Doctoral Dissertation Improvement Grant: Water-Level Fluctuations and Ancient Maya Wetland Management and Settlement in the Yalahau Region of the Northern Maya Lowlands

玛雅低地人类/环境相互作用的研究是评估气候变化的人类维度的全球努力的前沿。超过二十年的研究已经说明了玛雅工程和农业对环境的影响。最近，对湖心沉积物、同位素和化石的研究表明，气候引起的环境变化（如干旱）与玛雅地区的文化变化之间存在联系。环境变化可能对玛雅历史产生重大影响的一个地区是墨西哥金塔纳罗奥州北部的亚拉豪地区。雅拉豪地区人类生态项目的考古调查记录了密集的玛雅人定居点，以及玛雅人操纵当地湿地条件生产食物的证据。据信，雅拉豪玛雅人在公元前100年至公元350年至400年间的一次占领浪潮中，首先在湿地建造了他们的城镇并在此工作，然后放弃了这一地区，直到近900年后才返回。有趣的是，雅拉豪地区被遗弃发生在古典时期，这是邻近的玛雅王国繁荣的时期。越来越多的证据表明，墨西哥湾和加勒比海的海平面变化，以及尤卡坦半岛北部降水模式的变化，跨越了人类在雅拉豪地区定居的时间，这表明雅拉豪玛雅人可能在环境变化影响湿地的生产活动时放弃了该地区。在本研究中，我们提出了过去海平面和降雨模式的变化引起了地下水位的波动，从而导致了雅拉豪地区湿地及其相关生态群落的扩张、收缩和/或侧向迁移。我们进一步提出这些环境变化影响了人类在湿地的生存生产，并可能解释雅拉豪地区不同寻常的定居历史。在Scott L. Fedick博士的指导下，Lance Wollwage将重建lagunas（池塘）和cenotes（天然井或天坑）的环境记录，以研究过去3000年来Yalahau地区环境变化的时间和性质以及人类的反应。收集到的环境变化数据也有可能提供全新世相当一部分时期的古气候记录。雅拉豪湿地的沉积物可能保存着一个经典时期的气候记录，它只受到古典玛雅农业破坏的最小影响。对玛雅低地的人类定居、农业发展、“经典时期崩溃”和其他生态问题感兴趣的考古学家，以及来自其他学科的环境科学家，将会发现感兴趣的数据。该项目的古环境推断将为了解玛雅低地全新世自然史、史前文化和长期人类/环境相互作用提供基础。

Studies of human/environment interactions in the Maya Lowlands are at the forefront of global efforts to assess the human dimensions of climate change. Over two decades of study have illustrated the environmental consequences of Maya engineering and agriculture. Most recently, studies examining sediments, isotopes and fossils from lake cores suggest links between climate-induced environmental changes like droughts, and cultural changes in the Maya region. One area where environmental change may have significantly affected Maya history is in the Yalahau region of northern Quintana Roo, Mexico. Archaeological investigations by the Yalahau Regional Human Ecology Project documented dense Maya settlements, and evidence that the Maya manipulated conditions in local wetlands for food production. It is believed that the Yalahau Maya first built their towns and worked the wetlands during a surge of occupation sometime between 100 B.C. and A.D. 350/400, then abandoned the region before returning nearly 900 years later. Interestingly, abandonment of the Yalahau region occurs during the Classic period, a time of prosperity in much of the neighboring Maya realm. Mounting evidence of sea level shifts in the Gulf of Mexico and Caribbean Sea, and changes in precipitation patterns across the northern Yucatan spanning the time of human settlement in theYalahau region presents the possibility that the Yalahau Maya abandoned the area when environmental changes impacted productive activity in the wetlands.In this study we propose that past changes in sea levels and rainfall patterns caused fluctuations in the water table, which caused expansion, contraction and/or lateral migration of wetland and associated ecological communities in the Yalahau region. We further propose these environmental changes impacted human subsistence production in the wetlands, and may explain the unusual settlement history in the Yalahau region. Under the supervision of Dr. Scott L. Fedick, Lance Wollwage will reconstruct environmental records from lagunas (ponds) and cenotes (natural wells or sinkholes) to examine the timing and nature of environmental changes, and human responses in Yalahau region over the last 3,000 years. It is also possible that the data collected on environmental changes will provide a paleoclimatic record for a considerable part of the Holocene. Sediments from the Yalahau wetlands may hold a Classic period climate record that is only minimally affected by the ravages of Classic Maya farming. Archaeologists interested in human settlement, the development of agriculture, the "Classic Period Collapse", and other ecological issues in the Maya Lowlands, as well as environmental scientists from other disciplines will find the data of interest. Paleoenvironmental inferences from this project will provide a basis for understanding Holocene natural history, cultural prehistory, and long-term human/environment interactions in the Maya Lowlands.