Collaborative Research: Reconstructing Prehistoric Land-Use Patterns in the Lower Rio Verde Valley, Oaxaca, Mexico

保存在湖泊和湿地中的沉积和生物材料提供了丰富的生态档案，记录了过去因气候变化或人为影响而导致的植被群落的变化。它们还可以提供关于过去人类社会是如何组织的以及他们如何利用自然资源的见解。里奥维德早期农业景观项目(RVEAL项目)的重点是在景观尺度上了解史前土地利用动态。这项研究将重建墨西哥瓦哈卡州下里奥维德山谷近4000年来的植被和农业历史。从河谷的十个河口、湖泊和考古环境中收集了沉积物岩心。该项目将在每个地点进行详细的多代理古生态调查。研究人员将分析沉积物地层、宏观和微观木炭、花粉、植硅体和稳定的碳同位素特征，以记录史前农业造成的植被和土地利用变化。将在关键的地层位置对沉积物岩心进行放射性碳测年，以制定年代学。多代理分析将以准十年抽样间隔进行。详细的古生态数据将补充现有的考古数据，从而提供一个独特的机会，在空间尺度上了解史前土地利用模式，直接与山谷内的社会和政治变化相媲美。传统上，中美洲的土地利用历史是通过对湖泊沉积物的单点古生态分析获得的，由此重建了对植被分布和农业用林地的广泛的区域理解。RVEAL项目超越了这种区域分析，将重点放在利用古生态记录在当地景观尺度上的重建上。这项研究将能够建立一个复杂的理解土地利用和景观变化的多标度模型，将对短期和局部过程的理解与长期、区域过程的理解结合起来。该项目将为研究人类长期使用土地对热带生态系统的影响作出重要贡献，并将使用一个理论框架，以便在其他地方开展类似的研究活动。该项目将为美国和墨西哥的本科生和研究生提供研究机会。研究小组还与地球博物馆的工作人员合作，开发详细介绍研究过程和发现的博物馆展品。

Sedimentary and biological materials preserved in lakes and wetlands provide an ecologically rich archive of past changes in vegetation communities resulting from climate changes or anthropogenic impacts. They may also provide insights into how past human societies were organized and how they used natural resources. The focus of the Río Verde Early Agricultural Landscape Project (Project RVEAL) is to understand prehistoric land use dynamics at landscape scales. The research will reconstruct the vegetation and agricultural history of the Lower Río Verde Valley, Oaxaca, Mexico for the last ~4000 years. Sediment cores have been collected from ten estuarine, lake and archaeological settings in the valley. The project will undertake detailed multi-proxy paleoecological investigations at each site. Researchers will analyze the sediment stratigraphy, macroscopic and microscopic charcoal, pollen, phytoliths and stable carbon isotope signatures to document vegetation and land use changes resulting from prehistoric agriculture. The sediment cores will be radiocarbon dated at key stratigraphic locations in order to develop a chronology. The multi-proxy analyses will be undertaken at a quasi-decadal sampling interval. The detailed paleoecological data will complement existing archaeological data and thus provide a unique opportunity to understand prehistoric land use patterns at a spatial scale that is directly comparable to social and political changes within the valley. Traditionally prehispanic land use history in Mesoamerica is derived from single site paleoecological analyses of lake sediments by which broad scale regional understandings of vegetation distribution and forest clearance for agriculture are reconstructed. Project RVEAL moves beyond this regional analysis and will focus on reconstruction at the local landscape scale using the paleoecological record. The research will enable the construction of a sophisticated multiscalar model of prehispanic land use and landscape change that integrates understandings of short-term and local processes with long-term, regional ones. The project will provide an important contribution to research on the impacts of prolonged human land use in tropical ecosystems and will use a theoretical framework that may permit implementation of comparable research activities elsewhere. This project will offer research opportunities for both American and Mexican undergraduate and graduate students. The research team is also partnering with personnel at the Museum of the Earth to develop museum exhibits detailing the research process and findings.