This project is a collaborative effort by archaeologists and ecologists to investigate the legacy of prehistoric and modern human land use on the mesas of Agua Fria National Monument north of the Phoenix Basin. This desert grassland and riparian ecosystem has experienced two intense pulses of human use in the past 750 years: a sizeable agricultural occupation in the 1300s and livestock grazing since the mid 1800s. We are working to reconstruct key ecological and archaeological features of the landscape before, during, and after (in the case of the indigenous occupation) these pulses of human land-use. Our overarching questions are:

• How did 14th century economics, politics, and religious practices influence the ways in which people used the Agua Fria landscape?
• Which prehistoric activities left ecological legacies that are detectable on contemporary landscapes?
• Which ecological conditions make an ecosystem more or less prone to long-lasting human-induced disturbance?
• Can we still see effects of an increase in ecological patchiness we would expect in association with the 14th century occupation?
• How do legacies of prehistoric land use persist in the face of intensive grazing?

The goal of the project is to build theory about what types of human disturbances leave legacies over different time scales, and gain insights into the ways that today's actions can affect future ecological systems.

To begin addressing our research questions project personnel have spent two field seasons collecting a diversity of ecological and archaeological data. These data include the distribution of woody plants, small mammals, herbaceous plants, agaves, rocks, and artifacts at several survey locations. Additionally, the architectural growth of two prehistoric villages has been reconstructed through analyses of the wall alignments and the bonding and abutting patterns at the corners of rooms. Prehistoric agricultural fields have been located and several were selected for additional herbaceous plant surveys, soil analyses, and seed bank studies. At a landscape scale, one study has tracked woody plant expansion utilizing historic aerial photos and another developed a GIS model of potential prehistoric agricultural land. For links to reports and articles see http://legacies.asu.edu/publications.htm.

The Legacies project has a strong educational component, involving both graduate and undergraduate students in interdisciplinary research in the field and laboratory. Courses taught in 2004, 2005 and 2007 provided hands-on training in archaeological and ecological research and fieldwork that resulted in several graduate and undergraduate theses and professional papers.