State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China; College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, 210098, China.
State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China; College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, 210098, China.
Environ Pollut. 2018 Nov;242(Pt A):257-263. doi: 10.1016/j.envpol.2018.06.103. Epub 2018 Jun 30.
Pulse diffusive nitrous oxide (NO) emission following water application is well documented, whereas NO emission caused by soil water-air displacement during the watering process (termed as soil degassing) has been largely overlooked. Watering-induced NO emissions from ten different soils in China were quantified, and found to range from 74.4 ± 6.7 to 678.1 ± 36.6 μg NO m h in surface watered (SW) soils, and from 45.6 ± 4.4 to 358.1 ± 23.6 μg NO m h in subsurface watered (SUW) soils. These NO fluxes were much larger than the diffusive NO flux from the same soil either under dry (7.9%-9.6% water filled pore space, WFPS) or wet (85.1%-93.6% WFPS) conditions. The watering process (the water infiltration process upon irrigation/rainfall or the process of shallow groundwater uplifting) resulted in massive NO emissions.
水灌溉后脉冲扩散一氧化二氮（NO）排放已有大量记录，而在浇水过程中（称为土壤脱气）由于土壤水-气置换导致的 NO 排放则被很大程度上忽视了。本研究量化了来自中国的十种不同土壤的浇水诱导 NO 排放，发现地表浇水（SW）土壤中的 NO 排放范围为 74.4±6.7 至 678.1±36.6μg NO m h，而地下浇水（SUW）土壤中的 NO 排放范围为 45.6±4.4 至 358.1±23.6μg NO m h。这些 NO 通量远大于相同土壤在干燥（7.9%-9.6%含水孔隙空间，WFPS）或湿润（85.1%-93.6%WFPS）条件下的扩散性 NO 通量。浇水过程（灌溉/降雨时的水渗透过程或浅层地下水上涌过程）导致了大量的 NO 排放。
