Interest in agricultural practices peaked around 1961, a time period which was eventually known as the Green Revolution. Currently, we are living during a time when a variety of methods are being sought to limit climate change, and agricultural practices also need to be considered as they also release greenhouse gases, which are the drivers for anthropogenic climate change. Such practices need to be improved in order to limit the amount of greenhouse gases that are released into the atmosphere. Burney et al. (2010) have considered three agricultural development scenarios. One (RW) is based on the real world situation, the second (AW1)is such that it is focused on land expansion and finally, the third one (AW2)is characterized by increased yield. The final recommendation was that if agricultural practices are carried out so that there is emphasis on the quantity of output rather than the quantity of input, there will be lower greenhouse gas emissions and thus making the third scenario (AW2) the most beneficial for the climate. – Nitya Chhiber
Burney, J.A.,Davis, S.J.,Lobell,D.B.,2010. Greenhouse gas mitigation by agricultural intensification. PNAS 107, 12052–12057.
Burney and his colleagues at Stanford wanted to understand the best combination of factors for ensuring the least minimal impact of agricultural practices on climate. They did this by describing three scenarios: one (RW) was based on the real world situation, the second (AW1) is characterized by an emphasis on land expansion and finally, the third (AW2) is characterized by yield gains. The last scenario was the control, which was used to compare with the former two scenarios. What must be noted that as certain parameters were difficult to be measured quantitatively, they were converted to other units; for example, yield was measured using monetary values in the form of global spending on yield investment. The timescale that was considered vis-à-vis yield improvements was between the years of 1961 and 2005. Furthermore, other parameters that contributed to yield improvement were not considered, such as fertilizer and irrigation. Finally, in order to ensure the existence of a fair test for more accurate results, the two scenarios (AW1 and AW2) had to be characterized by the same parameters and therefore, pesticides; fuel use and transport were not considered. Graphs were drawn depicting the amount of gigatons of gas emissions, namely pertaining to the gases of nitrogen dioxide, methane, carbon and finally, carbon dioxide, released that corresponded with the amount of yield improvement.
It was found out that the least impact on climate was when there was focus on outputs, for example, increased yields that resulted from an increase in efficiency of fertilizer usage rather than focusing on increasing inputs, such as in the form of expansion of land. It was also found that the AW2 scenario constituted of an overall lower amount of greenhouse emissions. This is not because AW2 was marked by yield improvements but because AW2 maintained 1961 standards of living and thus was characterized by an overall lower pressure on land by the population. Therefore, the existence of land expansion, also known as extensification was lessened in this particular scenario.