[Short-term Effects of Nitrogen Deposition on CO 2 and CH 4 Fluxes from Wetlands in the Minjiang River Estuary].

In order to evaluate the effects of nitrogen deposition on CO ₂ and CH ₄ fluxes from a Cyperus malaccensis marsh in the Min River estuary at Daoqingzhou, Fujian, static chamber-gas chromatography (GC) techniques were used. CO ₂ and CH ₄ fluxes at a control (CK)[0 g·(m ² ·a) ^-1 ], N1[24 g·(m ² ·a) ^-1 ], N2[48 g·(m ² ·a) ^-1 ], and N3[96 g·(m ² ·a) ^-1 ] were measured and analyzed and the related environmental factors were recorded. The results show that,① compared to the control treatment, the effects of nitrogen deposition on the CO ₂ fluxes for N1 and N3 increased by 20.30% and 4.06%, respectively, whereas the CO ₂ fluxes for N2 reduced by 10.05%, furthermore, the CO ₂ fluxes under different treatments were not significantly different ( P >0.05), except for the N2 and N3 treatments in December ( P <0.05). ② Compared to the control treatment, the effects of nitrogen deposition on CH ₄ fluxes at N1, N2, and N3 were increased by 64.51%, 30.23%, and 80.57%, respectively, whereas the CH ₄ fluxes under different treatments were not significantly different ( P >0.05). ③ There was significant positive correlation between CO ₂ and CH4 fluxes and soil temperature ( P <0.05), however, the CO ₂ and CH ₄ fluxes were not significant with regards to soil pH and soil EC ( P >0.05).