Abstract
In terrestrial ecosystems, gross nitrogen mineralisation is positively correlated to microbial biomass but negatively to soil organic matter C-to-N ratios; the influence of the microbial community structure is less well known. Here, we relate rates of gross N mineralisation to fungi-to-bacteria ratios in three natural forest types of contrasting N availability and in a long-term N-loading experiment in a boreal forest. We report, for the first time, a strong negative correlation between gross N mineralisation and the fungi-to-bacteria ratio (\( R^{{\text{2}}}_{{{\text{adj}}}} \) = 0.91, P = 0.0005, N = 7). There was also a negative correlation between gross N mineralisation and the C-to-N ratio (\( R^{{\text{2}}}_{{{\text{adj}}}} \) = 0.89, P = 0.001, N = 7), but a weaker positive correlation between gross N mineralisation and soil pH (\( R^{{\text{2}}}_{{{\text{adj}}}} \) = 0.64, P = 0.019, N = 7). Our analysis suggests that soil fungi-to-bacteria and C-to-N ratios are interrelated and that they exert strong influences on soil N cycling in boreal forests.
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We would like to acknowledge financial support from our university (SLU), the Swedish Science Council and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning.
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Högberg, M.N., Chen, Y. & Högberg, P. Gross nitrogen mineralisation and fungi-to-bacteria ratios are negatively correlated in boreal forests. Biol Fertil Soils 44, 363–366 (2007). https://doi.org/10.1007/s00374-007-0215-9
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DOI: https://doi.org/10.1007/s00374-007-0215-9