3774.1.3 Conservation Agriculture
Conservation agriculture (CA) is gaining momentum as an alternative strategy to
sustain agricultural production due to the growing resource degradation problems,
particularly under dryland conditions. Sufficient information is available to indicate
that CA practices save time, reduce production costs and contribute substantially
towards profitability and sustainability of carbon in soils (Srinivasarao et al. 2013a).
However, in dryland ecosystems, having sufficient crop residue to leave on the sur-
face is not feasible as part of CA, nor is the conservation of first rains by deep tillage
before the rainy season to allow sufficient infiltration. Hence, typical CA with three
principles (minimum tillage/soil disturbance, permanent soil cover and crop
rotation/intercropping) needs to be investigated further to include in-situ water con-
servation of rainwater to recharge the soil profile. A modified CA with four princi-
ples for dryland agriculture is presented in Fig. 5.
4.1.4 Agricultural Intensification
The goal of agricultural intensification can be realized through the adoption of land-
saving technologies which enhance crop yields per unit area per unit time and unit
input of off-farm resources (Lal 2006 ). With available dryland technologies such as
rainwater management, crop options, short-duration varieties, and various agro-
nomical practices, more dryland areas can be used for intensive cropping including
relay cropping and double cropping. Double cropping is possible in areas with suf-
ficient rainfall (usually more than 750 mm) that have a soil storage capacity of more
than 150 mm of available soil moisture, or with rainwater harvested in farm ponds
which can be used to establish winter crops. There is plenty of scope for raising
farm outputs and income with diversification to high-value crops and by harnessing
niche areas particularly in mountainous regions. This will require markets for those
Fig. 4 Enhanced growth of Bt-cotton (left) with balanced nutrition compared to farmers’ practice
(right) in Adilabad and Khammam districts of Andhra Pradesh, India
Dryland Agriculture in South Asia: Experiences, Challenges and Opportunities