Diminished soil functions occur under simulated climate change in a sup-alpine pasture, but heterotrophic temperature sensitivity indicates microbial resilience

• DOI: 10.1016/j.scitotenv.2013.12.071
• Publication Date: 2014-01-02T23:15:28Z
• Authors: Robert T.E. Mills; Konstantin S. Gav...; Thomas Spiegelberger; David Johnson; Alexandre Buttler
• Keywords: Resilience

The pressure of climate change is disproportionately high in mountainous regions, and small changes may push ecosystem processes beyond sensitivity thresholds, creating new dynamics carbon nutrient cycling. Given that the rate organic matter decomposition strongly dependent upon temperature soil moisture, respiration to both metrics highly relevant when considering soil–atmosphere feedbacks under a changing climate. To assess effects mountain pasture system, we transplanted turfs along an elevation gradient, monitored situ respiration, incubated collected top-soils determine legacy on sensitivity, analysed (SOM) detect quality quantity SOM fractions. In transplantation down-slope reduced moisture increased temperature, with concurrent reductions respiration. Soil acted as overriding constraint significantly temperature. Under controlled laboratory conditions, removal heterotrophic led significant respiration-temperature response. However, despite lower rates down-slope, response function was comparable among sites, therefore unaffected by antecedent conditions. We found shifts quality, especially light fraction, indicating recently deposited material. Our findings highlighted resilience microbial community severe climatic perturbations, but also stress during growing season can reduce addition direct plant productivity. This demonstrated subalpine pastures change, possible implications for sustainable use given turnover consequent