Fig. 1. Relationships between soil total C and clay + silt content at the 0- to 5-cm depth based on combined data from four plots for each treatment fitted with two-segment linear regressions in (a) conventional tillage with conventional chemical inputs (CT), (b) conventional tillage with leguminous cover crops and no chemical inputs (CT-cover), and (c) no-till with conventional chemical inputs (NT) treatments. The dash lines indicate locations of optimal break points from two-segment regressions.