Long-term monitoring of Vermont’s forest soils: early trends and efforts to address innate variability
- Download PDF (1.0 MB)
- This publication is available only online.
Environmental Monitoring and Assessment
Long-term monitoring of forest soils is necessary to understand the effects of continued environmental change, including climate change, atmospheric deposition of metals, and, in many regions, recovery from acidic precipitation. A monitoring program was initiated in 2002 at five protected forest sites, primarily Spodosol soils, in Vermont, northeastern USA. Every 5 years, ten soil pits were sampled from random subplots in a 50 × 50-m plot at each site. Samples were taken by genetic horizon and, to reduce variability and improve comparability, from four specific layers: the combined Oi/Oe layer, the combined Oa/A layer, the top 10 cm of the B horizon, and 60–70 cm below the soil surface (usually the C horizon). The samples were archived and a subset analyzed for carbon, nitrogen, and exchangeable cations. After four sampling campaigns, the average coefficients of variation (CVs) at each site had a broad range, 10.7% for carbon in the Oa/A horizon to 84.3% for exchangeable Ca2+ in the B horizon. An investigation of variability within the upper 10 cm of the B horizon across a 90-cm soil pit face showed similar CVs to the entire site, emphasizing the need for consistent and careful sampling. After 15 years, temporal trends were significant in the Oa/A and B horizons at two of the five sites, with one site showing an increase in carbon concentration in both layers along with increases in both exchangeable Ca2+ and Al3+ in the B horizon, perhaps linked to recovery from acidification. The monitoring program plans to continue at 5-year intervals for the next century.
KeywordsForest soil; Soil monitoring; Acid deposition; Climate change; Soil carbon; Calcium; Aluminum
Ross, Donald S.; Bailey, Scott W.; Villars, Thomas R.; Quintana, Angelica; Wilmot, Sandy; Shanley, James B.; Halman, Joshua M.; Duncan, James A.; Bower, Jennifer A. 2021. Long-term monitoring of Vermont's forest soils: early trends and efforts to address innate variability. Environmental Monitoring and Assessment. 193: Art. 776. 22 p. https://doi.org/10.1007/s10661-021-09550-9.