Chapter Three - Climate Change and Agriculture: Adaptation Strategies and Mitigation Opportunities for Food Security in South Asia and Latin America

During the past two centuries, the world has witnessed a remarkable increase in the
atmospheric concentrations of the greenhouse gases (GHGs), namely carbon dioxide
(CO2), methane (CH4), and nitrous oxide (N2O), as a result of human activities after 1750
(preindustrial era). During 1750 the concentrations for these gases were 280 ppm, 715
ppb, and 270 ppb, respectively which increased to 379 ppm, 1774 ppb, and 319 ppb,
respectively in 2005. It showed an increase of 0.23, 0.96, and 0.12% annually. The same
has further increased to 385 ppm, 1797 ppb, and 322 ppb, respectively in 2008
representing 1.6, 1.2, and 0.9% increase, respectively from 2005 levels at an annual
increase of 0.53, 0.43, and 0.31%, annually. Increase in atmospheric CO2 promotes
growth and productivity of plants with C3 photosynthetic pathway but the increase in
temperature, on the other hand, can reduce crop duration, increase crop respiration
rates, affect the survival and distribution of pest populations, and may hasten nutrient
mineralization in soils, decrease fertilizer-use efficiency, and increase evapotranspiration.
The water resources which are already scarce may come under enhanced stress.
Thus, the impact of climate change is likely to have a significant influence on agriculture
and eventually on the food security and livelihoods of large sections of the urban
and rural populations globally. The developing countries, particularly in South Asia and
Latin America, with diverse agroclimatic regions, challenging geographies, growing
economies, diverse agricultural production systems, and farm typologies are more
vulnerable to the effect of climate change due to heavy dependence on agriculture for
livelihood. These regions also are demonstrating poor coping mechanisms to adapt to
these challenges, and as a result there is evidence of negative impacts on productivity
of wheat, rice, and other crops to varying extent depending on agroecologies.
Upscaling of modern technologies such as conservation and climate smart agriculture,
judicious utilization of available water for agriculture through microirrigation and
water saving technologies, developing multiple stress-tolerant crop cultivars and
biotypes through biotechnological tools, restoration of degraded soils and waters, use, and conservation of biodiversity must be promoted at regional and country level
to ensure durable food and nutritional security. Reliable early warning system of
environmental changes, their spatial and temporal magnitude, coupled with policies
to support the diffusion of this information, can help interpret these forecasts in terms
of their agronomic and economic implications for the benefit of farmers and to
provide agriculture-dependent industries and policymakers with more informed
options to support farmers. These countries need to formulate both short-term
and long-term policies for improvement, sustenance, and protection of natural
resources. There is an urgent need for capacity building through international collaboration
in order to develop databases and analysis systems for efficient weather
forecasting as well as preparing contingency plans for vulnerable areas. The objectives
of this paper are to summarize the available information on adaptation strategies and
the mitigation options for climate change to meet the food security in South Asia
and Latin America.