Effect of straw incorporation on the temporal variations of water characteristics, water – use efficiency and maize biomass production in semi-arid China

Abstract

Field experiments were conducted in 2008–2010 in the Loess Plateau of China to study the effects of straw incorporation on maize growth and biomass water use efficiency (WUE) under semi-arid condition in dark loessial soil. Low (LS 4.5tha−1), medium (MS 9.0tha−1), and high (HS 13.5 tha−1) levels of straw were incorporated into the surface soil combined with fixed levels of inorganic fertilizers (CK) as control. Straw incorporation compared with CK significantly improved biomass yield at the tasseling–maturity stage of maize and WUE at the jointing–ten leaf collar and the tasseling–grain filling stages. WUEs with LS and MS treatments were significantly lower than that with CK at the ten leaf collar–tasseling stage, although the WUEs with MS and HS treatments were significantly higher in the whole growth period. HS treatment compared with LS treatment significantly increased biomass yield at the ten leaf collar–maturity stage and WUE at the jointing–tasseling stage. Meanwhile, MS and HS treatments compared with LS treatment significantly increased the biomass yield at the late grow period. Straw incorporation significantly improved WUE at the sowing–jointing stage and soil organic carbon relative to CK. Biomass yield at the ten leaf collar stage and WUE in whole growth period with LS treatment were significantly higher compared with CK. WUE at the ten leaf collar–tasseling and the grain filling–maturity stages were significantly higher with HS treatment compared with CK. In the long term, the rational straw incorporation level in improving maize biomass yield and WUE was 9.0tha−1.