3.4. Soil water content variation and soil water storage increase after
rainfall
We used the entire profile (0–70 cm) data from 2011 to 2012 to depict
temporal changes in soil water content (Fig. 8).
Soil water content variation among the four SM treatments was similar
throughout the 2-year period, except under BM. It fluctuated, with a
general decline from late July 2011 until middle April 2012. During this
time, which corresponds to the main growing season for white clover
and jujube, a larger quantity of soil water was required for growth.
Soil water content under BM continuously increased after that time,
and was far larger than that under other treatments. This is because a
full mulch cover of jujube branches can substantially decrease soil evaporation
and retain soil water. Additionally, we observed that the topsoil
under BM remained wetter during the whole experiment period. Soil
water content under BMWC from August 2011 to May 2012 was far
less than that under NC, often approaching the wilting point. Soil
water content continuously decreased until the first rainfall event in
2012, and then fluctuated with water input and output. We installed
micro-lysimeters in the soil bins in March 2013 to determine the soil