TY - JOUR T1 - Reasearch reports JF - Journal of Soil and Water Conservation SP - 257 LP - 260 VL - 47 IS - 3 AU - G. W. Langdale AU - W. C. Mills AU - A. W. Thomas Y1 - 1992/05/01 UR - http://www.jswconline.org/content/47/3/257.abstract N2 - Water erosion on Typic Hapludult soils of the Southern Piedmont may exceed the soil loss tolerance (T)value because of a few low-return-frequency storms. A 19-year watershed data set was used to determine the erosion retarding effect of double-cropped conservation tillage systems on 11 low-return-frequency storms. These large storms, exceeding 100 mm of rainfall or an erosion index of 1,000 MJ mm(ha-h)−1, occurred between June 1972 and June 1991. Intensive conservation tillage management improved soil carbon, water stable aggregates, and rainfall retention. Runoff plot data collected and used in part for the development of the universal soil loss equation model during a previous 20-year hydrologic period (1940–1959) also authenticates the occurrence of low-return-frequency storms and their accelerated erosive effects following conventional tillage. Conservation tillage technologies were essential to successfully inhibit destructive soil erosion resulting from low-return-frequency storms occurring on the Southern Piedmont. ER -