Quantifying thermal adaptation of soil microbial respiration

Area of Science:

• Environmental Science
• Microbiology
• Climate Science

Background:

• Quantifying soil microbial respiration's thermal adaptation is crucial for understanding climate change.
• Methodological challenges and isolating microbial responses from carbon availability create uncertainty.

Purpose of the Study:

• To quantify the rate of thermal adaptation in soil microbial respiration.
• To assess the implications of this adaptation for soil carbon cycle feedbacks under climate warming.

Main Methods:

• Constructed temperature response curves for soil microbial respiration using soils from New Zealand.
• Utilized a natural geothermal gradient as a proxy for global warming.
• Estimated temperature optima and inflection points of respiration curves.

Main Results:

• Soil microbial respiration adapted to warming at a rate of 0.29°C ± 0.04 1SE for temperature optima and 0.27°C ± 0.05 1SE for inflection points per degree Celsius of warming.
• Observed that thermal adaptation lagged behind the rate of warming.
• Results support previous findings on the offset between thermal adaptation and warming.

Conclusions:

• Soil microbial thermal adaptation is demonstrably slower than climate warming.
• This offset has significant implications for predicting soil carbon loss or storage.
• Findings aid in quantifying the potential for both limitation and acceleration of soil carbon losses in a warming world.