Investigating the Impacts of Climate Change-Induced Drought on Dissolved Organic Carbon in Boreal Forest Soils and Streams
Bibliographic record
Abstract
The boreal region is a vast storage of carbon, particularly dissolved organic matter (DOM), which governs the mobilization of carbon from watersheds. Under a changing climate, fluctuations of temperature and precipitation are expected, with variability in the frequency and intensity of hydrological events such as droughts. Using a combination of a long-term data study on boreal streams and a laboratory study on boreal soils from IISD-Experimental Lakes Area, the impacts of drought events on export of dissolved organic carbon (DOC) from boreal forest soils and streams can be investigated. Event characteristics of duration and severity of dry and wet events was revealed using long-term streamflow from 1971-2023 at the IISD-ELA, by applying a standardized streamflow index (SSI) at varying timescales. The associated long term stream chemistry of DOC concentration and flux to each dry and wet event was evaluated. DOC concentration had significant relationships for dry events but only at the shorter timescales, indicating there was limited mobility under dry conditions. DOC fluxes were significantly higher during wetness events, and increases with longer timescales, this could be explained by the enhanced hydrological connectivity. Landscape specific controls was also observed where wetland dominated catchments displayed higher DOC concentration during dry periods. The findings from the laboratory study reveals the importance of considering antecedent soil moisture conditions for soil carbon dynamics. Soils were collected and separated at two different soil depths at the IISD-ELA, where soils were subjected to drying or rewetting treatment at varying intensities. The quantity (DOC concentration) and quality (SUVA254, humification index HIX, biological index BIX) was evaluated post treatments to characterize DOM composition. There was more DOC released in the drying treatment compared to rewetting treatments, specifically in the shallower and most intense treatments. In terms of DOM quality, there was more limited variation, with shifts in HIX and BIXat the deeper soils. The role of antecedent soil moisture acts as first-order control on carbon dynamics, with increasing drought severity intensifying the shifts in DOM concentration and quality. Overall, this highlights how prolonged drought conditions can play a major role for the fate of carbon in both quantity and quality found within streams and soils, and how it may impact the downstream ecosystems within boreal catchments.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".