#ModellingMonday – CLUMondo in South Westphalia: Modelling land use under climate pressure

South Westphalia is an prime example of the challenges posed by climate-related land use. In this heavily forested region, heat, drought and bark beetles have already destroyed around 30% of the forests, especially spruce monocultures in the Arnsberg Forest. Soil drainage, soil compaction and a lack of diversity have severely weakened the resilience of the forests. 

 At the same time, the new „Wind Energy on Land Act“ is putting pressure on land use: two per cent of Germany’s land area is to be designated for wind energy. In South Westphalia, this applies to a great extend to calamity areas – formerly forested areas that are now in double demand: for climate protection through renewable energies and for reforestation for CO₂ storage and water regulation. How can the planned transformation succeed? 

CLUMondo: Modelling complex land use scenarios 

Can wind turbines (mitigation) and healthy forests (adaptation & mitigation) work in synergy? The South Westphalia region is investigating possibilities and contradictions in the KNOWING research project. 

The Horizon Europe project KNOWING is supporting the South Westphalia region in the course of this transformation with scientifically sound data and modelling. The land use model ‘CLUMondo’ model plays a central role in this process. CLUMondo was developed by Van Asselen & Verburg, P.H. at developed at Vrije Universiteit Amsterdam. It works with specific geographical locations and is scenario-based – it simulates land use changes based on defined drivers and objectives. For example, what would be the consequences of switching to drought-resistant tree species? Or the dismantling of historical drainage ditches in the Arnsberg Forest? CLUMondo is part of the CLUE family of models, is freely accessible and has been used in more than 180 studies worldwide.  

 Application in KNOWING: South Westphalia as a demonstrator 

 In KNOWING, South Westphalia acts as a demonstrator region for forestry and agricultural areas. CLUMondo can systematically simulate adaptation and mitigation measures and make conflicting interests tangible. The modelled measures in KNOWING include: 

• Reforestation with climate-resilient mixed tree species (permanent forest to strengthen biodiversity and CO₂ storage) 

• Sponge forest measures: Closing old drainage ditches, rewetting peatlands for water retention 

• Reduction of logging roads and forest roads to minimise soil compaction 

• Wind energy expansion on calamity areas, taking into account biodiversity loss and soil sealing 

The aim is to assess both the impact of individual measures and their interactions in the overall system. For example: Does the expansion of wind power lead to a justifiable deterioration of the water balance? Does renaturalisation sequester enough carbon to justify a loss of usable land? 

Role in the KNOWING system model 

 In KNOWING, CLUMondo is part of an overarching Impact Interaction Model Framework. In combination with other domain models (e.g. on energy, health or mobility), its results are incorporated into a system dynamics model that integrates, compares and evaluates climate-relevant target paths. The results of the simulation will form the basis for the region’s own SECAP. 

 Furthermore, the modelling in South Westphalia is also intended to serve as a basis for other regions with similar challenges. In KNOWING, these are the follower regions of Lauenburg (DE) and Tyrol (AT). They are given the possibility to assess and simulate different land-use scenarios to support sound decisions and interchange with conflicting goals.