Open Collections

Crudo, Joseph

University of British Columbia

This study investigated the impacts of soil compaction and organic matter removal on soil properties and tree growth of white spruce (Picea glauca) and trembling aspen (Populus tremuloides) 22 to 26 years following treatment in a boreal ecosystem of Northeastern British Columbia (BC). The study was carried out on the white and black boreal spruce (BWBS) long-term soil productivity (LTSP) site located 34 km north of Dawson Creek, BC. Soil properties evaluated in this study included selected soil physical properties (bulk density, aggregate stability, aeration porosity) and soil chemical properties (total C, total N, pH, and polysaccharides) as well as forest floor thickness and depth of visible OM enrichment in the upper mineral layer. All of these were systematically analyzed utilizing linear mixed effects models, univariate parameters. Since at the BWBS LTSP site each plot is split between (planted) white spruce and (naturally regenerated) trembling aspen, data were analyzed separately for those two tree species. For both species, soil physical properties mainly experienced a negative impact due to compaction, while chemical properties were mainly adversely affected by the removal of organic matter. Specifically, compaction led to diminished aggregate stability parameters for spruce, highlighting the potential impediment to water movement and root penetration. Soil properties such as bulk density and air-filled porosity demonstrated signs of recovery after 22 to 26 years for both spruce and aspen. Soil organic matter removal negatively influenced nutrient content in the forest floor, emphasizing its importance for these two tree species in this northern boreal forest. For tree growth, trembling aspen exhibited a more pronounced hindrance compared to white spruce under the influence of study treatments. Both species responded with reductions in selected growth parameters, including height and diameter. The findings underscore the critical importance of limiting soil compaction during harvest and retaining site organic matter on long-term site productivity. The implications of this research extend beyond the immediate study area, offering valuable insights into forestry practices in boreal ecosystems. Addressing these concerns is imperative for the effective conservation and management of these ecosystems, ensuring the continued productivity of both soil and associated tree species.

Text

2024-04-29

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/88045

Soil Science

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/