Human Ecology of the Rio Verde Drainage Basin, Oaxaca, Mexico

在国家科学基金会的支持下，亚瑟·乔伊斯博士和他的合作者将在墨西哥瓦哈卡州的里约维德流域进行一个考古和古生态研究的野外季节。这条河的上游分水岭位于瓦哈卡高地，发源于见证了蒙特阿尔班崛起的山谷，蒙特阿尔班是中美洲史前最大、最复杂的州之一。在其下游，里约维德河穿过沿海平原，流入太平洋。在之前对低地地区的研究中，乔伊斯博士指出，与墨西哥太平洋沿岸的许多其他地区相比，公元前500年以前的居住地极其稀少。公元前500年以后，人口密度和土地利用程度急剧增加。乔伊斯博士对这一现象提出了一种环境解释。他注意到，就在低地扩张之前，有一段明显的高地侵蚀严重时期，他认为这是由于森林砍伐造成的，因为蓬勃发展的高地群体清除了大片地区的农业生产。他认为，上游的沉积物被沉积到下游，从而提高了沿海平原的肥力。这反过来又促进了低地人口密度的增加。尽管考古学家和古生态学家多年来一直认识到，史前中美洲农业对环境产生了重大的负面影响，但里约热内卢的这一案例特别令人感兴趣，因为它具有广泛的区域规模，而且高地退化可能在较低的海拔地区产生相反的影响。该地区为人类环境相互作用的复杂性提供了一个很好的案例研究。乔伊斯博士和他的同事们将进行协调一致的环境和考古研究。在里约维德河源头，考古顺序是众所周知的，该小组将把重点放在收集地质和生态数据上。他们将检查河流切割，以构建一个地质序列。他们还将采集花粉来监测植被的变化。有了这些数据，应该可以重建侵蚀的时间和顺序，并确定气候和人为诱导因素的相对输入。在沿海地区，研究既包括考古内容，也包括环境内容。通过一系列岩心，将研究土壤的形成并重建古海岸线。考古表面调查与聚落挖掘相结合，将提供对人口规模和社会复杂性随时间的变化的洞察。这项研究具有重要意义，因为它为史前人类与环境的相互作用提供了一个很好的案例研究。在美国中部，人口增长和复杂性增加(和减少)的时间因地区而异，乔伊斯博士的研究应该会为潜在原因提供洞察。

With National Science Foundation support Dr. Arthur Joyce and his collaborators will conduct one field season of archaeological and paleoecological research in the Rio Verde drainage in the state of Oaxaca, Mexico. The upper watershed of the river is situated in the Oaxaca highlands and derive from valleys which witnessed the rise of Monte Alban, one of the largest and most complex prehistoric Mesoamerican states. In its lower reaches the Rio Verde crosses the coastal plain and empties into the Pacific Ocean. In prior research in the lowland region, Dr. Joyce has noted that before 500 B.C. habitation is extremely scarce in contrast to many other areas along the Pacific coast of Mexico. After 500 B.C. population density and degree of land utilization increase dramatically. Dr. Joyce has suggested an environmental explanation for this phenomenon. He has noted an apparent period of heavy upland erosion just prior to the lowland expansion and believes it was caused by deforestation as burgeoning highland groups cleared extensive areas for agricultural production. Upstream sediments were deposited, he believes, downstream thereby increasing the fertility of the coastal plain. This in turn fostered an increase in lowland population density. Although archaeologists and paleoecologists have recognized for many years that prehistoric Mesoamerican agriculture had major negative environmental impacts, this Rio Verde case is particularly interesting because of its broad regional scale and the possibility that upland degradation had just the opposite effect at lower altitudes. The region provides an excellent case study into the complexity of human environment interaction. Dr. Joyce and his colleagues will conduct coordinated environmental and archaeological studies. In the Rio Verde headwaters the archaeological sequence is well known and the team will focus on the collection of geological and ecological data. They will examine river cuts to construct a geological sequence. They will also collect pollen to monitor vegetation change. With these data it should be possible to reconstruct erosional timing and sequence and determine the relative inputs of climatically and humanly induced factors. In the coastal area the research includes both archaeological and environmental components. Through a series of cores, soil formation will be studied and paloecoastline reconstructed. Archaeological surface survey combined with settlement excavation will provide insight into the changes in population size and social complexity over time. This research is important because it with provide an excellent case study in prehistoric human-environmental interaction. The timing of population growth and increase (and decrease) in complexity varies from region to region in Middle America and Dr. Joyce's research should provide insight into potential causes.