Report on SOMERS 1.0

To determine whether the reduction target of 1 Mton from peat meadows as laid down in the Climate Agreement will actually be achieved in the long term, the national CO2 emission reduction in the peat meadow area must be recorded annually. The registration system SOMERS (Subsurface Organic Matter Emission Registration System) has been developed for this purpose. Calculation rules have been determined with SOMERS that can serve as indicative support in determining the effects of proposed measures on greenhouse gas emissions in the peat meadow area. The report on SOMERS 1.0 was delivered in December 2022. The report serves as a background document for the calculation rules. The monitoring philosophy and line of reasoning that led to the creation of SOMERS are also described. Finally, the report contains two technical appendices in which SOMERS’ underlying calculation models are explained. The report and appendices can be found here.


Final report Veen Innovation Program

Over the past two and a half years, the NOBV location in Assendelft has collaborated with the Veen Innovation Program (IPV). The IPV has conducted five years of research into other ways of land use in peat meadow areas. The IPV was completed in May 2022 and the IPV Final Report 2017-2022 was published. A final film about the Innovation Program has also been produced. The final report, film and more information can be found here.

Knowledge Exchange Venture with Wageningen University and TNO Research

The Knowledge Exchange Venture on 30 May 2022 focused on measurements with eddy covariance, nitrous oxide measurements, spatial variation, scaling up and aircraft measurements.

>> Click here to watch this Knowledge Exchange Venture

  • Bart Kruijt, researcher at WU in the field of climate change, carbon cycle, land-atmosphere interactions and the Amazon, discussed measuring the variation in CO2 and methane emissions with fixed and mobile eddy covariance;
  • Researcher Arnoud Frumau of TNO explained nitrous oxide measurements using eddy covariance and advanced equipment;
  • Ronald Hutjes, associate professor of land use-climate interactions at WU, zoomed in on integrating measurements between the plot and landscape scale with the aircraft measurements that WU performs within the NOBV.

This Knowledge Exchange Venture took place in collaboration with the National Soil Subsidence Knowledge Program (NKB), Wageningen University (WU) and TNO.

Calculation rules SOMERS

The reduction in national CO2 emissions in peatland areas must be monitored annually, in order to determine whether the Climate Agreement reduction target of 1 Mton from peatlands will actually be achieved in the long term. SOMERS (Subsurface Organic Matter Emission Registration System) has been developed for this purpose. With SOMERS, calculation rules have been determined that can act as an indicative support in determining the effects that proposed measures have on greenhouse gas emissions in peatland areas. They are estimates for ‘characteristic’ situations in three different regions of the Netherlands. The main objective of the models used to draw up these calculation rules is to monitor the reduction of greenhouse gas emissions, and therefore look at the peatland areas with controlled water levels throughout the whole of the Netherlands.

The calculation rules for the ‘characteristic’ situations in three different regions of the Netherlands and an explanation of the use of the calculation rules can be found here.

Initial NOBV findings

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.

Initial findings

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.

Further research

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.


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

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