{
  "abstract": "Stratified benthic deposits offer crucial modern analogs for Precambrian biogeochemical dynamics, yet whether the vertical organization of deep sedimentary columns reflects depositional history, present-day geochemical conditions, or both remains poorly understood, particularly under extreme oligotrophy. Here, we present a depth-resolved exploratory survey of a continuous 34-cm sediment core partitioned into 11 discrete horizons (L1 to L11) from Poza Roja 2, an alkaline, sub-hypersaline pond in the Cuatro Cienegas Basin, Mexico. Integrating physical stratigraphy, organic carbon and nutrient stoichiometry, and 16S rRNA gene metabarcoding, we evaluated down-core microbial community structure alongside acute phosphorus scarcity. Molar C:Po and N:Po ratios exceeded canonical Redfield proportions (106:16:1) in every layer, by up to 48.5-fold and 87.8-fold, respectively, both peaking in layer L4. Unconstrained ordination (PCoA) and hierarchical clustering grouped the layers into three compositional zones: upper (L2-L4), intermediate (L5-L6), and basal (L8-L11), with L1 and L7 occupying transitional positions. Archaea accounted for 31.0% of prokaryotic reads, ranging from 8.3% (L5) to 43.7% (L9), and were dominated by SM1-50 (Thermoplasmatota) and Halobacteriota. The phototrophic heliobacterium Heliorestis peaked in the intermediate zone (47.6% of bacterial reads in L6). Constrained Redundancy Analysis models lacked statistical significance (P >= 0.12), highlighting the exploratory nature of a single core (n = 11). This pilot characterization provides a baseline for understanding deep biogenic archives under severe nutrient limitation.",
  "abstract_shown": true,
  "affiliations": [
    "Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV), Unidad Irapuato"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "name": "A. Gonzalez-Sanchez"
    },
    {
      "name": "G. Ibarra-Arzave"
    },
    {
      "name": "A. Paniagua-Vargas"
    },
    {
      "name": "F. Garcia-Oliva"
    },
    {
      "affs": [
        0
      ],
      "name": "G. Olmedo-Alvarez"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8amzawkchk991.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.04.756594",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.756594v1.full",
  "id": "8amzawkchk991",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.756594v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "microbiology"
    ],
    [
      "openalex",
      "2303|Microbial Community Ecology and Physiology"
    ]
  ],
  "openalex": "W7220442172",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.10.04.756594v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-04",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8amzawkchk991.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:26:07Z",
      "native_id": "10.64898/2026.10.04.756594",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.10.04.756594v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:microbiology",
      "subfield": "microbiology"
    }
  ],
  "title": "Depth-Resolved Microbial Community Structure and Phosphorus Deficiency Across a 34-cm Mat-Sediment Core in Poza Roja 2, Cuatrocienegas",
  "title_text": "Depth-Resolved Microbial Community Structure and Phosphorus Deficiency Across a 34-cm Mat-Sediment Core in Poza Roja 2, Cuatrocienegas",
  "type": "preprint",
  "updated_at": "2026-10-30T12:26:07Z",
  "url": "https://research.draconitic.com/paper/8amzawkchk991",
  "venue": "bioRxiv",
  "versions": []
}