Influence of microclimate on decomposition in loblolly pine stands: a field microcosm approach

The effect of climatic variation on decomposition was studied in a field experiment. Plexiglas microcosms were used to elevate temperatures and allow implementation of varied precipitation rates. The study was conducted in a loblolly pine (Pinustaeda L.) stand near Auburn, Alabama. Temperatures were elevated (1–8 °C depending on the season) and precipitation was varied (±30% of ambient). A litterbag approach was used to examine decomposition dynamics within the microcosms. Elevated temperatures significantly increased decomposition rates within microcosm treatments. Enhanced moisture stimulated decomposition above that associated with ambient levels of precipitation while decreased precipitation produced no significant decrease in decomposition within our temperature range. In general, litter N concentrations increased, carbon content decreased, and C/N ratios decreased over time, and these effects were accelerated when temperature was increased. Within our range of environmental factors, increases in tem...