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

在美国国家科学基金会的支持下，Deborah M. Pearsall及其同事将开展一项试点项目，研究史前厄瓜多尔沿海地区的玉米，以及农业社会出现和发展过程中环境和社会因素的相互作用。该项目将利用环境核心法，研究与农业出现有关的植被、土地利用做法和生计的变化。西南沿海的瓜亚斯省被认为是棉花、利马豆、南瓜和豇豆的驯化中心，也是辣椒、椰子树、勒兰、竹芋、美人蕉和甘薯的发源地之一。这些作物大多出现在前陶瓷期（9800-6700 BP）和早期形成期（5500-3500 BP）。有证据表明，玉米是在前陶瓷时代晚期引进的，并出现在早期形成的Real Alto遗址，构成了这种作物在南美洲最早的日期之一。然而，根据现有数据，很难评估玉米在形成性生计中的重要性，以及它在沿海复杂社会的出现中所起的作用。从渔业采集社会向农业社会转变的过程对当地环境产生了重大影响。为了通过人类对环境影响的“窗口”，全面检验有关农业的因果的假设，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。Pearsall和他的同事们将尝试通过在瓜亚斯省西南部的三个有早期考古遗址的地点进行震动测量，从泻湖环境中检索这些记录。将对岩心沉积物取样进行花粉、植物岩（植物蛋白石二氧化硅）和沉积分析，并去除有机物质进行碳-14定年。在2004年夏季野外季节之后，将对有限数量的花粉和植物岩样品进行处理，以评估保存的质量。如果试点项目成功，将提交一份新的提案来完成研究。瓜亚斯西南部当前和未来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、干燥的热带森林地区农业演变的案例研究，这将对全世界的学者有用。干燥的热带森林，如曾经以瓜亚群岛西南部为特征的热带森林，是新世界最濒危的生态系统之一，因为它们对现代农业具有优势。越来越多的证据表明，这些栖息地也是史前农业的中心，也是许多农作物的家园。在史前干燥的热带森林里，农业是可持续的吗？这项研究的更广泛影响将是深入了解人类对森林影响的本质，以及允许人类使用这些栖息地数千年的做法。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.