Nonpoint Source Loading of Toxic Substances from Decomposing Crop Residue

摘要

Two adjacent, but separate watersheds were equipped to estimate total volume of runoff water and to collect an integrated water sample. One watershed was planted with corn (Zea mays) using no-tillage (NT) management and barley (Hordum vulgare) as a cover crop. The other watershed was planted with corn using conventional tillage (CT) management. Runoff water sampled between 1979 and 1983 were analyzed for phenolic acids and phytotoxicity to turnip (Brassica rapa). The volume of runoff water was reduced with NT management, but the concentration and total loading of phenolic acids were greater in runoff water from the NT watershed compared to that found in runoff water from the CT watershed.