Carbon sequestration through urban ecosystem services: A case study from Finland

Area of Science:

• Environmental Science
• Urban Ecology
• Climate Change Mitigation

Background:

• Cities are expanding, reducing land for natural carbon sequestration.
• Plants absorb atmospheric CO2, while soils store it long-term.
• Urbanization challenges the capacity of green spaces to regulate atmospheric carbon.

Purpose of the Study:

• To assess how site efficiency in housing areas affects ecosystem services.
• To evaluate the role of carbon sinks (plants and soil) in mitigating greenhouse gas emissions.
• To analyze the impact of urban form on natural carbon regulation in Espoo, Finland.

Main Methods:

• Life-cycle greenhouse gas (GHG) emissions assessment for seven housing areas.
• Quantification of CO2 uptake by plant carbon sinks.
• Estimation of soil organic carbon accumulation.
• Comparison of ecosystem services across different housing densities.

Main Results:

• The contribution of carbon sinks to total emissions varied significantly, from 1.2% to 11.9%.
• Detached houses on large sites exhibited the highest carbon sequestration potential.
• Compact apartment blocks demonstrated the lowest potential for CO2 uptake and soil carbon storage.

Conclusions:

• Urban site efficiency critically influences the effectiveness of natural carbon sequestration.
• Significant knowledge gaps hinder precise quantification of ecosystem services in Nordic urban environments.
• Future research should focus on Nordic wood growth algorithms, cold-climate soil carbon factors, and garden maintenance scenarios.