KEYLINK: towards a more integrative soil representation for inclusion in ecosystem scale models-II: model...

Area of Science:

• Soil science
• Ecology
• Biogeochemistry

Background:

• Soil structure significantly impacts hydrology and soil organic matter (SOM) stabilization.
• Existing models often overlook the intricate role of soil structure.
• Integrating soil structure with SOM dynamics and soil food webs is crucial for accurate predictions.

Purpose of the Study:

• To introduce the KEYLINK model, which integrates soil structure with SOM pools and soil food web dynamics.
• To provide equations and parameter intervals for model implementation.
• To demonstrate the model's capability in predicting soil carbon and water balances.

Main Methods:

• Development of the KEYLINK model, incorporating soil structure, SOM pools, and trophic interactions.
• Parameterization using Bayesian calibration with an example from a Belgian pine forest.
• Simulation of five test cases: altered litter quality, predator exclusion, pH changes, and altered soil porosity.

Main Results:

• The KEYLINK model successfully simulates known phenomena related to soil parameters.
• Demonstrated linked effects of biopore formation, hydrology, and aggregation on soil functioning.
• Revealed significant trophic cascade effects of predation on the carbon cycle and SOM turnover.

Conclusions:

• KEYLINK effectively simulates the interconnectedness of soil structure, hydrology, and carbon cycling.
• Trophic interactions play a critical role in soil carbon sequestration and emissions.
• Incorporating soil functional diversity and trophic organization is essential for improving soil carbon and water balance predictions.