Changes in the cellulolytic activity of urban soils induced by the removal of plant litter (using Moscow as an example)

Abstract

The parameters of the biological activity in the upper horizons of an urban soil in Tushino (the northwestern administrative district of Moscow) without the litter horizon because of the regular removal of the plant litter and an undisturbed background Albic Retisol with the litter horizon were compared. In the studied soils, the levels and dynamics of the cellulolytic activity were comparable and generally increased from the spring to the fall seasons. This increase was more pronounced in the urban soil during the leaf fall. The seasonal dynamic of the CO2 emission in the urban soil (upon its moistening) was similar to that in the background soil, though the absolute values were significantly lower in the summer and fall seasons. The method of substrate-induced respiration (SIR) showed that the rise in the CO2 emission in response to the addition of cellulose in the urban soil was 1.5–2.0 times lower than that in the background soil. The increase in the cellulolytic activity upon the application of lime leaves (Tilia cordata Mill.) in the uppermost 5 mm of the urban soil (immediately under the leaves) was also less pronounced than that in the natural background soil. At the same time, the increase in the CO2 emission upon the addition of cellulose into this layer was more pronounced and continued for a longer time in the urban soil.