People, Plants, and Landscapes in Prehistoric Ecuador: A Look at the Causes and Consequences of Agriculture

在国家科学基金会的支持下，Deborah M.Pearsall和他的同事将开展一个试点项目，研究厄瓜多尔史前沿海玉米的古老，以及环境和社会因素对农业社会的出现和发展的相互影响。利用环境取芯，该项目将研究与农业出现相关的植被、土地利用方式和生存能力的变化。西南沿海瓜亚斯省已被提议作为棉花、利马豆、南瓜和菜豆的驯化中心，并且是辣椒、可可豆、利兰、箭根、美人掌和红薯的原产地的一部分。其中许多作物出现在前冰期(9800-6700BP)和形成早期(5500-3500BP)。有证据表明，玉米在前冰期较晚，出现在形成早期的Real Alto遗址，构成了南美洲这种作物最早的日期之一。然而，根据现有的数据，很难评估玉米在形成性生存中的重要性，以及它在沿海复杂社会出现中所发挥的作用。社会从渔民采集者转变为农学家的过程对当地环境有重大影响。为了通过人类对环境影响的“窗口”充分检验关于农业的原因和后果的假设，以及玉米和其他作物在这一过程中的作用，需要8000年的环境记录。皮尔索尔和他的同事将试图通过在瓜亚斯省西南部具有早期考古遗址的三个地点进行振动，从泻湖环境中检索这些记录。将对岩心沉积物进行花粉、植物硅石(植物蛋白石二氧化硅)和沉积分析的采样，并将去除有机物质进行碳14测年。数量有限的花粉和植硅体样本将在2004年夏季田野季节之后进行处理，以评估保存质量。如果试验项目成功，将提交一份新的提案来完成这项研究。目前和未来瓜亚斯西南部的古环境研究将对我们理解农业的原因和后果做出重大贡献。它将提供一个低地、干燥的热带林区农业进化的案例研究，将对世界各地的学者有用。干燥的热带森林，例如那些曾经以西南部瓜亚岛为特征的森林，由于它们对现代农业的优势，是新大陆最濒危的生态系统之一。越来越多的证据表明，这些栖息地也是史前农业的重点，也是许多农作物的家园。史前干旱的热带森林里的农业可持续吗？这项研究的更广泛影响将是对人类随着时间的推移对森林影响的性质的洞察，以及允许人们数千年来使用这些栖息地的做法。这些发现可能适用于热带森林可持续利用的当代问题。

With National Science Foundation support, Deborah M. Pearsall and colleagues will undertake a pilot project to study the antiquity of maize in prehistoric coastal Ecuador, and the interplay of environmental and social factors for the emergence and development of agricultural societies. Using environmental coring, the project will study changes in vegetation, land-use practices, and subsistence associated with the emergence of agriculture.Southwestern coastal Guayas Province has been proposed as a center of domestication of cotton, lima bean, squash, and jackbean, and is part of the region in which chili pepper, cocoyam, lleran, arrowroot, Canna, and sweet potato originated. Many of these crops appear during the Preceramic (9800-6700 BP) and Early Formative (5500-3500 BP) periods.Evidence that maize was introduced late in the Preceramic, and was present at the Early Formative Real Alto site, constitutes one of the earliest dates for this crop in South America. It is difficult to assess the importance of maize in Formative subsistence, and the role it played in the emergence of complex societies on the coast, on the basis of available data, however.The process of transformation of societies from fisher-gatherers to agriculturalists has significant impacts on local environments. In order to test fully hypotheses concerning the causes and consequences of agriculture, and the role of maize and other crops in this process through the "window" of human impact on the environment, environmental records of 8000 years are needed.Pearsall and colleagues will attempt to retrieve such records from lagoon environments by vibracoring in three locations in southwest Guayas province with early archaeological sites. Core sediments will be sampled for pollen, phytoliths (plant opal silica), and sedimentary analysis, and organic material will be removed for carbon-14 dating. A limited number of pollen and phytolith samples will be processed after the summer 2004 field season to assess the quality of preservation. If the pilot project is successful, a new proposal will be submitted to complete the study.Current and future paleoenvironmental research in southwestern Guayas will contribute significantly to our understanding of the causes and consequences of agriculture. It will provide a case study of agricultural evolution in a lowland, dry tropical forest region that will be useful for scholars world-wide. Dry tropical forests, such as those that once characterized southwestern Guayas, are among the most endangered ecosystems in the New World because of the advantages they hold for modern agriculture. Evidence is accumulating that such habitats were also the focus of prehistoric agriculture, and home to many crop plants. Was agriculture sustainable in dry tropical forests prehistorically? The broader impacts of the study will be insights gained into the nature of human impact on forests through time, and practices that permitted populations to use these habitats for thousands of years. These findings may have application to the contemporary issue of sustainable uses of tropical forests.