Issues with Modern Agriculture

Agriculture is one of the most influential factors defining the prolific success of the human race. As Earth faces human overpopulation for the first time in history, agricultural sustainability is of the utmost importance as we attempt to feed a global population increase from 7.8 billion in 2020 to 9.9 billion by 2050 (Population Reference Bureau, 2020). Modern agricultural practices have been so successful that we are now able to cultivate and distribute large quantities of food all across the globe. This is a great human achievement, however, it is coming at a cost. Some of our modern agricultural practices such as soil tilling, monoculture, as well as the usage of chemical pesticides and fertilizers, do not have long-term soil health in mind. 

The tilling of soil is done primarily to oxygenate the soil and increase the rate of organic matter decomposition. This causes a greater influx of nutrients which are essential to plant life (AiZhen et al., 2009). For anthropogenic demands, this practice sounds promising but is overshadowed by the fact that tilling dramatically decreases organic matter levels long term and comprises soil structure, specifically the biopore network (see Figure 1) (Kladivko, 2001). Annual excessive tillage can be detrimental to soil fertility as it enhances erosion rates and reduces organic matter concentration, resulting in diminished yield, quality, and quantity of crop (Krauss et al., 2020).

Figure 1: The diagram above compares the soil structure resulting from intensive tillage versus long term no-till techniques. Intensive tillage displays a number of negative impacts such as compaction, the absence of biopore networks, and reduced concentration of organic matter. Long term no-till displays a much healthier network of biopores allowing for better root penetration and thus better growing conditions for agricultural topsoil. (Joel Gruver and Ontario Ministry of Agriculture, Food and Rural Affairs, 2008).

Monoculture, another major issue of modern agriculture, refers to cultivating a single crop in large numbers and close proximity. This practice causes increased susceptibility to disease and pests, nutrient depletion, as well as reduced microbial community structure (Zhao et al., 2018). Monoculture enhances the devastating capabilities of invasive pests and diseases which increases our dependence on chemical inputs like pesticides and fungicides (Magrach and Sanz, 2020). Additionally, monoculture places more stress on specific nutrients, causing a greater dependence on chemical fertilizers to maintain short-term soil productivity (Zhao et al., 2018). The preventative measures required to protect monoculture crops places a higher stress on resources to produce the same yield, resulting in more expensive produce. Additionally, large-scale destruction of crops can cause localized food insecurity for those living in poverty and without access to global produce.

Soil erosion is one of the most alarming issues threatening the health and vigour of our agricultural soils. Removing surface soils which contain the highest concentrations of organic matter, plant nutrients, and fine soil particles (Montgomery, 2007). Studies show that it takes approximately 300 years for one inch of agricultural topsoil to form. At our current rate of soil degradation, there is low feasibility in replacing lost soil content with soil that is equally productive (Joseph, 2008). 

With all this in mind, what does modern and sustainable agriculture look like and how can we protect these essential natural resources? In order to protect agricultural topsoil we must reduce destructive tilling as well as compaction, foster multi-culture crop rotation, reduce chemical usage, and practice better landscape and erosion management. In conjunction, these practices will ensure that our agriculture remains economically viable and environmentally sustainable.

References:

AiZhen, L., XueMing, Y., XiaoPing, Z., Yan, S., XiuHuan, S., RuQin, F. and HuaJun, F., 2009. Short-term impacts of no tillage on soil organic carbon associated with water-stable aggregates in black soil of Northeast China. Scientia Agricultura Sinica, [journal] 42(8), pp.2801–2808.

Joel Gruver and Ontario Ministry of Agriculture, Food and Rural Affairs, 2008. Best Management Practices: No-Till – Making It Work. [online] Available at: <http://www.omafra.gov.on.ca/english/environment/bmp/no-till.htm>.

Joseph, 2008. Environmental Studies 2E. 2nd ed. Tata McGraw-Hill Education.

Kladivko, E.J., 2001. Tillage systems and soil ecology. Soil and Tillage Research, [e-journal] 61(1), pp.61–76. https://doi.org/10.1016/S0167-1987(01)00179-9.

Krauss, M., Berner, A., Perrochet, F., Frei, R., Niggli, U. and Mäder, P., 2020. Enhanced soil quality with reduced tillage and solid manures in organic farming – a synthesis of 15 years. Scientific Reports, [journal] 10(1), p.4403. https://doi.org/10.1038/s41598-020-61320-8.

Magrach, A. and Sanz, M.J., 2020. Environmental and social consequences of the increase in the demand for ‘superfoods’ world-wide. People and Nature, [e-journal] 2(2), pp.267–278. https://doi.org/10.1002/pan3.10085.

Montgomery, D.R., 2007. Soil erosion and agricultural sustainability. Proceedings of the National Academy of Sciences, 104(33), pp.13268–13272. [e-journal] https://doi.org/10.1073/pnas.0611508104.

Population Reference Bureau, 2020. World Population Data Sheet. [online] Available at: <https://interactives.prb.org/2020-wpds/> [Accessed 21 Oct. 2021].

Zhao, Q., Xiong, W., Xing, Y., Sun, Y., Lin, X. and Dong, Y., 2018. Long-Term Coffee Monoculture Alters Soil Chemical Properties and Microbial Communities. Scientific Reports, [e-journal] 8(1), p.6116. https://doi.org/10.1038/s41598-018-24537-2.