Separated pathways for biochar to affect soil N2O emission under different moisture contents.
Separated pathways for biochar to affect soil N2O emission under different moisture contents.
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DOI：
10.1016/j.scitotenv.2018.07.224
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发表时间：
2018-07
期刊：
影响因子：
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通讯作者：
Zhengjun Feng;Yaqi Sheng;Fei Cai;Wen Wang;Lizhong Zhu
中科院分区：
文献类型：
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作者：
Zhengjun Feng;Yaqi Sheng;Fei Cai;Wen Wang;Lizhong Zhu
旱地是全球氧化亚氮（N2 O）排放的重要来源，生物炭是一种潜在的土壤改良材料，可以影响土壤N2 O排放。鉴于旱地土壤含水量的多变性，研究不同含水量条件下生物质炭对土壤N2 O排放的影响具有重要意义。因此，用两种生物炭（B300和B500，分别在300和500 ℃下热解的生物炭）在五种水分含量（18%、21%、24%、27%和30%，w/w）下进行柱实验。结果表明，B300通过提高土壤溶解性有机碳含量，促进土壤微生物对N2 O的释放，从而促进土壤水分含量为18%、21%和24%时N2 O的释放。当水分含量为27%和30%时，由于B300增加了nosZ tonirS的丰度比，N2 O排放量减少，从而抑制了N2 O的产生。B500对土壤中溶解性有机质含量的影响不显著，因此在含水量为18%、21%和24%时，对N2 O排放量的影响不显著。但当土壤含水量为27%和30%时，土壤中nosZ tonirS的丰度比增加，N2 O排放量减少。研究结果进一步阐明了生物质炭对土壤N2 O排放的影响，并有助于评价生物质炭抑制土壤N2 O排放的潜力。
Dry land is a massive contributor to global nitrous oxide (N2O) production and biochar is a potential material for soil amendment that can impact soil N2O emission. Considering that the moisture content of dry land is usually changeable, it is essential to investigate the effect of biochar on soil N2O emission under different moisture contents. Therefore, column experiments were conducted with two biochars (B300 and B500, biochars pyrolyzed at 300 and 500 °C, respectively) under five moisture contents (18%, 21%, 24%, 27% and 30%, w/w). The results showed that B300 promoted N2O emission under the moisture contents of 18%, 21% and 24% by increasing the content of dissolved organic carbon and thus enhancing the microbial processes related to N2O production. However, when the moisture contents were 27% and 30%, the promotion of N2O production was overwhelmed by the improvement in N2O reduction due to the B300 induced increase in the abundance ratio ofnosZ tonirS, leading to the decrease in N2O emission. Moreover, B500 did not alter the content of dissolved organic matter significantly and thus caused no significant change in N2O emission when the moisture contents were 18%, 21% and 24%. But it was able to increase the abundance ratio ofnosZ tonirS and thus decrease N2O emission when the moisture contents were 27% and 30%. The results further clarified the effect of biochar on soil N2O emission and helped to evaluate the N2O-suppressing-potential of biochar.