Innovations in Dryland Agriculture

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weed growth and saved labor; with this practice, the land needed no-tillage for three
to four years. The grain yield was also increased by 35–37 % (Han 2013 ) and 12 %
(Ma 2010 ) compared with conventional uncovered cultivation and film side planting
technology and film side planting technology, respectively, producing a significant
economic benefit than other farming methods.
Potato is one of dominant crops in the most dryland agricultural regions in China.
The water demand of potato during growth largely matches the distributions of rain-
fall and temperature in the season. Entering the twenty-first century, the area of
potato growing was quickly enlarged due to increasing demand of tubers in the
market. The plastic film mulched ridge-furrow technologies improved potato yield
by 20–50 %, even 100 % than non-mulched flat or ridge-furrow cultivation (Table
1 ) (Tian et al. 2003 ; Wang et al. 2005 ; Li 2011 ; Qin et al. 2014 ; Zhao et al. 2014 ).
In the potato production, black (opaque) plastic film had a better increasing effect
on yield than transparent plastic film (He et al. 2015 ). Removing off the film in the
middle of the growing season not only avoided the risk of plastic residue pollution,
but also maintained the same yield of 5280 kg ha−^1 , as was achieved from season
long mulching (Fan et al. 2012 ; Zhao et al. 2012 ).
Maize is a thermophilic crop with higher consumption of water and fertilizer. In
the past, farmers in dryland areas had little enthusiasm to plant maize. In recent ten
years, along with the increase demand of the global market and livestock feeding in
China, the price of maize continuously increased, almost up to the same level as
wheat. As a high-yielding crop, maize had more obvious advantages to produce
economic returns than wheat. The straw of maize can be used as forage and biogas,
and increasing soil fertility when applied back to the field. With so many advan-
tages, maize drew many attentions of the government, farmers and scientists.
Plastic film mulched ridge-furrow is currently a major cultivation pattern of
maize in dryland agriculture (Table 2 ). Big and small ridges are made and then
completely covered with transparent polyethylene film (Fig. 4 ). Maize is planted in

Table 1 Potato tuber yield of rainfall-harvest cultivation of ridge-furrow mulched with plastic
film

Site/Year Growth season

Rainfall

(mm)

Un-mulch

Flat (kg/ha)

Mulched

R-F(kg/ha) Sources

Gaolan/2001 April 29–Sept 5 162.1 995 D 3602 D Wang et al.

C Yuzhong/2002 April 29–Sept 5 181.6 671 D 2084 D (^2005 )

Dingxi/2009 April 30–Oct 8 245.5 2739 D 3993 D Zhao et al.

Dingxi/2010 April 25–Oct 5 243.0 2973 D 5288 D (^2012 )

Dingxi/2010 April 12–Sept

24

227.8 26,590 F 49,657 F Qin et al.

( 2014 )

Dingxi/2011 April 15–Sept

26

213.2 28,181 F 45,227 F

Note: D and F mean dry weight and fresh weight, respectively

Integrated Dryland Agriculture Sustainable Management in Northwest China