Abstract: Sandy soil (S), sandy loam soil (SL) and sandy clay loam soil (SCL) were transported using the spatial displacement method to Wuqiao Station of China Agricultural University, Hebei Province for studying soil moisture and crop yield under no-tillage with mulch and conventional tillage during 2010 to 2013. The results showed that compared with conventional tillage, no-tillage with mulch increased soil volumetric water content, and the effect was more obvious on SL than on S and SCL; the soil volumetric water content of 0-20 cm under no-tillage with mulch was lower than under conventional tillage in SCL, which is different from S and SL. However, crop water use efficiency (WUE) was not improved under no-tillage with mulch according to the first two years experiment. The variation trend of WUE was consistent for the three soils in wheat growing season. WUEs under no-tillage with mulch were 13.95%, 9.76% and 8.61% lower than under conventional tillage in S, SL and SCL, respectively. In maize growing season, differences in WUE were observed among different soil textures. WUE under no-tillage with mulch was 6.45% lower than under conventional tillage in S, while the WUE under no-tillage with mulch was 4.89% higher than under conventional tillage in SCL, but the differences were not significant. No-tillage with mulch did not show advantage in yield increase. The wheat yields were 7.09%, 4.26% and 0.39% lower under notillage with mulch than under conventional tillage, and the maize yield was 9.81%, 4.11% and 10.19% lower than under conventional tillage in S, SL and SCL, respectively. Under the experimental conditions, no-tillage with mulch has a better effect on water conservation, but cannot increase crop yield in short term.

Key words: three-dimensional fluorescence spectra, infrared spectroscopy, nitrogen deposition, soil solution, dissolved organic matter