Chapter 2 : Role of Regenerative Agriculture in Combating Global Warming
October 13, 2021 at 09:12
Although no universally agreed-upon definition of regenerative agriculture exists, it generally promotes self-renewal and resiliency, contributes to soil health, increases water percolation and retention, enhances and conserves biodiversity, and sequesters carbon (Elevitch, 2018). Basic principles of regenerative agriculture generally include: "1) maintaining (to the degree possible) continuous vegetation cover on the soil, 2) reducing soil disturbance, 3) increasing the amount and diversity of organic residues returned to the soil, and 4) maximizing nutrient and water use efficiency by plants" (Paustian, 2020).
Soil carbon sequestration "has the potential to offset fossil-fuel emissions by 0.4 to 1.2 Gt C/year, or 5 to 15% of the global emissions," (Lal, 2004a) while providing enhanced food security at the same time. This is particularly true of undeveloped countries and regions, where agricultural production has not seen significant yield increases over the past 50 years. Therefore, regenerative agriculture's climate mitigation potential holds significant potential. (Paustian, 2020; Gosnell, 2020).
Regenerative agriculture can help mitigate climate change in two principal ways: by reducing the greenhouse gas emission of agricultural production, and through increased soil carbon sequestration. Compared to industrial agriculture, regenerative agriculture can significantly reduce the emission of greenhouse gasses, both direct and indirect. In addition, reclamation of devastated land, and better soil management of existing agricultural land provide additional carbon sequestration from the atmosphere, reducing the concentration of greenhouse gasses. Finally, better land management ensures that carbon emissions from the soil are reduced, because of prevention of erosion and reduced tillage.
Regenerative agriculture can minimize greenhouse gas emissions of agricultural production in several ways (Gosnell, 2020):Reducing or eliminating fossil-fuel derived inputs (like synthetic fertilizers, pesticides, and herbicides) (Picasso, 2014; Rotz, 2019) Reduced use of farming machinery and use of renewable energy sources (Lal, 2004b) Reduced need for off-farm inputs (Herrero, 2013; Dudley, 2014).
These reduce both the direct emission of greenhouse gasses through lower fuel and fossil-fuel energy consumption and the indirect emissions derived from the production of off-farm inputs like fertilizers and pesticides. It has been estimated that the net carbon footprint when utilizing regenerative agriculture methods is -628 to -3545 kg CO2-eq ha-1, compared to +488 kg CO2-eq ha-1 of conventional farming methods (He, 2019). This means that a switch from conventional to regenerative farming could effectively reduce emissions by 1.1 to 4 tons of CO2-equivalent per hectare annually.
Regenerative agriculture can also enhance the effectiveness and capacity of natural carbon sinks by reducing bare ground and soil erosion, planting perennial species, which develop larger and deeper root systems, and increasing plant productivity and microbial biomass (Xu, 2018; Henneman, 2014; McDermot, 2014; Badgery, 2014). Soil erosion has been estimated to be a significant contributor to anthropogenic greenhouse gas emissions, and regenerative agriculture methods can almost eliminate soil erosion while increasing soil carbon content (Teague, 2016). Healthier soil exhibits improved water retention, lowering water consumption of regenerative production. This has the side benefit of enhancing the resilience of regenerative fields to droughts and other natural disasters, reducing damage from them, and allowing regenerative fields to recover faster after adverse events (Bennett, 2021).
Coalition for Regenerative Agriculture
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