生物炭对滨海盐碱土氮素转化和N_(2)O排放的影响  

Effects of biochar application on nitrogen transformation and N_(2)O emission in a coastal saline-alkali soil

作　　者：项剑 孙禧 王成[1] 扎西央宗 史文竹 王艮梅[1] 张焕朝[1] XIANG Jian;SUN Xi;WANG Cheng;Zhaxiyangzong;SHI Wenzhu;WANG Genmei;ZHANG Huanchao(Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京林业大学南方现代林业协同创新中心,南京210037

出　　处：《应用生态学报》2023年第11期2969-2977,共9页Chinese Journal of Applied Ecology

基　　金：江苏省碳达峰碳中和科技创新专项资金项目(BE2022305);国家自然科学青年科学基金项目(41801073);南京林业大学大学生创新创业训练计划项目资助。

摘　　要：生物炭在土壤培肥改良中的应用有助于农业可持续发展和碳中和目标的实现。为更好地了解生物炭对滨海盐碱土氮素转化和N_(2)O排放的影响及其潜在机制,本研究按等氮原则,以仅添加硫酸铵(N 150 mg·kg^(-1),下同)为对照,设置5个处理,即硫酸铵+0.4%生物炭处理(W/W,下同)、硫酸铵+0.6%生物炭处理、硫酸铵+0.8%生物炭处理、硫酸铵+1.6%生物炭处理、硫酸铵+0.2%生物炭+0.2%有机肥处理,进行室内培养试验(60 d)。结果表明:生物炭对土壤氮素转化的影响主要在培养前期,与对照相比,添加生物炭显著增加了滨海盐碱土的硝态氮和铵态氮含量;生物炭显著提高了土壤净硝化速率,且净硝化速率随生物炭添加量的增加而减小;各处理土壤N_(2)O排放的动态变化趋势基本一致,且主要集中在培养前30 d;与对照相比,生物炭添加显著降低了N_(2)O累积排放量,且降幅随添加量的增加而增大。可见,不同添加量生物炭与氮肥配施对土壤氮转化速率和N_(2)O排放的影响不同,其中,0.8%生物炭处理不仅能显著提高土壤无机氮含量,而且能有效降低土壤N_(2)O排放,可作为生物炭改良与培肥滨海盐碱土的最佳剂量。The application of biochar can improve soil fertility and benefit sustainable agricultural development and carbon neutrality simultaneously.To better understand the effects of biochar addition on nitrogen transformation and N_(2)O emission in a coastal saline-alkali soil and its potential mechanisms,we conducted a 60-day laboratory incubation experiment with six treatments,i.e.,ammonium sulfate(N 150 mg·kg^(-1)),ammonium sulfate+0.4%(weight/weight)biochar,ammonium sulfate+0.6%biochar,ammonium sulfate+0.8%biochar,ammonium sulfate+1.6%biochar,and ammonium sulfate+0.2%biochar and 0.2%organic fertilizer(based on equivalent N basis).The results showed that soil nitrogen transformation was mainly affected by biochar addition at the early stage of incubation.Biochar addition significantly increased the contents of nitrate and ammonium.Biochar addition significantly increased soil net nitrification rate,but the magnitude of such increases decreased with increasing biochar addition level.Similar temporal change patterns of N_(2)Oemissions were observed in all treatments,and the N_(2)O emissions mainly occurred in the first 30 days of incubation.Compared with the CK,biochar addition significantly reduced the cumulative N_(2)O emission,and the decrement increased with increasing biochar addition levels.In conclusion,the effects of biochar and nitrogen fertilizer addition on soil nitrogen transformation and N_(2)O emission varied with the application rate.Biochar addition with a rate of 0.8%(W/W)increased soil inorganic nitrogen content and decreased soil N_(2)O emission.It could provide theoretical basis and reference for the formulation of reasonable plans for the improvement and utilization of biochar in coastal saline-alkali soil.

关 键 词：滨海盐碱土 硝化作用 矿化作用 N_(2)O 生物炭 

分 类 号：S156.4[农业科学—土壤学]