Increased decomposer diversity accelerates and potentially stabilises litter decomposition

Area of Science:

• Ecology
• Soil Science
• Environmental Science

Background:

• Alpine ecosystems are highly sensitive to global change and land-use shifts.
• Understanding litter decomposition is crucial for predicting ecosystem responses to environmental changes.
• The role of decomposer diversity in alpine litter decomposition remains poorly understood.

Purpose of the Study:

• To investigate the impact of decomposer diversity on litter decomposition rates in alpine soils.
• To compare the effects of common alpine soil invertebrates (earthworms, millipedes, sciarid larvae) on decomposition.
• To assess the relationship between decomposer diversity and the stability of litter decomposition services.

Main Methods:

• A mesocosm experiment was designed to simulate alpine soil conditions.
• The study compared decomposition rates with single-species and multi-species (three-species) decomposer treatments.
• Litter mass loss was measured experimentally and estimated based on projected field decomposer biomass.

Main Results:

• Litter mass loss was 13-33% higher in the three-species decomposer treatment compared to single-species.
• Increased decomposer diversity significantly reduced the variability in decomposition rates.
• A portfolio effect was observed, where higher diversity stabilized decomposition.

Conclusions:

• Invertebrate decomposer diversity is critical for maintaining litter decomposition in alpine environments.
• Biodiversity plays a key role in ensuring the stability of ecosystem services in sensitive alpine regions.
• These findings are essential for predicting how alpine ecosystems will respond to ongoing environmental and land-use changes.