Changes in chemical components of leaf litter of Ginkgo biloba during mulching

Abstract

The biological decomposition and chemical changes of leaf litter of Ginkgo biloba both at the surface and bottom layers were studied for 1 year. The changes in components such as the yields of 80% ethanol and water extractives, neutral sugars, uronic acids, Klason residues, acid-soluble phenolics, ash, nitrogen, and carbon were investigated. There were great drops of the yields of 80% ethanol extractives and water extractives in both surface and bottom mulch layers. Klason residues and sugars were the major components of the solid residues. The Klason residues lost 2.2% and 30.5% of their initial mass at the surface and bottom layers, respectively, during mulching. The total losses of the neutral sugars were 71.6% at the surface layer and 89.3% at the bottom layer. These results implied that the Klason residues were the most important inner component restraining the decomposition of the leaf litter of G. biloba and all analyzed cell wall components at the bottom layer had faster decomposition rates than those at the surface layer. Nitrogen content increased during one year of mulching, while changes in carbon contents were less than 1% throughout experiment.