Soils from cold and snowy temperate deciduous forests release more nitrogen and phosphorus after soil freeze–thaw cycles than soils from warmer, snow-poor conditions

Effects of global warming are most pronounced in winter. A reduction in snow cover due to warmer atmospheric temperature in formerly cold ecosystems, however, could counteract an increase in soil temperature by reduction of insulation. Thus, soil freeze-thaw cycles (FTC) might increase in frequency and magnitude with warming, potentially leading to a disturbance of the soil biota and release of nutrients.

Here, we assessed how soil freeze-thaw magnitude and frequency affect short-term release of nutrients in temperate deciduous forest soils by conducting a three factorial gradient experiment with ex-situ soil samples in climate chambers. The fully-crossed experiment included soils from forests dominated by Fagus sylvatica (European beech) that originate from different winter climate (mean coldest month temperature range ΔT > 4 K), a range of FTC magnitudes from no (T = 4.0 °C) to strong (T = -11.3 °C) soil frost, and a range of FTC frequencies (f = 0–7). We hypothesized that highe...