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Solsø 1981 core area and radiocarbon lineage

The primary EPD/PANGAEA age dataset explicitly identifies event SOLSOE81, a central 1981 Livingstone core, and reports Area: 2.5 ha. This is the same numeric area and unit as the LandClim I Solsø site row. The source describes the lake as strongly drained and now mostly fen. Its area is a source-reported core-site attribute, not a dated historical lake shoreline.

The source-bound control join compares all 34 primary radiocarbon rows with the retained Neotoma controls for collection unit 4303. It matches 30 distinct primary lab controls exactly on lab number, depth (metres to centimetres), uncalibrated radiocarbon age and both errors (ka to years BP), and δ13C. Those controls occupy 54 Neotoma control rows because 24 recur in both Neotoma chronologies. The primary labels K-3970, K-4012, K-4016 and K-5634 have no retained Neotoma control; there are no conflicting values for primary labels that are present. The two remaining Neotoma control rows are not counted as primary radiocarbon matches.

The Neotoma 1981 core has two distinct age models. Chronology 25731 is the collection unit's selected EPD default, with linear interpolation in radiocarbon years BP (range 720–9790 BP); it contains 25 of the matched control rows. Chronology 25732 is Giesecke et al. 2014 (MADCAP), a clam model in calibrated radiocarbon years BP (range 0–12420 BP); it contains 29. These are records of different age models sharing radiocarbon measurements. The report pins the chronology source rows and identities. All 66 1981 source samples have an EPD default uncalibrated age claim, marked context only. The 65 samples selected for the held-out pollen study instead have comparable calibrated MADCAP claims; the remaining sample's MADCAP claim is refused because its younger bound is negative. Thus the held-out age basis follows the later model despite the collection unit's selected EPD default reference. Neither model is identified as LandClim II's author chronology.

This establishes a strong 1981 core and age-control relationship. The LandClim II 79-sample sequence still lacks an authenticated sample/core join to either of the two Neotoma cores and uses an author chronology that does not identify either Neotoma model. A 2.5 ha site area cannot supply an age-specific basin radius or correct historical water-level change. Zero Solsø samples are admitted to LRA from this join.

The 3,574-byte primary text source (SHA-256 9934dd802fa7b7094c2a6cc08fff90ef29c1c630a092787c4f4a3aac96be6be0) is retained under landclim/pangaea/solsoe/ in the external source store. PANGAEA attributes the dataset to Bent V. Odgaard and the European Pollen Database under CC BY-NC 3.0; the raw source is not redistributed in this repository. The governed report pins both that source and the Neotoma relational control part.

Reproduce from the repository root into an absent artifacts directory:

source_store="/path/to/qualified/bijux-pollenomics-data"
PYTHONDONTWRITEBYTECODE=1 .venv/bin/python -m \
  bijux_pollenomics_dev.source_completion.denmark.solsoe_core_controls \
  --repository . \
  --source-root "$source_store" \
  --source-descriptor configs/ci/qualified-report-sources/solsoe-primary-age-controls.json \
  --output artifacts/jobs/solsoe-primary-core-age-replay

The source-bound owner checks the exact retained table, all five repository lineage inputs, and their identities again before publishing the unchanged control-join report. Its declaration maps only source-products/report.json in configured reference and replay lanes. Input byte identity does not establish the table's acquisition history, broaden its noncommercial use conditions, or admit the historical author chronology or any LRA sample.