| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4425465 | Environmental Pollution | 2011 | 7 Pages |
Soil acidification has been of concern in the oil sands region in Alberta due to increased acid deposition. Using the canopy budget model, and accounting for H+ canopy leaching by organic acids, we determined sources and sinks of H+ in throughfall in jack pine (Pinus banksiana) and trembling aspen (Populus tremuloides) stands in two watersheds from 2006 to 2009. In pine stands, H+ deposition was greater in throughfall than in bulk precipitation while the opposite was true in aspen stands. The annual H+ interception deposition was 148.8–193.8 and 49.7–70.0 molc ha−1 in pine and aspen stands, respectively; while the annual H+ canopy leaching was 127.1–128.7 and 0.0–6.0 molc ha−1, respectively. The greater H+ supply in pine stands was caused by greater interception deposition of SO42− and organic acids released from the pine canopy. Such findings have significant implications for establishing critical loads for various ecosystems in the oil sands region.
► We monitored acid deposition in the oil sands region of Alberta over three years. ► A modified canopy budget model was developed to evaluate H+ budget as the first such attempt in western Canada. ► The H+ supply by organic acid leaching from jack pine canopy was a significant source of H+. ► This has implications for establishing critical loads for acid deposition for watersheds in the region.
