THE CULTIVATION AND DECLINE OF HIGH-ALTITUDE WETLANDS IN THE EQUATORIAL ANDES

Soil sequences of the high-altitude wetlands of the Ecuadorian Andes provide evidence of indigenous human uses and the colossal eruption of Quilotoa (VEI 6) in 1280 AD. The eruption of Quilotoa marks the end of the warmer climate of the Medieval Climate Anomaly and the beginning of a cold dry period in the region, the initiation of the Little Ice Age. Samples from two wetland field systems at the archaeological sites of La Vega and Zuleta were collected for pollen, diatoms, phytoliths, particle size analysis, LOI, XRD, and XRF in conjunction with stratigraphic analyses to assess how these environments changed after the eruption. Evidence from within the remains of these wetland fields suggests that the wetlands may have already been disappearing before the first Europeans arrived in the region. Colonial documents often serve as one of the primary methods for reconstructing the environment and climate of the pre-Colonial Americas. Yet with the onset of the Little Ice Age in full swing at the time of arrival, the environment of the Americas documented by the European chroniclers was drastically different than that experienced by native inhabitants for most of the prior thousand years. Few places the Europeans encountered offered as much ecological diversity as what would become Ecuador where the distinct combination of latitude, altitude, and topography creates a variety of microenvironments. One unique environment described by the chroniclers was the high-altitude wetlands that formed in the Interandean Valley around the equator in northern Ecuador. Through the construction of raised ridges, selective clearing of vegetation, and cultivation of various species, the native inhabitants had transformed these wetlands into gardens capable of feeding hundreds of thousands where a variety of plants and animals were gathered. Colonial documents indicate that when the Spanish arrived, they drained many of these wetlands and appropriated the land for the grazing of cattle. The local populations were relocated to areas where European farming methods could be implemented to produce cash crops. Located in the heart of the Ecuadorian dairy industry and the site of the burgeoning rose industry, few if any of these wetlands exist today, but the transition to colonial rule may not have been the sole reason for their eventual disappearance.