Humans and climate as drivers of algal community change in Windermere since 1850
Bibliographic record
Abstract
1. Historical archives, published data sets and lake sediments from the North and South Basins of Windermere were analysed to reconstruct changes in the lake and catchment since 1850 and determine the drivers of limnological variability. 2. Pastoral sheep farming has remained the dominant form of agriculture since 1850, but there was a decline in horse numbers (because of agricultural mechanisation), an increase in nitrogen fertiliser use and a doubling in sheep numbers since the 1950s. The human population in the Windermere catchment almost quadrupled between 1801 and 1921 coincident with the arrival of the railway in 1847, which led to urban expansion, sewer and piped water installation (since ∼1860s) and the development of sewage treatment systems (after 1886). 3. C : N ratios and stable isotopes of carbon in 210Pb-dated sediment cores suggested that land disturbance increased the transport of terrestrial carbon to sediments of both basins after 1870, but algae increasingly contributed to the sediment matrix after ∼1890. Nitrogen-stable isotope ratios generally declined in both basins consistent with an increase in an isotopically light source such as atmospheric N deposition or synthetic fertilisers. 4. Chlorophyll and carotenoid pigments in sediment cores showed that algal production increased gradually in the North Basin from ∼1890 to 1940 to be maintained at higher abundance thereafter. South Basin pigments changed most markedly ∼1860 (increase in cyanobacterial pigments), ∼1945 (increase in siliceous algal and chlorophyte pigments) and ∼1987 (increase in cyanobacterial pigments). 5. Redundancy and variance partitioning analyses suggested that sewage influx and the modernisation of agriculture were strongly and positively correlated with algal abundance. However, climate variables were a secondary driver of algal change in both lake basins. 6. Enrichment of the lake was caused by a combination of increases in population (after 1847), more efficient sewage disposal, intensification of agriculture and atmospheric deposition of N, which led to a greater than fivefold increase in primary production in the North Basin and marked shifts in algal communities of the South Basin. 7. After enrichment, lake phytoplankton responded markedly to fluctuations in climate. High precipitation in January–March led to lower abundance of siliceous algae (mostly Asterionella formosa) in both lake basins, possibly because A. formosa inocula were diluted, thus limiting the spring diatom bloom. 8. This combined palaeolimnological and archival study has shown that eutrophication of Windermere occurred before the start of the lake monitoring programme in 1945, but that nutrient enrichment enhanced the lake response to meteorological change. Therefore, future management of Windermere should aim for baseline conditions similar to those existing c. 1850 and consider that the control of eutrophication is essential in building resilience to future climate change.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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 teacher head, 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".