A Paleoecological Exploration of Soils in the Rio Grande Watershed of Northern New Mexico
Soils and sediments serve as valuable proxies for understanding vegetation and precipitation dynamics, as well as human impacts on the landscape over time. This thesis examines a Holocene record of environmental response to climatic shifts in two alluvial sequences (Dixon and Tesuque Creek) of the Española Basin in northern New Mexico. Radiocarbon dating along with sediment analysis, XRF, and stable carbon isotope analysis were used to reconstruct shifts in sedimentation, vegetation, and fire history. The findings corroborate with previous findings in neighboring regions. The 10,000–7000 cal BP record at Dixon broadly aligns with end of the Younger Dryas (c. 12,800–11,500 cal BP) and subsequent warming of the early Holocene. The 3720–2666 cal BP sequence at Tesuque Creek roughly corroborates with decreased δ13C (and associated decreased MAT and increased MAP) observed c. 3300–1400 cal BP in central New Mexico. Dramatic shifts in both sequences were observed across most indicators, suggesting that these proxy data were successful in detecting environmental shifts related to climate change. Understanding regional climatic and environmental shifts, as well human-environment interactions including early agriculture, can inform modern stakeholder’s decisions related to current and future land use in anticipation of an increasingly drier and hotter climate.
Weaver, R. (2022). A paleoecological exploration of soils in the Rio Grande Watershed of Northern New Mexico (Unpublished thesis). Texas State University, San Marcos, Texas.