Doctoral Dissertation Research: Land Use and Land Tenure in Prehispanic Tlaxcala

在Richard Lesure博士和Charles Frederick博士的指导下，Aleksander Borejsza将在墨西哥中部高地的特拉斯卡拉州为他的博士论文收集数据。他将对深思熟虑的农业梯田进行考古发掘，并检查受过去土地使用影响的冲积沉积序列。这些数据将被用来评估从第一个定居社区(约公元前850年)到殖民地早期(约公元前1650年)土地利用、土地保有权和社会结构之间的变化关系。特拉斯卡拉的大多数斜坡正在或曾经被梯田耕种。开垦和废弃的田地点缀着大片土地，土壤因侵蚀而被剥离。断断续续的溪流在深深根深蒂固的沟壑中流动，使得灌溉变得不可能。这种退化的景观是人类创造的，但其来源尚不清楚。在墨西哥的其他地区，土地退化被归咎于西班牙征服后的人口崩溃，以及耕种和放牧动物的引入。在特拉斯卡拉，由于两千年来原住民集约化农业的影响，这种情况变得复杂起来。史前聚落模式的变化表明，在那段时间里，不同的农业生态系统被反复创建、废弃和开垦。人类学家观察到，集约农业所需的投资将农民与土地捆绑在一起。离开土地得到改善的社区的成本增加，为新兴精英的社会剥削创造了机会。与此同时，通过建立农业生态系统来检查剥削的严重性，这些农业生态系统需要有积极性和熟练的小农进行密集管理，而他们的直接监督或替代对精英来说代价太高。对个人和世袭土地索取权的出现设定了条件。坡度梯田是这一过程的例证，既是集约化农业的手段，也是划定财产界限的手段。土地退化会减少可用农田的价值和数量，从而产生同样深远的社会后果。然而，在确定农业变化的区域顺序之前，无法知道过去获得的这种关系。Borejsza将朝着这个方向迈出一步，测定梯田系统的建立和废弃的时间，并将它们与土壤侵蚀和溪流挖坑现象联系起来。梯田采用的技术及其对产量的影响将通过挖掘和实验室分析进行评估。梯田的年代将通过测定梯田建设埋藏的土壤或挡土墙和填充物中的有机物、木炭和人工制品的年龄来确定。将对梯田下游的河谷进行勘测，以寻找暴露出冲积沉积物的河岸。在那里，沉积和土壤发展的循环将揭示斜坡侵蚀和稳定性的交替时期。这项研究将有助于辩论，美洲的地貌是如何接触到的，以及它的现代退化状况在多大程度上是不同环境中开发的技术的引入，因此不适合当地条件。它还将探讨在农业中成功引入特定创新和继续维持人工农业生态系统所必需的社会背景。

Under the direction of Drs. Richard Lesure and Charles Frederick, Aleksander Borejsza will collect data for his doctoral dissertation in the state of Tlaxcala, in the highlands of Central Mexico. He will conduct archaeological excavations of prehispanic agricultural terraces, and examine alluvial sedimentary sequences influenced by past land use. The data will be used to evaluate changing relationships between land use, land tenure and social structure, from the time of the first sedentary communities (ca. 850BC) to the early Colonial period (ca. AD1650).Most slopes in Tlaxcala are or have been terraced for cultivation. Cultivated and abandoned fields are interspersed with vast areas where the soil has been stripped away by erosion. Intermittent streams flow in deeply entrenched gullies, making irrigation impossible. This degraded landscape is a human creation, but its origin is unclear. In other parts of Mexico land degradation has been blamed on the population collapse that followed Spanish conquest, and the introduction of the plough and grazing animals. In Tlaxcala this picture is complicated by the effects of two millennia of intensive aboriginal agriculture. Changes in prehistoric settlement patterns suggest that different agro-ecosystems had repeatedly been created, abandoned and reclaimed in that time span.Anthropologists have observed that the investments required by intensive agriculture bind farmers to the land. The increased costs of leaving a community where land has been improved create opportunities for social exploitation by emerging elites. At the same time checks are imposed on the severity of exploitation, by creating agro-ecosystems that require intensive management by motivated and skilled smallholders, whose direct supervision or replacement is too costly for the elite. Conditions are set for the appearance of individual and hereditary claims to land. The terracing of slopes exemplifies this process, as the means of both intensifying agriculture and demarcating property. Episodes of land degradation can have equally far-reaching social consequences, by decreasing the value and amount of available farmland.Whether such relationships obtained in the past, however, cannot be known until firmly dated regional sequences of agricultural change are established. Borejsza will make a step in that direction by dating the construction and abandonment of terrace systems and relating them to the phenomena of soil erosion and stream entrenchment. The techniques employed in terracing and their influence on yields will be assessed through excavation and laboratory analysis. The age of terraces will be established by dating the organic matter, charcoal and artifacts in soils buried by terrace construction or included in the retaining walls and fill. River valleys downstream from terraces will be surveyed for cutbanks where alluvial deposits are exposed. There, cycles of sedimentation and soil development will reveal alternating episodes of slope erosion and stability.The research will contribute to the debate about how 'pristine' the landscape of the Americas was at contact, and to what extent its modern degraded condition is the effect of the introduction of technologies developed in different environments and therefore ill-adapted to local conditions. It will also explore the social context necessary for the successful introduction of particular innovations in agriculture and the continued maintenance of artificial agro-ecosystems.