In my last post, I gave a quick overview of how chemical fertilisers can have both positive and negative impacts on nature and humans. For today, we will delve deeper into the widespread use of nitrogen fertilisers in global agriculture by reviewing this article published in the October 2019 issue of Geographical.
In the article, Burton (2019, p. 10) explains that these nitrogen-based fertilisers are responsible for feeding nearly half of the world’s population, and remain crucial for ensuring global food security. At the same time, she also acknowledges the devastating consequences of air and water pollution in cases where they are used excessively. The article also mentions that a research team from the University of California, Davis is currently proposing a holistic approach that can help re-distribute the global supply of nitrogen fertilisers, so that they become accessible to farmers who truly require them. As a result, the wastage of nitrogen fertilisers and its subsequent negative impacts can be avoided.
From the above, it is clear that nitrogen fertilisers are a double-edged sword whose effects are highly dependent on exposure. The regulated and restrained use of nitrogen fertilisers can indeed ensure that farmers enjoy a bountiful annual harvest and fulfil the global demand for food. On the contrary, the wastage caused by overuse poses as a danger to the surrounding environment and even the crops themselves, as demonstrated in a study performed on lettuce exposed to nitrogen fertilisers during growth. According to Liu et al. (2014, p. 4427), the level of nitrate in lettuce increased as larger amounts of nitrogen fertiliser were used, hence suggesting the possible dangers of nitrate contamination among these types of leafy vegetables. As such, the reduced use of nitrogen fertilisers to a level that is reasonable for sustainable farming can aid in ensuring both food safety and security. This would therefore be an example of a more effective management of nitrogen fertilisers as a resource.
At the same time, I wish to point out that the proposed approach is in fact a sophisticated process that needs to climb over many hurdles. For instance, how can we determine the distribution of nitrogen fertilisers to farmers? Even if we were to allocate the fertilisers to farmers based on field size, there may be large-scale farms which are less efficient in producing higher yields as compared to medium-scale farms, but this fact remains overlooked due to the algorithm used to determine how much fertiliser they can obtain and use. Perhaps the re-distribution can focus on less-developed farming areas which show promise in being able to cater to local demand, so as to boost their self-sufficiency and reduce the need for them to import these crops from another region. This may also complement the aforementioned holistic approach, which speaks of the need to minimise food waste and encourage dietary changes, in order to reduce the world’s reliance on nitrogen fertilisers.
Overall, although I feel that the use of nitrogen (as well as phosphorus) fertilisers in large-scale commercial farms is justified due to the key role they play in increasing the yield, it is also important to use only what is needed for the crops and environment to remain healthy. It would be good for farmers with access to labs and monitoring equipment to experiment and find out the optimal amount of fertiliser to be used for the specific types of crops they grow, before sharing the information with others who may be interested in health and the environment!
Best wishes,
Jialing
Reference List
Burton, K. (2019) ‘The Nitrogen Dilemma’, Geographical, 15 October, pp. 10-11. Available at: https://geographical.co.uk/nature/climate/item/3382-the-nitrogen-dilemma (Accessed: 28 August 2020).
Liu, C., Yu, S., Chen, B., and Lai, H. (2014) ‘Effects of Nitrogen Fertilizers on the Growth and Nitrate Content of Lettuce (Lactuca sativa L.)’, International Journal of Environmental Research and Public Health, 11(4), pp. 4427-4440. doi: 10.3390/ijerph110404427.