Climate Change Adaptation - Climate Resilient Agriculture for Ensuring Food Security - page 229

particularly in the transition phase, until the new
balance of weed populations is established. The
practice of conservation may also lead to soil com-
paction over time; however, this can be prevented
with chisel ploughs or sub-soilers. Initial invest-
ment of time and money along with purchases of
equipment and herbicides will be necessary for
establishing the system. Higher levels of surface
residue may result in higher plant disease and pest
infestations, if not managed properly. There is a
strong relationship between this technology and
appropriate soil characteristics. This is detrimental
in high clay content and compact soils.

adopting RCTs, which minimize unfavorable
environmental impacts, especially in small- and
medium-scale farms. Resource-conserving
practices like zero-tillage (ZT) can allow farmers
to sow wheat sooner after rice harvest, so the
crop heads and fi lls the grain before the onset of
pre-monsoon hot weather. As the average tem-
peratures in the region rise, early sowing will
become even more important for wheat. Field
results have shown that the RCTs are increas-
ingly being adopted by farmers in the rice-wheat
belt of the Indo-Gangetic Plains because of
several advantages of labor saving, water saving,
and early planting of wheat. These approaches of
crop management should be coupled with the
measures of crop improvement for wider adapta-
tion to climate change. Soil and water manage-
ment is highly critical for adaptation to climate
change. With higher temperatures and changing
precipitation patterns, water will further become
a scarce resource. Serious attempts towards water
conservation, water harvesting improvement in
irrigation accessibility, and water-use effi ciency
will become essential for crop production and
livelihood management. Farmers have to be
trained and motivated for adopting on-farm water
conservation techniques, micro-irrigation sys-
tems for better water-use effi ciency, selection of
appropriate crops, etc. Principles of increasing
water infi ltration include improvement in soil
aggregation; decreasing runoff with use of con-
tours, ridges, vegetative hedges, etc.; and reduc-
ing soil evaporation with use of crop residues
mulch for better management of soil water.

12.2.5 Adjusting Cropping Season

Adjustment of planting dates to minimize the
effect of temperature increase-induced spikelet
sterility can be used to reduce yield instability, by
avoiding having the fl owering period to coincide
with the hottest period. Adaptation measures to
reduce the negative effects of increased climatic
variability as normally experienced in arid and
semiarid tropics may include changing of the
cropping calendar to take advantage of the wet
period and to avoid extreme weather events (e.g.,
typhoons and storms) during the growing season.
Cropping systems may have to be changed to
include growing of suitable cultivars (to counter-
act compression of crop development), increas-
ing crop intensities (i.e., the number of successive
crop produced per unit area per year), or planting
different types of crops. Farmers will have to
adapt to changing hydrological regimes by
changing crops.

12.2.7 Crop Diversifi cation

12.2.6 Effi cient Use of Resources

Crop diversifi cation, which can be defi ned as
increasing the number of crops or the varieties
and hybrids of a particular crop, is a potential
farm-level response to climatic variability and
change (Bradshaw et al. 2005 ). Crop diversifi ca-
tion in a subsistence farming system provides an
alternative means of income generation for small-
holder farmers, the majority of whom are vulner-
able to climate change. Because of changing
rainfall patterns and water resource depletion,

The resource-conserving technologies (RCTs)
encompass practices that enhance resource- or
input-use effi ciency and provide immediate,
identifi able, and demonstrable economic benefi ts
such as reduction in production costs; savings in
water, fuel, and labor requirements; and timely
establishment of crops, resulting in improved
yields. Yields of wheat in heat- and water-stressed