An expert believes the best we can do to help farmers is to “give them information so they can make immediate decisions in the short term”.

Maps pinpointing greenhouse gas emissions hotspots can help improve land management in countries preparing climate change mitigation strategies, a scientist has said.

Study:

Biodiversity “hotspots” more likely to have greater ecosystem co-benefits

“We want to improve accuracy of the estimates and establish a global standard for hotspots of greenhouse gas emissions,” said Mariana Rufino, a senior scientist with Climate Change Agriculture and Food Security (CCAFS) and the Center for International Forestry Research (CIFOR).

“Mitigation involves making decisions about how to slow or prevent climate change,” Rufino said, adding that hotspot maps will aid policymakers and contribute to international climate negotiations.

Rufino discussed her work ahead of U.N. climate talks in Warsaw, where the monitoring, verification and reporting of emissions is a major debating point in negotiations.

Q: What is the purpose of this research? 

A: In a general sense, everybody knows that cutting forests down is a problem and that livestock create emissions problems, and that rice emits methane, but these things are going to happen. We need livestock and rice and some of the forest is going to be lost, but what we need is to balance the relative gains and losses of doing one or the other.

Q: What techniques do you use to measure emissions?

A: Scientists take gas samples from the soil, analyse them using the appropriate lab equipment and convert those measurements into emissions to determine how many kilograms of CO₂ equivalent are emitted per square metre or per hectare. Many developing countries don’t have those numbers for land-based activities. What’s happening is that many, many countries in the world are using emissions estimates of their agricultural forestry activities based on external estimates — most are from the United States or Europe. What they’re therefore reporting as their estimated emissions is most likely far from what is real. That’s why scientists need to fill the research gap. A priority-setting exercise will help to decide where to start collecting data based on the relative importance of the greenhouse gas emissions and on the mitigation potential.

Q: What is the overall strategy? 

A: Our strategy is to include only land-based greenhouse gasGHG emissions. So the analysis will exclude human fossil-fuel use, and will map layers of soil, climate, vegetation, farming activities, losses due to soil degradation and combine them with emissions factors, to calculate the emissions. We’re focused on emissions caused by human activity. Because our program is also interested in food security and poverty reduction, the identification of future mitigation intervention will include the scope for increases in agricultural productivity. We have to do something quick for the poor in our society. We have to combine livestock forestry and wetlands maps, and we have to figure out how we put them together and where mitigation is feasible.

Q: What progress have you made so far?

A: We set the challenge for this research two years ago. Initially, we took a couple of sites, one in Kenya and one in the Philippines. We’ve since added three more areas. We started measuring emissions from landscapes — straight from landscapes. We characterized them by first looking at the land users. We knew farmers were using the land, but we needed to determine what sort of farmers, what sort of activities they were doing, what sort of crops and animals they were producing, and the levels of income they were achieving with these land-based activities.

After we understood how the land was being used, we developed a statistical design and selected some plots in the landscape and then we started measuring emissions — all gases: methane, nitrous oxide, carbon dioxide, and carbon stocks.

We also measured production and estimated the economics of all these production activities. We’ve been doing this for almost one year and we plan to continue, but this was expensive and intensive and required a large team. Therefore the need to target future research to sites where emissions are high, and mitigation is possible.

Q: How do we ensure mitigation efforts are reliable?

A: Mitigation options might not seem robust if they aren’t put in the context of climate variability. For example, one year they might look as though they are working really well and another year they might look like a big failure — it’s just part of the overall variability entrenched in natural or biological systems and associated with climate change.

Q: How could these maps help smallholder farmers?  

A: In terms of climate variability, the best we can do to help farmers is to give them information so they can make immediate decisions in the short term. These might include, for example, whether or not to plant maize, or whether it would be better to grow sorghum — or to plant nothing if the risk is that the crop and any financial investment will be lost. When they can manage their own information they can make adaptation decisions.

The maps detailing hotspots of greenhouse gas emissions can help countries to prioritise mitigation interventions, which can benefit farmers if financing mechanisms become available for them. Financing mechanisms for mitigation can certainly seek for synergies with adaptation. Therefore, the hotspot analysis will include climate variability to assess the the robustness of the mitigation interventions.

Q: How can farmers balance adaptation and mitigation?

For mitigation-related decisions, farmers make choices that take into account climate change. For example, farmers decide how fertilizers should be applied to get the maximum amount of grain. If they’re made aware that just by changing the technique they can reduce emissions by half, well, why not adopt such a technique? That’s a mitigation decision in the short term that can be an adaptation decision in the long term. There is evidence that fertility management make sense to adapt to a changing climate. So this is an example of mitigation and adaptation working together to improve livelihoods.

Q: What does the future hold for GHG emissions mapping?

These estimates are needed everywhere in the world — I am convinced of that. Sooner or later this needs to happen everywhere. Compensation mechanisms will be needed to implement mitigation options. If there’s a country with large areas of peatlands or wetlands — I’m talking about a huge amount of tons of carbon emitted — then a mitigation mechanism will have to compensate for affecting economic development in that area and conserving carbon-rich ecosystems.

For further information on the topics discussed in this article, please contact Mariana Rufino at m.rufino@cgiar.org.

This work forms part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).