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The aim of this work was to examine the emission of N2O from soils following addition of nitrogen fertilizer with a nitrification inhibitor(+inh) or without the nitrification inhibitor(-inh) at different soil water regime. Higher soil moisture contents increased the total N2O emissions in all treatments with total emissions being 7 times larger for the CK and >20 times larger for the fertilizer treatments at 85% WFPS(soil water filled pore space ) than at 40% WFPS. The rates of N2O emissions at 40% WFPS under all treatments were small. The maximum emission rate at 55% WFPS without the nitrification inhibitor(-inh) occurred later (day 11) than those of 70% WFPS (-inh) samples (day 8). The inhibition period was 4-22 d for 55% WFPS and 1-15 d for 70% WFPS comparing the rates of N2O emissions treated (+inh) with (-inh). The maximum emission rates at 85% WFPS were higher than those at the other levels of soil water content for all treatments. The samples(+inh) released less N2O than (-inh) samples at the early stage. Nevertheless, N2O emissions from (+inh) samples lasted longer than in the (-inh) treatment. Changes in mineral N at 55%, 70% and 85% WFPS followed the same pattern. NH4-N concentrations decreased while NO3-N concentrations increased from the beginning of incubation. NH4-N concentrations from 40% WFPS treatment declined more slowly than those of the other three levels of soil water content. Nitrification was faster in the (-inh) samples with 100% NH4-N nitrified after 22 d(50% WFPS ) and 15 d(70% and 85% WFPS). N2O emissions increased with soil water content. Adding N-fertilizer increased emissions of N2O. The application of the nitrification inhibitor significantly reduced total N2O emissions from 30.5%(at 85%WFPS) to 43.6%(at 55% WFPS).