Biomantle Formation and Site Preservation on Terraces of Low Order Streams in the Ozark Uplands

Abstract

Many terraces of low order streams in the Ozark uplands appear to have been stable since at least the early Holocene, indicated by strongly expressed soils with argillic horizons and early Holocene artifacts recovered from surface and shallow sub-surface contexts. These terraces hold sites that likely represent land use practices very different from those along better-studied large streams in the area. Artifact depth distribution curves show that a biomantle with accompanying stone zone has not formed under many of these terraces, despite their age. This contrasts markedly with much swifter rates of biomantle formation reported elsewhere. The lack of a fully formed biomantle in a soil of this age may be due to forces countervailing the downward movement of clasts through bioturbation, or slower rates of bioturbation overall.