Root carbon inputs outweigh litter in shaping grassland soil microbiomes and ecosystem multifunctionality

Area of Science:

• Soil science
• Ecology
• Microbiology

Background:

• Global change impacts soil carbon (C) inputs, affecting soil microbial communities and ecosystem functions.
• Semi-arid grasslands are sensitive ecosystems where changes in C inputs can have significant consequences.

Purpose of the Study:

• To investigate the effects of litter manipulation and plant removal on soil microbiomes and ecosystem multifunctionality (EMF) in a semi-arid grassland.
• To understand the role of above- and below-ground carbon inputs in maintaining soil health and ecological functions.

Main Methods:

• A 13-year field experiment involving litter addition, litter removal, and plant removal.
• Analysis of soil microbial alpha-diversity (bacterial and fungal).
• Assessment of microbial network stability and complexity.
• Evaluation of ecosystem multifunctionality (EMF).

Main Results:

• Litter addition did not affect soil microbial alpha-diversity.
• Litter removal reduced bacterial and fungal alpha-diversity due to decreased C substrate and soil moisture.
• Plant removal caused significant declines in microbial diversity, network stability, and complexity.
• Ecosystem multifunctionality (EMF) was enhanced by litter addition but reduced by plant removal, linked to fungal diversity loss.

Conclusions:

• Soil carbon inputs are crucial drivers of soil microbiome structure and function.
• Plant root-derived carbon is essential for maintaining soil microbial diversity and ecosystem multifunctionality in grasslands.
• These findings are critical for predicting and managing ecosystem responses to global change.