Agriculture, Paleoenvironment, and Human Occupation in the Pacific Coastal Lowlands of Southern Mesoamerica

中美洲南部太平洋沿岸低地的农业、古环境和人类居住

• 批准号: 0409762
• 负责人: Hector Neff
• 金额: $ 4.31万
• 依托单位: California State University-Long Beach Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0409762&HistoricalAwards=false
• 关键词: Agriculture; Paleoenvironment; Human; Occupation; Pacific

With National Science Foundation support Dr. Hector Neff and his collaborators will complete the analysis of five sediment cores from Pacific coastal Guatemala that are known to span the time periods when people first began modifying the landscape for agriculture and other subsistence purposes. Preliminary results from one location suggest that people brought maize or a direct ancestor of maize to the region before 5000 B.C. and that dramatic agricultural intensification took place beginning around 3500 B.C. The signal of human modification and other landscape changes can be detected in sediment cores via the changing frequencies of plant microfossils (phytoliths and pollen) and charcoal together with variation in sedimentation rates. When people cut or burn down the tropical forest for agriculture, weeds and charcoal become more common in the record as trees and other forest species decline. Sedimentation rates also tend to increase as forest cover is removed. Maize and other agricultural crops can be identified both from pollen and phytoliths, the combined evidence providing the most secure identification (phytoliths are microscopic silica bodies that accumulate growing plants). These changes are placed in a chronological context by AMS radiocarbon dating of organic matter from selected levels in the cores. The period between 3500 B.C. and 800 B.C. in Pacific coastal Guatemala is of particular interest because it was during this period that many of the distinctive characteristics of Mesoamerican complex societies coalesced. By the end of the period, people in most locations depended heavily on maize agriculture, large sites with monumental architecture and elaborate stone sculpture were being constructed, and social stratification had appeared. The fundamental shifts in subsistence, the increased tethering of people to specific locations, and the beginning of major investment in architectural infrastructure constituted the emergence of Mesoamerican civilization. Unfortunately this Pacific region has been relatively understudied and details of the sequence are poorly known compared, for example, to the Olmec heartland on the Gulf Coast of Mexico. The work of Dr. Neff and his colleagues will both establish an environmental context for this cultural progression and provide insight into the process itself.

在美国国家科学基金会的支持下，Hector Neff博士和他的合作者将完成对危地马拉太平洋沿岸五个沉积物岩心的分析，这些岩心跨越了人类最初开始为农业和其他生存目的而改变景观的时期。从一个地点获得的初步结果表明，人们在公元前5000年之前将玉米或玉米的直系祖先带到该地区，而戏剧性的农业集约化从公元前3500年左右开始。通过植物微化石（植物岩和花粉）和木炭的变化频率以及沉积速率的变化，可以在沉积物岩心中检测到人类改造和其他景观变化的信号。当人们为了农业而砍伐或烧毁热带森林时，随着树木和其他森林物种的减少，杂草和木炭在记录中变得更加普遍。随着森林覆盖的消失，沉积速率也趋于增加。玉米和其他农作物可以通过花粉和植物岩进行鉴定，这两种结合的证据提供了最可靠的鉴定（植物岩是生长植物聚集的微观硅体）。这些变化是通过AMS放射性碳定年法对岩心中选定水平的有机物进行年代测定而确定的。在公元前3500年到公元前800年之间的太平洋沿岸危地马拉，人们对这段时期特别感兴趣，因为正是在这段时期，中美洲复杂社会的许多鲜明特征融合在一起。到这一时期末期，大多数地区的人们严重依赖于玉米农业，建造了带有纪念性建筑和精致石雕的大型遗址，社会分层出现了。生存方式的根本转变，人们越来越多地聚集在特定的地方，以及对建筑基础设施的重大投资的开始，构成了中美洲文明的出现。不幸的是，这个太平洋地区的研究相对不足，与墨西哥墨西哥湾沿岸的奥尔梅克中心地带相比，对序列的细节知之甚少。内夫博士和他的同事们的工作将为这种文化进步建立一个环境背景，并提供对过程本身的洞察。