Degradation-driven vegetation-soil-microbe interactions alter microbial carbon use efficiency in Moso bamboo forests

Area of Science:

• Soil Science
• Microbiology
• Ecology

Background:

• Microbial carbon utilization efficiency (CUE) is key to soil carbon sequestration.
• Moso bamboo forest degradation impacts soil and vegetation carbon dynamics.
• The mechanism linking degradation, microbial CUE, and soil carbon sequestration is unclear.

Purpose of the Study:

• Investigate microbial CUE changes in degraded Moso bamboo forests.
• Identify biotic and abiotic factors controlling microbial CUE.
• Understand the role of microbial physiology in soil carbon dynamics.

Main Methods:

• Space-for-time substitution across four degradation stages (CK, DM1, DM2, DM3).
• Analysis of microbial CUE, biomass turnover time, soil properties, and microbial communities.
• Comparison of microbial CUE along a degradation gradient.

Main Results:

• Microbial CUE increased significantly with degradation (12.27% to 55.95%).
• Microbial biomass turnover time decreased, indicating faster microbial turnover.
• Enhanced microbial growth, driven by increased soil carbon substrates and altered microbial communities, was the primary driver of increased CUE.

Conclusions:

• Degradation of Moso bamboo forests enhances microbial CUE, primarily through promoting microbial growth.
• Increased vegetative carbon input replenishes soil carbon substrates, influencing microbial communities and physiology.
• Vegetation, microbial properties, and soil carbon substrates are critical for predicting microbial CUE in degraded ecosystems.