Two different timber-harvest methods are being tested on adjacent forest plots with day loam surface soils. Initially. the bulk density of the surface soil in both plots was 1.1 Mg/m3. One year after the harvest operations, plot A soil had a bulk density of 1.48 Mg/m³, whi le that in plot B was 1.29 Mg/m³. Interpret these values with regard to the relative merits of systems A and B. and the likely effects on the soil's function in the forest ecosystem.