Fig. 2.
Vertical soil sections (20 cm deep, from the bottom of furrow) excavating and photographing scheme in ridge–furrow and plastic film fully mulched ridge–furrow cropping systems. (A) the rainwater catchment confine for one maize crop; (B) photographing the vertical soil section perpendicular to furrows (or crop lines); (C) photographing the vertical soil section (underneath the bottom of furrow) parallel to crop lines.