The Role of<i>Prosopis</i>in Ecological and Landscape Change in the Samaca Basin, Lower Ica Valley, South Coast Peru from the Early Horizon to the Late Intermediate Period
Bibliographic record
Abstract
Abstract The lower Ica Valley on the hyperarid south coast of Peru is today largely depopulated and bereft of cultivation, yet its extensive archaeological remains attest to substantial prehispanic populations. This paper describes archaeological investigations to retrace changes in geomorphology, ecology, and land-use in Samaca, one of the riparian oasis basins of the lower Río lea, with the aim of investigating when, how, and why such changes took place. Archaeological interpretations of culture change in the region often invoke the impacts of major ENSO perturbations (El Niño). While our investigations confirm that major El Niño events around the end of the Early Intermediate Period likely offer part of the explanation for marked landscape change in the Samaca Basin, we also demonstrate the significance of more gradual, human-induced destruction of Prosopis pallida (huarango) riparian dry-forest. Huarango is a remarkable leguminous hardwood that lives for over a millennium and provides forage, fuel, and food. Moreover, it plays a crucial role in integrating fragile desert ecosystems, enhancing soil fertility and moisture, and accomplishing desalination and microclimatic amelioration. We propose that south coast valleys remained densely forested well into the Early Intermediate Period, attenuating the impact of El Niño events and supporting hitherto underappreciated agroforestry adaptations. Gradual deforestation eventually crossed an environmental threshold: river and wind erosion increased dramatically and precipitated radical desertification, feeding back into cultural changes in the Middle Horizon. Thus we argue Prosopis-human ecological relationships merit proper recognition in our archaeological interpretations of the south coast of Peru.
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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| 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 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".