Innovations in Dryland Agriculture

116

Likewise, the productivity of various crops [sorghum (Sorghum bicolor (L.)
Moench), pigeonpea (Cajanus cajan (L.) Millspaugh)] in the dryland soils of semi-
arid tropics (India, East Africa, Australia, South America) is limited due to nutrient
poor soils in these regions. The potential of dryland soil to produce a good yield of
a specific crop is also limited due to widespread deficiency of micro and secondary
nutrients such as Zn, B, and sulphur (S), in addition to deficiency of macronutrients
and organic carbon (Rego et al. 2007 ; Sahrawat et al. 2007 ). The yield of various
crops in the dryland regions can be profitability enhanced with the management of
natural resources, the use of chemical fertilizers (IAEA 2005 ), and organic amend-
ments. This also helps in substantial reduction in soil and nutrient losses (Table 1 ).
In this chapter, the problems related to nutrient management in dryland agriculture
systems has been discussed, and strategies to improve the nutrient management and
crop productivity in the dryland soils are proposed.

2 Challenges to Nutrient Management in Dryland

Agriculture Systems

Crop production systems in drylands are confronted by several challenges including
water scarcity, weather variability, nutrient mining, low fertilizer use efficiency and
soil erosion. In the following lines, challenges related to nutrient management in
dryland systems has been described.

2.1 Monocropping and Nutrient Mining

In most of the dryland regions for the world, monocropping is quite common due to
insufficient availability of soil moisture at seeding time. Thus, the soil remains fal-
low for half period of time during the year which left the soil vulnerable to nutrient

Table 1 Impact of various soil amendments on reduction of runoff, soil loss, NO 3 -N and PO 4 -P
than control

Treatments

Runoff

(%)

Eroded soil

(%)

NO 3 -N

(%)

PO 4 -P

(%)

Control 0 0 0 0

Compost/manure + soil surfactant 22 72 55 72

Compost/animal or green manure + pigeon-pea

hedges + soil surfactant

28 71 75 81

Compost/animal or green manure + mulch +

pigeon-pea hedges

98 100 100 100

Source: Baptista et al. ( 2015 )

A. Nawaz and M. Farooq