The microbial feedback to soil warming: temperature dependences of growth, respiration and resulting carbon-use efficiencies

I will determine how soil microbial temperature relationships are shaped by their thermal environment.

A cross-continental survey of soils from different climates will be combined with experimentally warmed soils and within-system seasonal variation, to:determine temperature relationships for microbial growth, respiration, and carbon-use efficiencies in >60 ecosystems forming a wide climate gradient, and link these to site environmental characteristics and edaphic factors.verify the link to temperature regimen (from 1.) in field experiments.

Warming experiments will be assessed and seasonally resolved in subarctic, temperate, and subtropical ecosystems.

Temperature relationship variation due to climate (from 1.) will be compared to that due to seasons and experiments (from 2.), thus verifying the link between thermal regimen and microbial responses.analyze temperature effects on the community composition in 1-2.

Sets of taxa to use as biomarkers for warm-adapted communities will be established through linking sequence composition to temperature relationships.

By applying these to planet wide surveys of microbes we will infer the variation of temperature relationships globally.develop a mechanistic representation of microbial temperature relationships into a global-scale model.

We will represent dynamic microbial temperature relationships (from 1-3) and estimate how changes in temperature relationships will feed back to the soil-atmosphere exchange of C in IPCC scenarios.