干旱区生态环境知识资源中心

Dust in its myriad forms impacts human existence in arid environments; but dust is more than an environmental nuisance. It shapes and reshapes adaptive response and human ideology over the short and long term. In 2011, the Gila River Indian Community (GRIC), Arizona, U.S.A. sponsored a study of dust entrainment within the jurisdiction of its airshed. The study’s primary objectives were to determine the relationship between sediment sources and sinks in premodern contexts and how indigenous people have coped with eolian activity since intensive settlement of the Middle Gila River Valley began. Ethnographic and archaeological sources indicate that people respect winds and observe cultural procedures consistent with their origin and to reduce their ill effects. Geomorphic data also show stratigraphic correspondence between relic wash channels and adjacent terrace and sand sheet deposits demonstrating a long history of eolian activity derived from fluvial sources. Climatological data from PM10 "exceedance events" corroborate anthropological analyses indicating that extreme dust events are typically westerlies and occur during exceptionally dry periods. Eolian dust is part of the ambient ecosystem of the GRIC and should be viewed as such within the modern cultural and regulatory environment governing these emissions.