A Review of Environmental Impacts of Piggery Farming
Keywords:Environmental impacts, Piggery farming, Solid waste management
Piggery farming plays a significant role in the economy of different countries across the globe. Nonetheless, the rapid expansion of this industry raises concerns about its adverse environmental consequences. Therefore, the objective of this paper is to review the environmental impacts of piggery farming. The method used is the review of academic journals/articles, conference papers, internet materials, textbooks and publicly available materials on the environmental impacts of piggery farming. The results of the study indicated that previous authors whose works were reviewed had a convergent view that piggery farming has many adverse environmental impacts on land, water, air and human health as well as some beneficial impacts. The specific negative environmental impacts include (i) significant contribution to water pollution through the release of nutrients and pathogens from piggery solid waste; (ii) soil degradation by excessive application of piggery solid waste on land; (iii) emission of greenhouse gases—carbon dioxide (CO2), methane (NH4) and nitrous oxide (N2O); (iv) risk of the transmission of the zoonotic diseases from the pigs to animals and humans; and (v) emission of ammonia (NH3) from piggery farms which has severe adverse implications on biodiversity and human health. On the contrary, some of the beneficial impacts of piggery farming revealed by the review are (i) piggery solid waste is N-based manure useful in cropping activities to boost crop productivity; and (ii) improvement of livelihood and welfare of piggery farmers as well as a source of revenue to the government. The recommendations of this study include, among others: (i) the piggery sector should adopt sustainable practices to reduce the emission of greenhouse gases, collect methane as cooking gas and properly manage piggery solid waste; (ii) it is crucial that the appropriate authorities and the pig farm owners promote animal welfare and prevent the transmission of zoonotic diseases to ensure the safety of both animals and humans; and (iii) further researches are needed in this sector to explore its full beneficial impacts, develop innovative solutions and strategies to mitigate the adverse environmental impacts to ensure sustainable food security and economic growth.