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of new China, the government has taken large-scale actions to build terraces. The
terraces construction during the period from 1950s to 1970s had laid a strong base
for food security of newly established new China. When it came to the 1980s at the
beginning of the Policy of Reform and Opening Up, people’s enthusiasm of terrace
construction declined slightly. Yet in the 1990s, terrace construction revived once
again. Since entering the twenty-first century, the scale and speed of construction
were further accelerated. Efficiency and quality of terrace building have been greatly
improved by the application of machines (Xie et al. 2001 ; Wang 2006 ).
Numerous studies showed the effect of terraces on receiving the infiltration of
precipitation and increasing production (Ye 1984 ). In the hilly region of semi-arid
Loess Plateau, 92.4 % of rainfall in the summer effectively was trapped by terraces
and then infiltrated into soil system; the sediment loss was also greatly reduced cor-
respondingly. The soil water storage in the depth of 200 cm with terraces was 110–
180 mm more than that of slope farmland in a normal year. The water use efficiency
of crops in terraces built over 3 years was 1.01–3.38 kg/(mm hm^2 ) more than that of
farmland with a slope more than 10o (Yang 2006 ). In the semi-arid region of Ningxia,
compared to sloping farmland, terraces decreased soil bulk density in the depth of
0–100 cm, and increased the percentage of capillary porosity. During the period
from April to November, terraces increased the soil moisture in the depth of 0~100
cm, suggesting that terraces were more suitable for the infiltration and preservation
of rainfall, and maintaining high and stable yield. (Cai et al. 2007 ).
The major features of newly built terraces include low soil fertility, biological
activity and crop yields. To seek the ways to effectively improve soil fertility and
crop yield is an important issue. Many agricultural practices, including farming,
irrigation, film mulching, fertilizer application, and crop rotation system and others
could increase crop yield and water use efficiency (Ye 1984 ; Xie et al. 2001 ; Agbede
and Ojeniyi 2009 ; Behera and Panda 2009 ; Kunzová and Hejcman 2009 ). Among
all these measures mentioned above, fertilization was the most direct and effective
way to achieve higher crop production and maintain soil quality (Hong et al. 1998 ;
Xie et al. 2001 ; Bhattacharyya et al. 2007 ;). Our group had conducted a field
experiment in newly built terraces located in the region with an annual average
rainfall of 300 mm for seven consecutive years. It was found that crop yield and
water use efficiency with the mixed application of nitrogen and phosphorus fertil-
izer were significantly greater than those with the sole application of organic fertil-
izer and the control of no fertilizer application. Yet, with the year extending, the
magnitude of the increased yield by nitrogen and phosphorus fertilizer application
tended to decrease. In contrast, the effect of organic fertilizer application on yield
turned to have a significant increase (Fig. 1 ). After 4 years, the yields of peas and
spring wheat with organic fertilizer were higher than those of nitrogen and phospho-
rus fertilizer treatments (Fig. 3 ). Meanwhile, the amount of macro-aggregates par-
ticles (> 0.25 mm) with the application of organic fertilizer was significantly higher
than those of nitrogen and phosphorus fertilizer and no fertilizer control; the water
holding capacity of soil was also significantly improved. Thus, application of
organic fertilizer was the key measure to promote soil aging of newly built terraces
and sustainable increase of soil fertility and land productivity (Liu et al. 2013 ).
F.-M. Li et al.