121release fertilizers, and site-specific nutrient management options may also help
reduce the nutrient losses in the dryland crop production systems. In the following
lines, some pragmatic strategies for improving nutrient management in dryland
agriculture systems are discussed.
3.1 Conservation Agriculture
The conservation agriculture (CA) has been identified as an alternative to conven-
tional agriculture for sustaining the productivity of dryland regions through better
management of soil, water and nutrient resources. Reduction in soil losses and pro-
duction cost, and improvement in soil organic matter and plant available soil water
has been reported in various dryland regions, due to implementation of CA (Lyon
et al. 2004 ; Thomas et al. 2007 ). For example, in Ethiopia, long-term experiments
have demonstrated that CA may enhance the crop yield (Mesfin et al. 2005 ; Burayu
et al. 2006 ; Temesgen et al. 2009 ) by reducing the soil runoff and erosion (Oicha
et al. 2010 ) with substantial improvement in soil organic matter and soil mineral
nutrients (Burayu et al. 2006 ). In CA, surface mulch and legume cover improves the
storage of nutrients and water, which enhances the soil organic matter and thus
crops grown under CA requires less fertilizer (Lafond et al. 2008 ; Crabtree 2010 ;
Lindwall and Sonntag 2010 ).
Numerous other studies have reported yield improvement of 20–120 % due to
adoption of CA systems in dry Mediterranean climates than the traditional tillage
systems (Mrabet 2000 , 2002 ; Fernández-Ugalde et al. 2009 ; Fileccia 2009 ; Crabtree
2010 ; Piggin et al. 2011 ), due to improvement in soil moisture and nutrient avail-
ability. Indeed, after several years of adoption of CA, the soil has more amount of
biological N and has greater ability to release N than the tilled soil which help
enhancing the availability of nutrients to plants (Duiker and Beegle 2006 ; Lafond
et al. 2008 ; Crabtree 2010 ), and reducing runoff.
3.2 Fertilizer Application at Right Time, Through Right
Source, and at Right Place
For the best management of nutrition in dryland crops, the fertilizer should be
applied at right time, at right place, through right application method at appropriate
rate using the right source (Ryan and Sommer 2010 ). Janzen et al. ( 1999 ) opined
that sensible use of fertilizers in dryland agriculture, based on soil tests, proper
placement of fertilizer in the soil at or near the place of seeding can increase the
yield and quality of dryland crops owing to substantial reduction in nutrient losses
to the ground water and aerial environment.
Nutrient Management in Dryland Agriculture Systems