Impacts of slurry acidification and injection on fertilizer nitrogen fates in grassland

Abstract Low nitrogen (N) use efficiency of broadcast slurry application leads to nutrient losses, air and water pollution, greenhouse gas emissions and—in particular in a warming climate—to soil N mining. Here we test the alternative acidification injection techniques for their mitigation potential compared spreading montane grassland. We determined (1) fate 15 labelled plant-soil-microbe system soil-atmosphere exchange gases over one fertilization/harvest cycle (2) assessed longer-term contribution fertilizer organic formation by end growing season. The isotope tracing approach was combined with space time climate change experiment. Simulated increased productivity, ecosystem respiration, net methane uptake irrespective management, but generally low 2 O fluxes remained unchanged. Compared spreading, showed lowest thus productivity (38% recovery plant aboveground biomass). In contrast, highest total fertilization-induced 9–12 kg ha −1 season . Slurry management effects on CH 4 negligible. sum, our study shows that tested can increase and/or promote from applied remarkable extent. However, this is still not sufficient prevent mining mostly resulting large exports even exceed inputs.