Doctoral Dissertation Improvement Grant: Paleoenvironmental Context of Ancestral Puebloan Demographic and Subsistence Change in West-Central New Mexico

在万斯T.霍利迪，吉尔昂肯将调查环境变化和史前人类土地利用模式转变之间的关系，并在中西部的卡里佐沃什流域新墨西哥州。玉米农业的最初采用（公元前2100年），查科现象（公元1050-1130年）和地区人口减少（公元1300-1350年）是美国西南部普韦布洛祖先史前史中最重要的事件。然而，由于对过去环境条件的不完全理解，目前对这些关键史前事件相关的文化过程和环境的看法受到限制。了解与这些主要的生存和人口变化相关的任何环境变化的性质和程度，对于在地方和区域尺度上完善考古解释和解释至关重要。这个地质考古论文研究将需要大量的地层剖面文件。一个广泛的放射性碳测年工作将允许开发一个详细的沉积和景观历史的分水岭，将与现有的气候和考古数据相结合。沉积物，土壤，花粉，植硅石，碳同位素和树木年轮记录的分析将有助于重建广泛的环境变量，包括地貌，土壤和气候因素，影响史前玉米农业的可行性。地理信息系统（GIS）将被用来整合考古和环境数据，并检查随着时间和空间的变化土地利用，环境和农业潜力之间的关系。卡里佐沃什流域非常适合这项研究，因为它的考古研究历史悠久，西南部最古老的已知早期农业遗址之一的存在，现代河谷壁中有大量的冲积物暴露，当地集中了可确定年代的材料，并且靠近有长期的、经过充分研究的树木年轮记录的地方。西南地区全新世冲积层记录之间的广泛相似性表明，卡里佐洗环境重建将具有区域相关性，提出的跨学科研究的结果将是有用的考古学家感兴趣的史前文化变化和人类适应环境变化的许多影响，在西南地区，以及在一般的半干旱地区。这些发现对于第四纪地质学家和地貌学家来说同样重要，他们对半干旱地区的山坡和溪流如何应对气候变化感兴趣。由于广泛的侵蚀严重损害了牧场，农业和野生动物栖息地的土地生产力，这项研究也将与土地管理者有关，特别是在现代气候变化的情况下。这项研究将通过美国国家科学基金会资助的南亚利桑那州地球科学联盟学术、研究和外展（SAGUARO）计划，为属于地球科学领域代表性不足的少数群体的本科生提供研究生培训和学习机会。研究结果将通过在专业会议上发表和演讲的方式传播给科学界，并通过公共利益故事，K-12教室的演讲和/或张贴在研究区域附近社区公共建筑中的海报向公众传播。

Under the direction of Dr. Vance T. Holliday, Jill Onken will investigate the relationship between environmental change and shifting patterns in prehistoric human land use and in the Carrizo Wash watershed in west-central New Mexico. The initial adoption of maize agriculture (2100 B.C.), the Chaco Phenomenon (A.D. 1050-1130), and regional depopulation (A.D. 1300-1350) are among the most significant episodes in Ancestral Puebloan prehistory in the American Southwest. Current perspectives on the cultural processes and circumstances associated with these key prehistoric events, however, are limited by an incomplete understanding of past environmental conditions. Knowing the nature and degree of any environmental changes associated with these major subsistence and demographic changes is essential for refining archaeological interpretations and explanations at both local and regional scales. This geoarchaeological dissertation study will entail documentation of numerous stratigraphic sections. An extensive radiocarbon dating effort will permit the development of a detailed depositional and landscape history for this watershed that will be integrated with existing climatic and archaeological data. Analysis of sediment, soil, pollen, phytolith, carbon isotope, and tree ring records will contribute to the reconstruction of a wide range of environmental variables, including geomorphic, soil, and climatic factors that affected the viability of prehistoric maize agriculture. A geographic information system (GIS) will be used to integrate the archaeological and environmental data and to examine the relations among changing land use, environment, and agricultural potential over time and space.The Carrizo Wash watershed is well suited for this study because of its long history of archaeological research, the presence of one of the oldest known early agriculture sites in the Southwest, an abundance of alluvial exposures in modern arroyo walls with local concentrations of datable materials, and proximity to localities with long, well-studied tree-ring records. Broad similarities among Holocene alluvial records across the Southwest suggest that the Carrizo Wash environmental reconstruction will have regional relevance.The results of the proposed interdisciplinary study will be useful to archaeologists interested in the many influences of environmental change on prehistoric cultural change and human adaptation in the Southwest, as well as in semiarid regions in general. The findings will be equally significant to Quaternary geologists and geomorphologists interested in how hillslopes and streams respond to climate change in semiarid regions. Because land productivity for range, farming, and wildlife habitat is severely compromised by widespread erosion, this study will also be relevant to land managers, especially in light of modern climate change. This study will provide graduate student training, as well as learning opportunities for undergraduate students belonging to minority groups underrepresented in the geosciences through the Southern Arizona Geosciences Union for Academics, Research, and Outreach (SAGUARO) program funded by NSF. Results will be disseminated to the scientific community through publication in refereed journals and presentations at professional conferences and to the public through public interest stories, presentations in K-12 classrooms, and/or posters placed in public buildings in communities near the study area.