Changes in organic chemical components of needle litter during decomposition. Long-term decomposition in a Scots pine forest. I

Abstract

The decomposition and organic chemical changes in Scots pine (Pinus silvestris) needle litter were studied for a period of 5 years and until 75% weight loss was reached in field incubation. The changes in components such as various groups of lipophilic extractives, low-molecular carbohydrates, cyclitols, phenolic glycosides, polysaccarides, and lignin were followed. There was a great drop of sugars, steryl esters, and triglycerides during the 1st year of decomposition. Some isoprenoid alcohols, sterols, and some acids belonged to the most stable of the soluble components. Of the solid residue the arabinans decomposed rapidly, the cellulose decomposed somewhat faster than the hemicelluloses as a group, and the lignin decomposed rather slowly (about 48% in 5 years).