• Koshiro Hayashi

The future of Agriculture


https://www.thai-german-cooperation.info/en_US/regenerative-rice-farming-in-thailand/


Agriculture and rice play a significant role in our diet, especially in our Asian community. For any delicious Thai food you think of such as Khao Pad and Pad Grapao, rice is a key ingredient. According to Statista, Thailand has now become the third-largest rice exporter in the world. As you can see, we are surrounded by rice and it is indispensable to our lifestyle. But, did you know that this essential crop is one of the largest sources of greenhouse gas emissions? Agriculture makes up around 10% of global greenhouse gas emissions and contributes to rapid global warming. Methane (CH4) and nitrous oxide (N2O) are the two major greenhouse gases that are produced from agricultural activities, such as the use of fertilizers and pesticides, waste management, and energy use. This summer (2021), I was able to be part of GIZ (Deutsche Gesellschaft für Internationale Zusammenarbeit) Thailand as a student intern for 3 weeks. GIZ is an organization that includes the concept of a government agency and a private firm. Its mission is to promote sustainability in developing countries and has a close connection with the sustainable development goals established by the United Nations.


Throughout this experience, I was exposed to various techniques and systems that promote social, economic, and environmental sustainability. I mainly contributed to the rice and agriculture area, but I explored various other fields including drug policy, climate change, and plastic pollution. Amongst all the fields I explored during my time at GIZ, “alternate wetting and drying” fascinated me the most. Alternate wetting and drying (AWD) is an agricultural technique that is used to reduce water consumption without impacting the total yield. In the AWD system, the paddy field alternates between a flooded and non-flooded state by adding irrigation water a certain day after the paddy field is dried up. This significantly reduces the water consumption for irrigation since farmers do not have to add water every day, as with the traditional method. This system can be implemented by using a “pani pipe”, a tube used to monitor the depth of water on a paddy field. It is often made of plastic or bamboo and contains numerous holes which allow the water to flow in and out. In standard conditions, the water depth will gradually decrease since water will be absorbed through evapotranspiration by vegetation and the atmosphere. Then farmers can easily check the water depth and apply irrigation when water depth has decreased to a certain level so it can be flooded again. This allows the farmer to consistently monitor the water depth and condition of the paddy field and reduce the total water consumption.


AWD can be used to reduce the methane emissions produced by agricultural practices. Rice and paddy fields produce 12% of global methane emissions, mainly caused by the anaerobic decomposition of organic matter. Most rice fields are flooded by water due to irrigation, which allows the water to block the oxygen from getting into the soil. This creates an ideal environment and condition for the methane-producing bacteria to survive. Thus, the longer the flooding condition and period of the rice field lasts, the more methane-emitting bacteria in the soil. However, AWD can prevent this condition since its system involves the non-flooded condition which is not an ideal environment for the bacteria. This can significantly reduce the amount of methane emissions without decreasing the yield.


AWD is one of the most fascinating agricultural inventions that humans have thought of. Although rice contributes a large proportion of global greenhouse gas emissions, AWD can be an ideal and convenient solution to reduce methane emissions for farmers who can’t afford technical agricultural equipment.


Thank you GIZ for all the support and for providing me with a fascinating opportunity in this difficult period.


References


M.Shahbandeh. “Largest Exporter of Rice Worldwide 2019 | Statista.” Statista, Statista, 22

Apr. 2021, www.statista.com/statistics/255947/top-rice-exporting-countries-worldwide-

2011/. Accessed 17 Nov. 2021.

R. M. Lampayan, et al. “Saving Water with Alternate Wetting Drying (AWD) - IRRI Rice

Knowledge Bank.” Www.knowledgebank.irri.org,

www.knowledgebank.irri.org/training/fact-sheets/water-management/saving-water-alter

nate-wetting-drying-awd. Accessed 17 Nov. 2021.

United States Environmental Protection Agency. “Sources of Greenhouse Gas

Emissions.” Epa.gov, 9 Oct. 2018, www.epa.gov/ghgemissions/sources-greenhouse-

gas-emissions. Accessed 17 Nov. 2021.