| Spohn, M; Chodak, M: Microbial respiration per unit biomass increases with carbon-to-nutrient ratios in forest soils, Soil Biology & Biochemistry, 81, 128-133 (2015), doi:10.1016/j.soilbio.2014.11.008 | |
| Abstract: The ratio of carbon-to-nutrient in forest floors is usually much higher than the ratio of carbon-to-nutrient that soil microorganisms require for their nutrition. In order to understand how this mismatch affects carbon (C) cycling, we investigated the respiration rate per unit soil microbial biomass – the metabolic quotient (qCO2) – in relation to the soil carbon-to-nitrogen (C:N) and carbon-to-phosphorus (C:P) ratio in temperate forests. For this purpose, cores of beech, spruce, and mixed spruce-beech forest soils were cut into slices of 1 cm from the litter layer down to 5 cm in the mineral soil, and the relationship between the qCO2 and the soil C:N and the soil C:P ratio was analyzed. We found that the qCO2 was positively correlated with soil C:N ratio in spruce soils (R = 0.72), and with the soil C:P ratio in beech (R = 0.93), spruce (R = 0.80) and mixed forest soils (R = 0.96). We also observed a close correlation between the qCO2 and the soil C concentration in all three forest types. Yet, the qCO2 decreased less with depth than the C concentration in all three forest types, suggesting that the change in qCO2 is not only controlled by the soil C concentration. We conclude that microorganisms increase their respiration rate per unit biomass with increasing soil C:P ratio and C concentration, which adjusts the substrate to their nutritional demands in terms of stoichiometry. |
Upcoming ...
Upcoming ...
| BayCEER Colloquium: |
|---|
| Th. 2024-04-25 Perspectives and challenges in the restoration and conservation of two isolated habitats: gypsum and cliffs |
| BayCEER Short Courses: |
| We. 2024-04-24 Mobile Film Making Workshop (for PhDs/PostDosc/Profs of BayCEER) |
| Fr. 2024-04-26 Mobile Film Making Workshop (for students of BayCEER) |
| Ecological-Botanical Garden: |
| Fr. 2024-04-19 now Führung | Gesteine im Ökologisch-Botanischen Garten |
| Su. 2024-04-21 Führung | Den ÖBG kennenlernen: Allgemeine Gartenführung |