The Bangladesh Centre for Advanced Studies (BCAS) and the International Food Policy Research Institute (IFPRI), with the support of the United States Agency for International Development (USAID), held a final workshop on Low Emissions Development Strategies (LEDS) for the agriculture, forestry, and land use change (AFOLU) sectors at the BRAC Inn Centre in Dhaka, Bangladesh, on September 25 and 26. The workshop brought together more than 60 experts in their fields to discuss ways to reduce greenhouse gas (GHG) emissions without seriously hurting agricultural production.
Attendees of LEDS AFOLU workshop in Dhaka.
One of the features of the event was putting together 4 working groups that covered soils and crops; livestock and fisheries; forestry; and biofuels and cookstoves. Each expert chose the working group that best suited their area of expertise. Each of these working groups developed concrete policies in their particular focus topic that could be implemented to deliver “smart mitigation” — reduction of GHG emissions per unit of output without hurting overall production.
The graph at right shows one way to think about GHG emission efficiency, which I call “smarter mitigation”. You see from the graph that the emissions to yield ratio falls and fertilizer inputs rise. In this example (which is not based on real data), increasing nitrogen fertilizer improves yields while increasing emissions, but the ratio falls, meaning that over the range of fertilizer uses shown, it makes sense, from the point of view of emissions, to use the maximum amount of fertilizer.
In the example at left, even though the slopes of the lines for yield change and emissions change are the same as in the previous example, emissions per unit of output rises with fertilizer increases, which makes any use of fertilizer inefficient from the perspective of GHG emissions.
What we have not included in the calculation is economic efficiency. Fertilizer costs money, so it may not make sense to even use any fertilizer if it is too expensive. OR, fertilizer maybe very cheap relative to the yield gains, so it may be very profitable to use a lot of fertilizer, despite its impact on GHG emissions. All of these are empirical questions which can be answered by data on emissions and yield responses to fertilizer, along with farmgate prices of rice (or whatever crop is being considered) and fertilizer.
In order for “smarter mitigation” to be considered genuinely “smart mitigation”, it also has to make economic sense — that is, not only does the emissions per unit of output need to fall, but the level of fertilizer chosen needs to make good economic sense, bringing better economic returns per unit of fertilizer or per unit of land.
In cases where the optimal fertilizer level for the best GHG emissions per unit of output is greater than the optimal fertilizer level in economic terms (i.e., profit), there could be justification for subsidies on the fertilizer or the crop to give incentives to the farmer to increase production and lower emissions per unit of output. This could also serve national food self-sufficiency and household food security objectives.