Cellulose Decomposition Rates in Clear-cut and Uncut Red Pine (Pinus densiflora S. et Z.) Stands

This study was carried out to determine the effects of clear-cutting on cellulose decomposition in a 42-year-old pine (Pinus densiflora S. et. Z.) stand. The variation of cellulose mass loss with soil temperature, soil pH, soil CO2 efflux rates, soil moisture and soil organic carbon content was measured monthly for 1 year from clear-cut and uncut pine plots. Annual mean cellulose mass loss rates during the study period were generally higher (P = 0.07) in the clear-cut (3.73 mg g(-1) day(-1)) than in the uncut (2.74 mg g (-1) day (-1)) plots. Increased cellulose mass loss rates in the clear-cut could be attributed to the change of soil environmental factor such as soil temperature following canopy removal. Cellulose mass loss rates in the clearcut and the uncut plots were positively correlated with soil temperature (clear-cut: r = 0.677, P < 0.01; uncut: r = 0.702, P < 0.01) at a soil depth of 20 cm, while there was no significant correlation (P > 0.05) between cellulose mass loss and soil water or soil organic carbon content. The results indicate that soil temperature is a key variable on increased cellulose mass loss rates following canopy removal in a red pine stand.