Chemical Fertilizer in Agriculture: A big source of Greenhouse Gas Emissions
In the present day, human behaviour is leading to one of the world’s biggest issues. We are producing a huge amount of greenhouse gases. The atmosphere contains many types of greenhouse gases. The major greenhouse gases are carbon dioxide, methane, nitrous oxide and industrial gases. Greenhouse gases trap heat from the sun inside the earth’s atmosphere making the earth warmer, causing climate change. This affects the environment, wildlife and human health. The major human activities that release greenhouse gases are agriculture, transportation and industry.
Greenhouse gas emission from Agriculture and Land use
Our lives are run by livestock and food produced from the agriculture sector. It has been shown that agriculture contributes to 15% of global greenhouse emissions. Agriculture emits all three gases, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Methane traps heat at a rate 25 times higher than carbon dioxide while nitrous oxide traps heat 298 times higher than carbon dioxide. With this highest potential trapping of nitrous oxide, it is important to focus on the source of nitrogen (N) released in agriculture. The main source of nitrogen in agriculture are organic and inorganic fertilizers, which are important for growing crops. Although it generates direct and indirect emission for greenhouse effect, we can not stop using fertilizer as it is the nutrient source for plants.
Figure 1: Evolution of net GHG emissions from 1990 to 2019. agriculture also emits Methane (44% of anthropogenic emissions) and Nitrous oxide (80% of anthropogenic emissions)
Current fertilizer practices in Thailand
Chemical fertilizers are used widely among sugarcane farmers in Thailand due to its lower cost of production and sufficient nutrients. However, most farmers lack knowledge about how to use chemical fertilizer in an effective way. The solution to do this is, optimizing the proportion and type of fertilizer used to reduce the cost and pollution caused by fertilizer. To know the optimal portion for fertilizer applied, the knowledge of the soil’s chemical properties is necessary. Chemical properties in the soil are indicators for nutrients, ion exchange capacity, acid-base condition and amount of organisms living in the soil. Soil analysis is a useful method but it is difficult for farmers to do that because they have to send the sample to an analysis centre. Another alternative way is growing nitrogen fixing plants like beans and legumes to increase nitrogen in the soil. Currently, there is an attempt to encourage farmers to apply chemical fertilizer in specific portions (N-P-K) from location to location as the soil’s quality and needs of the plant are different depending on geographical location. If the farmers apply excess chemical fertilizer, the chemical can sustain in the plants. It can be transformed into a new compound as a carcinogenic substance when entering the human’s body which can cause cancer afterward. Therefore, it is beneficial when the farmers follow the recommended portion of fertilizer use and have a good impact on the environment and human’s life.
Fairagora Asia’s Project
In 2021, Fairagora Asia is launching the Smallholders Impact Project which mainly focuses on environmental impact and social aspects in sugarcane farming in Thailand. Many activities in sugarcane cultivation create greenhouse gas emissions, for example, sugarcane burning, fertilizer use, fossil fuel and irrigation. Chemical fertilizer is playing a big role for N2O production. A huge amount of N2O is produced by nitrogen in the soil by applying excess fertilizer. In this project, we are using technology to create a solution. VerifiK8 is the technological tool used to monitor all data in the farm. We implement the mitigation activities to reduce greenhouse gas emission related to fertilizer use, e.g. optimize the amount use of organic and chemical fertilizer, water system and soil analysis. We will monitor the data yearly to see the improvement of carbon footprint and other environmental impacts.