as an index for describing the relative amount of readily available carbon during decay. In later stages of decomposition, the HLQ was positively correlated with litter mass loss rates, and as the HLQ-values declined during decomposition, mass loss rates also declined. There was also a negative linear relationship between nitrogen concentrations and mass loss rates in later stages. These findings are discussed relative to the physiology of litter degrading microorganisms.