Abatement costs of climate-friendly peatland management – Case study results for two German peatland regions under agricultural use

CONTEXT

In Germany, peatlands drained for agriculture cause more than 40 Mio. t CO₂ equiv. per year, which accounts for 44 % of all agricultural emissions. Because of their high mitigation potential, they are becoming increasingly important for EU agricultural policy and Germany's national mitigation efforts.

OBJECTIVE

Our work investigates how farms can adapt when they either extensify their drained grasslands with raised water levels (wet use) or abandon conventional land use under full rewetting. We also calculate income changes and abatement costs of adaptation strategies.

METHODS

To simulate successive land use conversions, we applied a linear programming farm-level model. The data are based on interviews with managers of typical farms in two German peatland regions with very different agricultural structures: the first, the Eider-Treene-Sorge lowlands in Schleswig-Holstein, with farms (Ø 150 ha) that are predominantly grassland based, and the second, the Rhin-Havelluch in Brandenburg, with mainly large (Ø 2000 ha) mixed farms. The farms represent a gradient of intensively, moderately and extensively used grassland. In addition, we carried out grassland monitoring to estimate forage quality at different water levels and intensities of grassland use.

RESULTS AND CONCLUSIONS

The results show the farm-level effects of increasing land use conversion on the grasslands of the six model farms. This includes the loss of fodder quantity and quality and its consequences, such as a reduction in cattle stock. The main adaptation strategies are intensification of the remaining grassland and increased feeding of arable forage. The associated marginal farm income losses are expressed in shadow price curves that vary greatly. They depend on farm structural variables (farm type, adaptation potential) and are sometimes very steep, especially in semi-intensive farms, i. e. for a large proportion of the grassland, income losses are low (up to 500 €/ha) while the last hectares incur exceptionally high losses (several thousand euros). The corresponding marginal greenhouse gas abatement costs also exhibit a wide range but are mainly below 55 €/t CO₂ equiv. The findings further show that extensive wet use causes higher abatement costs than full rewetting.

SIGNIFICANCE

Patterns of the shadow price and abatement cost curves are transferable to comparable farms. Findings indicate adequate compensation rates for different farm types and can be used to limit the impact on the affected farms, e. g. avoidance of high income losses by land consolidation.