Asia - Bangladesh, India, Pakistan Issue
Climate change is leading to increased temperatures and rainfall variability in South Asia. Rising temperatures are expected to lead to lower yields of one or more major crops (wheat, rice, and maize) in all countries of South Asia, while increased rainfall variability is expected to reduce average yields of rice and/or wheat in the drier parts of Bangladesh, India, and Pakistan (Aryal et al., 2020).
Solution
Agricultural practices and technologies that can reduce water use can help farmers adapt to increasing temperatures and rainfall variability, which is likely to result in more frequent or severe drought conditions. Based on a systematic literature review, Aryal et al. (2020) identified several practices and technologies that have been successfully used in South Asia. These included alternate wetting and drying (an irrigation practice), micro-irrigation systems (an irrigation technology), and laser land leveling (a technology allowing for more efficient irrigation).
Short Summary:
Climate change (rising temperatures and rainfall variability) is causing increased water stress in South Asia, which is significantly affecting smallholder farmers in the region. Several water management practices can help these farmers become more resilient to water stress, including alternate wetting and drying, use of micro-irrigation (or other water-saving) irrigation systems, and laser land leveling (Aryal et al., 2020). Institutional frameworks and funding sources for implementing these solutions need to be enhanced, however, to allow them to be scaled up throughout countries in the region.
Description (Details)
Introduction
The average farm size in South Asia is only around 0.5 hectares, which poses great challenges to large-scale implementation of new agricultural management practices in the region. Many of these small farms are being impacted by climate change, however, and would benefit from climate change adaptation measures that can increase the resilience of major crops. Aryal et al. (2020) conducted a systematic literature review to identify adaptation options for smallholder farmers in South Asia. Several of the adaptation options identified are related to climate-resilient water management strategies, and are described in more detail here.
Alternate wetting and drying
Alternate wetting and drying is an irrigation practice for rice paddies. Unlike traditional rice paddies, which are continuously flooded, alternate wetting and drying involves flooding the paddies, and then allowing the soil to dry until cracks appear on the soil surface or the crop shows symptoms of water shortage (Ye et al., 2013). This saves a significant amount of water used for irrigation, and can help farmers cope with droughts.
Micro-irrigation
Micro-irrigation systems employ small sprinklers or surface/sub-surface drips to deliver water directly to crops. Because they only provide water where it is most needed, micro-irrigation systems can save significant amounts of water, e.g., 12- 84% in India, depending on the crop type (Aryal et al., 2020). Although this technology can reduce water needed for irrigation, there are doubts over the potential for water conservation at the national or regional level, as it could instead lead to further expansion of crop production in dry regions, where the limiting factor for agricultural expansion is groundwater for irrigation (Kumar, 2016). Thus, suitable water management policies are also needed to ensure the resilience of agriculture during droughts.
Laser land leveling
Laser land leveling involves the use of a machine with a laser system and land leveler to create an extremely flat agricultural field (https://ccafs.cgiar.org/news/laser-land-levelling-how-it-strikes-all-right-climate-smart-chords). In South Asia, laser land leveling has been found to save significant amounts of water needed for irrigation in rice, wheat, and sugarcane croplands, and also to lead to increased yields of these crops (Jat et al., 2015).
DISCOVER MORE
