Soil net nitrogen mineralisation across global grasslands
Risch, A.C.; Zimmermann, S.; Ochoa-Hueso, R.; Schutz, M.; Frey, Beat; Firn, J.L.; Fay, P.A.; Hagedorn, F.; Borer, E.T.; Seabloom, E.W.; Harpole, W.S.; Knops, Johannes M.H.; McCulley, R.L.; Broadbent, A.A.D.; Stevens, C.J.; Silveira, M.L.; Adler, P.B.; Baez, S.; Biederman, L.A.; Blair, J.M.; Brown, C.S.; Caldeira, M.C.; Collins, S.L.; Daleo, P.; Di Virgilio, A.; Ebeling, A.; Eisenhauer, N.; Esch, E.; Eskelinen, A.; Hagenah, Nicole; Hautier, Y.; Kirkman, K.P.; MacDougall, A.S.; Moore, J.L.; Power, S.A.; Prober, S.M.; Roscher, C.; Sankaran, M.; Siebert, J.; Speziale, K.L.; Tognetti, P.M.; Virtanen, R.; Yahdjian, L.; Moser, B.
Date:
2019-10
Abstract:
Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important
for productivity and nutrient cycling. The balance between mineralisation and immobilisation
(net Nmin) varies with soil properties and climate. However, because most global-scale
assessments of net Nmin are laboratory-based, its regulation under field-conditions and
implications for real-world soil functioning remain uncertain. Here, we explore the drivers of
realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We
find that realised Nmin is largely explained by temperature of the wettest quarter, microbial
biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised
Nmin, but contributes to explain realised net Nmin when combined with soil and climatic
variables. We provide novel insights of global realised soil net Nmin and show that potential
soil net Nmin data available in the literature could be parameterised with soil and climate data
to better predict realised N