The influence of management and environmental variables on soil N2O emissions in a crop system in Southern Italy

Abstract

Soil N 2 O emissions were monitored throughout a 3-year crop rotation including maize, fennel and a ryegrass-clover sward, at Borgo Cioffi NitroEurope site. N 2 O emission rates were highly variable in time and space and controlled by soil nitrogen and soil water content. The N 2 O effluxes were low for most of the monitored period. The highest N 2 O emissions were recorded throughout the 2007 maize cropping season, ranged form 15.2 to 196.2 μg m −2 h −1 whereas the lowest ones ranged form −5 to 10 μg m −2 h −1 during the 2007-2008 ryegrass-clover winter crop. For the maize crops, N 2 O peaks were detected after fertilization but with a delay of some weeks from applications, probably due to the presence of DMPP nitrification inhibitor in the applied fertilizer. A properly designed ANOVA model was developed to explain the influence of the main chemical-physical factors. This model also allowed the quantification of the delay time in peak emissions following fertilization, which resulted variable over the years and ranged between 2 and 21 days. A dependence of emissions from soil temperature and moisture was found, with significant interactions in some instances. Calculated Emission Factors (maize 2007: 0.48%; ryegrass-clover sward 2007-2008: 0.05%; maize 2008: 0.14%; fennel: 0.28% 2008-2009; maize 2009: 0.015%) resulted well below the values reported in the literature and the 1% reference value indicated by IPCC, probably due to a suboptimal water regime inducing low Water Filled Pore Space (WFPS) values.

Fertilizer type influences tomato yield and soil N₂O emissions

“…In fact, soil temperatures remained close to 20°C in all treatments (data not shown) beyond which the 3,4-dimethylpyrazole phosphate degradation is accelerated (Zerulla et al 2001, Vitale et al 2013. The effectiveness of DMPP to mitigate N 2 O production determined an emission factor (EF1) smaller than 0.2% in both sites (C ridge = 0.45%, C furrow = 0.12%; DMPP ridge = 0.16%, DMPP furrow = 0.12%; OM ridge = 0.26%, OM furrow = 0.07%), comparable to the values reported in others studios (Ranucci et al 2011, Vitale et al 2013 and lower that those estimated for mineral and organo-mineral fertilizers, confirming the efficiency of 3,4-dimethylpyrazole phosphate into contrasting NH 4 + -N oxidation also in soils with coarse texture (Vitale et al 2013).…”

“…Fertilizers supply greater than the crop demand can lead to nitrogen loss from soil due to NO 3 --N leaching and N 2 O/NO production by microbial processes (i.e. nitrification and denitrification), with a negative impact on climate and environment.Improved crop management techniques have been suggested to reduce the soil N 2 O emission and to improve crop production (Rees et al 2013, Snyder et al 2014, including the use of fertilizer added with nitrification inhibitor (NI) (Ranucci et al 2011, Vitale et al 2013) and organic manure (Ball et al 2004). The use of NI-added fertilizers offers several advantages compared to conventional ones because it increases fertilizer use efficiency with positive effects on plant growth and crop yields and inhibits NH 4 + -N oxidation, and in turn soil NO 3 --N content, thus limiting N 2 O production.…”

Impact of the size of nitrogen fertiliser application rate on N₂O flux

“…Agriculture contributes to the increase in atmospheric N 2 O, accounting for 24% of global annual emissions (IPCC 2007). Nitrous oxide (N 2 O) is among the most important greenhouse gases, contributing by 6% to global warming (Loubet et al 2011;Ranucci et al 2011), and directly affects the stratospheric ozone layer (Willianms et al 1992;Ravishankara et al 2009). Nitrous oxide emitted from soils leads to N loss from the ecosystem and is produced by nitrification and denitrification microbiological activities (Skiba et al 1993;Ambus et al 2006;Jiang-Gang et al 2007;Senbayram et al 2012) and chemodenitrification at low pH (< 5.5) (Van Cleemput, Samater 1996).…”

A Newly Practice to Mitigate N2O Emission from Winter Wheat Soil by Intercropping Isatis indigotica

“…This was the first report of new land use pattern by co-cropping herbal plant to mitigate N 2 O emitted from agricultural soil. Compared to some other agricultural practices such as N fertilizer management (KAISER et al, 1998;Ulrike et al, 2003;Chu et al, 2007;Fub et al, 2011;Aguilera et al, 2013;Fisk et al, 2015;Frederico et al, 2015), reduced tillage (Fub et al, 2011;Fisk et al, 2015;Frederico et al, 2015), drip irrigation and fertigation (Aguilera et al, 2013;Kennedy et al, 2013), organic amendments (Qiu et al, 2013;Aguilera et al, 2013;Fisk et al, 2015), crops straw incorporation (Ma et al, 2009;Yang et al, 2015), biochar (Xiang et al, 2015), nitrification inhibitor (Ranucci et al, 2011;Barneze et al, 2015), this newly developed approach could be more effective and economical as it was simple and easily to conduct in a low-cost manner for farmer. Of course, it needs to be further improved and optimized.…”