| dc.description.abstract | Residual forest biomass is a viable feedstock that can be used in the
bioenergy stream. There remains, however, a concern that excessive removal of
forest biomass may have negative impacts on forest biodiversity, stand
regeneration, tree growth, soil nutrient availability, and foliar nutrition. This study
examines the effects of different amounts of biomass removed from clear-cut
harvested, 2nd growth black spruce (Picea mariana) plantations. The specific
questions addressed in this study were: 1. How does the level of biomass
retention influence seedling growth? 2. Are there measurable differences in soil
N availability across a gradient of biomass removals? 3. Are any of the
differences in soil N availability reflected in seedling foliar N concentrations or
content?
The study was conducted on two black spruce plantations that were
planted in 1962, and clearcut harvested in 2007. The sites represented
contrasting soil types (i.e., clay versus loam). Six biomass retention treatments
were applied in 15 x 15m treatments across 3 blocks at each site that represented a gradient of C (0 – 22 Mg ha-1
) and N (0 – 325 kg ha-1
) retention
levels. PGPs (100 m2
) were established in each treatment plot, with tree
measurements, foliar, and soil sampling done every 5 years up to year 15.
The results showed that biomass removal had little effect on the stand
and soil condition in both sites out to 15 years since establishment. The most
significant results were the differential responses across soil types, with the clay
site having better growth, soil N availability, and foliar N concentrations. These
results suggest that proper management and timing of the additional removal of
biomass as bioenergy feedstock are unlikely to have significant negative effects
on stand development and early growth. | en_US |
