Carbon and nitrogen status of forest soils sensitive to additional biomass harvesting

The use of forest biomass to produce energy is viewed increasingly as a means to reduce fossil fuel consumption and mitigate climate warming. However, still little is known on the impact such practices on soil and site productivity. The objective of this study is to find soil properties that can explain the lower soil C and N stocks at sites subjected to whole-tree and biomass harvesting compared to stem-only harvesting. Major soil C and N losses by additional biomass harvesting occurred in in Eastern Canada only when fine silt and clay content was below 20% in soils. The separation of soil organic matter in two fractions, a recalcitrant (e.g. mineral-associated organic matter) and a more labile one (e.g. particulate organic matter) can better explain the pattern of soil C and N losses or not by additional biomass harvesting.  In brief, soil texture appears to be a major factor controlling forest soil carbon and nitrogen status in response to additional biomass harvesting.

This event is organised in the framework of the ARD CVL Sycomore Programme.