Cover crops and tillage effects on carbon–nitrogen pools: A lysimeter study

Cover crops (CCs) and tillage practices influence C N pools in soil, which can affect dissolved organic (DOC) leaching from agricultural fields. Previous studies on cover have focused mostly nitrate total (TC). Therefore, a study was conducted southern Illinois 2015 to 2018 evaluate the effects of systems (conventional till [CT] no-tillage [NT]) CCs including water-extractable (WEC), permanganate oxidizable (POXC), TC, (WEN), (TN) soil TN DOC collected with zero-tension lysimeters. Crop rotations included were corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation without winter CC (C–S), corn–cereal rye (Secale cereale L.)–soybean–hairy vetch (Vicia villosa Roth) (C–R–S–HV), rye–soybean–oat + radish (Avena sativa L.+ Raphanus sativus L.) (C–R–S–OR). The WEC decreased over time under CT system at depth 0–15 cm C–R–S–OR having cereal oat CCs. POXC depths 15–30 30–45 increased significantly fall spring for all both systems. cumulative greater C–R–S–HV than C–S 2018. Inclusion reduced compared no Increased losses introduction should be addressed need further evaluation its impact cycling surface subsurface waters.