In a study on Scots pine needle litter the degradation of single components was
followed by Berg et al. (1982a; Fig. 2.3). The onset of mass loss due to polymer
carbohydrate degradation, namely, cellulose and single hemicelluloses, began after
different periods of incubation. The degradation of arabinan and galactan begins
almost immediately after litter fall (Table 2.1). Degradation of cellulose and mannan
starts later, with the first measurable loss of these components being observed
after ca. 1 year. Figure 2.4 shows that the amount of cellulose increases before a
decrease starts, and a net decrease does not start until after about 1 year. For xylan ,
the degradation started about half a year later, while with lignin , the first net loss
was not noted until after 2 years