The soil depth determines soil multifunctionality via shaping the soil properties and microbial diversity

Area of Science:

• Soil Science
• Microbiology
• Ecology

Background:

• Soil microorganisms are crucial for subsurface ecological processes and biogeochemical cycling.
• The relationship between soil biodiversity and soil multifunctionality (SMF) is recognized, but the distinct roles of soil properties and microbial communities are not fully understood.

Purpose of the Study:

• To investigate the drivers of soil multifunctionality (SMF) in a subalpine grassland.
• To determine the relative contributions of soil properties and microbial community structure to SMF across soil depths.

Main Methods:

• High-throughput sequencing was used to analyze microbial communities.
• Soil samples were collected from the humus layer and down to 80 cm in natural soil profiles.
• Soil multifunctionality (SMF) and microbial diversity/network complexity were assessed.

Main Results:

• SMF, microbial diversity, and network complexity decreased with increasing soil depth.
• Soil properties, particularly pH and soil water content (SWC), were the main determinants of microbial community structure.
• Soil properties were the primary drivers of SMF, explaining a significant portion of its variance.
• Microbial diversity was a stronger predictor of SMF than network complexity.
• Bacterial diversity positively correlated with nutrient, carbon, and nitrogen multifunctionality, while fungal diversity did not.

Conclusions:

• Soil properties are the dominant regulators of soil multifunctionality (SMF).
• Microbial diversity, especially bacterial, plays a significant role in driving SMF.
• Understanding these relationships is key to elucidating the links between biodiversity and ecosystem functioning.