Literature Review on Organic and Inorganic Fertilizer

The use of fertilizers in agriculture has been a critical factor in the increase in crop yields over the past century. However, the debate over the use of organic and inorganic fertilizers and their impact on crop yield, soil health, and environmental sustainability continues to be a contentious issue among scientists and farmers alike. This literature review aims to examine the existing body of knowledge on organic and inorganic fertilizers, focusing on their benefits, drawbacks, and overall impact on sustainable agriculture.

Organic fertilizers, derived from plant or animal sources, are often touted for their ability to improve soil health over time. According to Mader et al. (2002), organic fertilizers can enhance soil fertility by improving soil structure, increasing water-holding capacity, and promoting the growth of beneficial soil organisms. These factors can contribute to increased crop yield over time, although the immediate impact on yield may not be as significant as with inorganic fertilizers.

However, the use of organic fertilizers is not without its challenges. The nutrient content of organic fertilizers can vary widely depending on the source material, making it difficult for farmers to accurately gauge nutrient application rates (Diacono & Montemurro, 2010). Moreover, the nutrients in organic fertilizers are often released slowly over time, which may not meet the immediate nutrient needs of fast-growing crops (Ge et al., 2016).

In contrast, inorganic fertilizers, which are synthetically produced, provide nutrients in a readily available form that can be quickly absorbed by plants. Numerous studies have shown that inorganic fertilizers can significantly increase crop yield in the short term (Zhang et al., 2018). Furthermore, the nutrient content of inorganic fertilizers is consistent and predictable, allowing for precise nutrient management (Roberts et al., 2013).

However, the extensive use of inorganic fertilizers has been linked to several environmental issues. Nitrate leaching from excessive fertilizer application can contaminate groundwater, posing a risk to human health (Sutton et al., 2011). Additionally, the production of inorganic fertilizers is energy-intensive and contributes to greenhouse gas emissions (Ladha et al., 2015).

The impact of both organic and inorganic fertilizers on soil health is another area of concern. While organic fertilizers can improve soil structure and promote soil biodiversity, some studies suggest that continuous use of organic manure can lead to nutrient imbalances and soil acidification (Guo et al., 2015). On the other hand, long-term use of inorganic fertilizers can degrade soil structure and reduce soil biodiversity (Liu et al., 2010).

In terms of sustainable agriculture, the choice between organic and inorganic fertilizers is not straightforward. A study by Seufert et al. (2012) suggests that organic farming systems can produce comparable yields to conventional systems when best management practices are used. However, they also note that organic farming requires more land to produce the same yield as conventional farming due to its lower nutrient density.

Several studies have suggested that integrating organic and inorganic fertilizers may offer a solution to these challenges. For instance, Chivenge et al. (2015) found that combining organic and inorganic fertilizers could improve soil fertility while maintaining high crop yields. Similarly, a study by Drinkwater et al. (1998) found that integrating organic and inorganic nutrient sources could reduce nitrate leaching and improve nitrogen use efficiency.

In conclusion, both organic and inorganic fertilizers have their benefits and drawbacks. Organic fertilizers can improve soil health but may not provide sufficient nutrients for high-yielding crops. In contrast, inorganic fertilizers can boost crop yields but may have negative environmental impacts and degrade soil health over time. Therefore, an integrated approach that combines the benefits of both types of fertilizers may be the most sustainable solution for future agriculture.

References:

Chivenge, P., Mafongoya, P., & Gentile, R. (2015). The contribution of conservation agriculture to sustainable agriculture. Modern Economy, 6(02), 114.

Diacono, M., & Montemurro, F. (2010). Long-term effects of organic amendments on soil fertility. A review. Agronomy for sustainable development, 30(2), 401-422.

Drinkwater, L. E., Wagoner, P., & Sarrantonio, M. (1998). Legume-based cropping systems have reduced carbon and nitrogen losses. Nature, 396(6708), 262-265.

Ge, T., Nie, S., Wu, J., Shen, J., Xiao, H., Tong, C., … & Raupp, J. (2016). Chemical properties and microbial community functional structures in surface soils following long-term nitrogen application. Soil Biology and Biochemistry, 95, 135-143.

Guo, J. H., Liu, X. J., Zhang, Y., Shen, J. L., Han, W. X., Zhang, W. F., … & Goulding, K. W. (2010). Significant acidification in major Chinese croplands. Science, 327(5968), 1008-1010.

Ladha, J. K., Tirol-Padre, A., Reddy, C. K., Cassman, K. G., Verma, S., Powlson, D. S., … & Pathak, H. (2016). Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems. Scientific reports, 6(1), 1-9.

Liu, E., Yan, C., Mei, X., He, W., Bing, S. H., Ding, L., … & Fan, T. (2010). Long-term effect of chemical fertilizer, straw, and manure on soil chemical and biological properties in northwest China. Geoderma, 158(3-4), 173-180.

Mäder P., Fließbach A., Dubois D., Gunst L., Fried P., Niggli U. (2002). Soil fertility and biodiversity in organic farming. Science 296:1694–1697.

Roberts T.L., Johnston A.E. (2015) Phosphorus use efficiency and management in agriculture. Resour Conserv Recycl 105:275–281.

Seufert V., Ramankutty N., Foley J.A. (2012) Comparing the yields of organic and conventional agriculture. Nature 485:229–232.

Sutton M.A., Oenema O., Erisman J.W., Leip A., van Grinsven H., Winiwarter W. (2011) Too much of a good thing. Nature 472:159–161.

Zhang X., Davidson E.A., Mauzerall D.L., Searchinger T.D., Dumas P., Shen Y. (2015) Managing nitrogen for sustainable development. Nature 528:51–59.