Runoff and sediment yield from proxy records: Upper Animas Creek Basin, New Mexico - Introduction

Analyses of water- and sediment-yield records from the Walnut Gulch Experim ental Watershed, the San Simon Wash Basin, and the Jornada Experimental Ran ge, combined with observations of regional variations in climate, geology a nd soils, vegetation, topography, fire frequency, and land-use history, all ow estimates of present conditions of water and sediment discharges in the upper Animas Creek Basin, New Mexico. Further, the records are used to anti cipate fluxes of water and sediment should watershed conditions change. Res ults, intended principally for hydrologists, geomorphologists, and resource managers, suggest that discharges of water and sediment in the upper Anima s Creek Basin approximate those of historic, undisturbed conditions, and th at erosion rates may be generally lower than those of comparison watersheds . If conversion of grassland to shrubland occurs, sediment yields, due to a ccelerated upland gully erosion, may increase by 1 to 3 orders of magnitude . However, much of the released sediment would likely be deposited along An imas Creek, never leaving the upper Animas Creek Basin.