Nitrous oxide emission and the related denitrifier community: A short-term response to organic manure substituting chemical fertilizer
Nitrous oxide emission and the related denitrifier community: A short-term response to organic manure substituting chemical fertilizer
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DOI：
10.1016/j.ecoenv.2020.110291
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发表时间：
2020-04-01
影响因子：
6.8
通讯作者：
Gao, Ming
中科院分区：
文献类型：
--
作者：
Huang, Rong;Wang, Yingyan;Gao, Ming
用有机肥部分替代化肥，有利于农业废弃物的循环利用，减少化肥用量，影响氮素转化。然而，关于菜地短期替代有机肥后土壤理化性质、反硝化菌群落与N2O排放之间关系的研究相对较少。我们进行了短期蔬菜田间试验，包括1个对照(CT，不施肥)和3个等量全N、P、K的施肥处理(CF，只施化肥；CMR，化肥+蘑菇渣；COM，化肥+牛粪)。结果表明，部分有机肥替代化肥显著提高了累积N2O排放量、N2O排放系数和产量尺度N2O排放量，分别提高了122-203%、238-600%和128-181%。与化肥处理相比，短期有机肥替代降低了NIRS和NOSZ型反硝化细菌的丰度，增加了NirK型反硝化细菌的丰度。模型表明，土壤有效N、NIR活性、NirK丰度、SOC、NH4+和NO3-是影响N2O累积排放的主要因素。秸秆还田土壤的反硝化细菌群落组成与CMR和COM处理的土壤完全不同，主要受土壤NH4+浓度的影响。NIR活性与反硝化细菌群落组成呈显著正相关。总体而言，短期用牛粪替代化肥(较低的C/N比)降低了NIRS-和NOSZ型反硝化细菌的丰度，但刺激了N2O的排放。
Partially substituting chemical fertilizer with organic manure can aid in the disposal of agricultural wastes via recycling into agricultural land, reduce chemical fertilizer application, and influence nitrogen (N) transformation. However, relatively few studies have investigated the association between soil physicochemical properties, denitrifier communities and N2O emission after short-term substitution of organic manure in vegetable fields. We conducted a short-term vegetable field experiment which included one control treatment (CT, no fertilizer) and three fertilization treatments containing equal amount of total N, phosphorus and potassium (CF, chemical fertilizer only; CMR, chemical fertilizer plus mushroom residue; COM, chemical fertilizer plus cattle manure). The results showed that partial substitution of chemical fertilizer with organic manure greatly increased cumulative N2O emissions, N2O emission factors and yield-scaled N2O emissions by 122-203%, 238-600% and 128-181%, respectively. Compared with the CF treatment, short-term substitution with organic manure reduced the abundance of nirS- and nosZ-type denitrifiers, and increased that of nirK-type denitrifiers. Modeling indicated that nirS abundance, together with soil available N, NIR activity, nirK abundance, SOC, NH4+, and NO3- were the primary factors associated with cumulative N2O emissions. The denitrifier community composition of the CFtreated soil was separated from that of soils treated with CMR and COM, and was primarily influenced by soil NH4+ concentration. NIR activity showed a significant correlation with denitrifier community composition. Overall, short-term substitution of chemical fertilizer with cattle manure (lower C/N ratio) reduced the abundance of nirS- and nosZ-type denitrifiers, but stimulated N2O emission.