The Climate Agreement set out that emissions from peatlands must be reduced by 1.0 Mton CO2 per year by 2030. The Dutch National Research Programme on Greenhouse Gases in Peatlands (NOBV) was launched in December 2019 to obtain more insight into current emissions as well as the effects that measures have on greenhouse gas emissions. The NOBV takes measurements of the impact of various measures – water infiltration systems, wet crops and soil modification – at different locations throughout the Dutch peatland areas.
The NOBV’s research results will be delivered in 2024. The first two measurement years were completed last autumn, and the first findings were set out in a data analysis report. An important observation after these first two years of measurement is that the functioning and effectiveness of measures is complex. The effects that measures have are dependent on specific conditions, meaning that results may vary from one region to another and from one year to the next. This in turn means that the current findings are preliminary; more years of measurement are required in order to draw conclusions. The initial findings can be divided into five main points:
- The effectiveness of measures depends on circumstances such as the weather, soil structure, permeability, seepage and runoff, and the way that the measure is implemented. The role and interaction of these conditions must be understood in order to better predict emissions and how effective measures will be.
- Raising the ditchwater level has the effect of reducing CO2 emissions. We also see that with a ditchwater level of between roughly 20cm and 50/60cm below ground level, underwater drainage results in further reduction.
- With wet crops and with high groundwater levels around ground level (this also applies to natural environments), methane emission can play a major role. Greater insight into the processes behind this emission should make the causes of the methane emission clear as well as the possibilities there are to reduce the emissions from this crop.
- Measurements and model results are still subject to uncertainties. Long-term measurements and further analysis of soil mechanisms in the soil are therefore required.
- The framework is in place for monitoring the progress of CO2-reducing measures in peatland. In the coming years, the uncertainties in the outcomes will be reduced further as more data is obtained.
Measurements at the existing sites will continue in the coming years and more measuring sites will be added. For example, measurement sites will be added at locations where the new measure, clay in peat, is implemented. Exploratory measurements will also be set up on various wet crops, such as peat moss, cranberry and miscanthus. This will increase understanding of the effects of these measures. Gathering more data will reduce the uncertainties more and more.
Click here to view the reports.
In response to these reports, the NOBV organised the webinar ‘Two Years of the NOBV: Where do we stand?’ which was held on 9 December 2021. To view a recording of the webinar, click here.
10 MARCH: SOMERS ONLINE QUESTION SESSION
The NOBV will hold an online question session about SOMERS from 9 to 10:30am on 10 March 2022. To sign up for this session, send an email to firstname.lastname@example.org.
The reduction in national CO2 emissions from peatland regions must be updated annually in order to assess whether the Climate Agreement reduction goals will actually be achieved. SOMERS (Subsurface Organic Matter Emission Registration System) was developed for this purpose. SOMERS enables CO2 emissions to be determined at plot level – both with and without measures in place. The system is currently in use for hydrological measures, such as ditchwater level adjustments, underwater drainage and pressure drainage. We provided information on this in a previous newsletter.
There are various calculation rules and models available for determining emissions from peat soils. These use, for example, process models, or empirical relationships between the emissions and an environmental variable. Both methods have their advantages and disadvantages. In order to monitor national emissions and the reduction in these when the measures are applied, it is important to do this in a way that is tailored as specifically as possible to the various different conditions in the peatland. It is clear that issues such as soil structure, drainage, weather, the seepage/runoff situation, the width of the plot and, for example, management/use, all influence the greenhouse gas emissions and a measure’s effectiveness. These variations can be taken into account when using a process model. SOMERS therefore uses different hydrological and carbon cycle process models. The process models can be improved as and when NOBV’s mechanistic understanding develops further. As measurement series become increasingly long, the uncertainties in the results get smaller and smaller
The current operational version of SOMERS is a 1.0 version, which yields reduction percentages that are roughly as reliable as, or slightly better than, existing models. The main advantage, however, is that the uncertainties can be quantified. In SOMERS 1.0, the expected reduction in CO2 emissions per ha per year (tons of CO2) was calculated for different ditchwater levels, ditch distances (width of plots) and peat soil archetypes. These reduction percentages from SOMERS 1.0 will be used when monitoring the reduction in emissions since 1 January 2017 through the measures that have been and will be taken. The SOMERS results will be tested against measurements made within the NOBV, although the measurement series are still short at this stage. As the NOBV continues, the model will be updated with the latest scientific insights and the measurement results.
The NOBV’s first findings were delivered last autumn and there was an online question session about SOMERS. To view this session, click here . A report on SOMERS will be delivered in February 2022, providing a more detailed explanation of the monitoring framework. The report will be published on the website in the second half of February. In the light of this report, we will hold a new online question session on 10 March 2022 from 9 to 10:30am. Are you interested in taking part? To sign up for this session, send an email to email@example.com.