Abstract: Taking winter wheat and summer maize crop rotation farmland in Northern China Plain as research object, this paper studied the influence of 4 different doses cotton stalk biochar \[CK(control group), C1(2.25 t/hm2 biochar), C2(4.5 t/hm2 biochar), C3(9.0 t/hm2 biochar)\] on soil physical and chemical properties and greenhouse gases (CH4 and N2O) flux in the case of conventional fertilization; and evaluated the impact of different treatments on global warming potential (GWP) and greenhouse gas intensity (GHGI) combining with the production. The results showed that biochar addition could not obviously affect the cumulative CH4 cumulative emission in soil. In summer maize season, only C2 and C3 treatments could remarkably reduce soil N2O emission fluxes by 37.19% and 48.58%, respectively. In winter wheat season, all adding biochar treatments could remarkably reduce the N2O emission fluxes in soil by 24.26%~48.02%. The path analysis results indicated that soil NH+4-N content was the major factor influencing soil N2O emission flux. In summer corn season, C2 and C3 treatments could remarkably increase corn yields by 9.46% and 10.99%, respectively. In winter wheat season, only C3 treatment could remarkably increase wheat yield by 7.13%. Moreover, adding 4.5 t/hm2 and 9 t/hm2 biochar treatments could evidently reduce the GWP and GHGI, while adding 2.25 t/hm2 biochar treatment could only dramatically lower the GWP and GHGI in winter wheat season. To sum up, the conversion of cotton stalk into biochar in farmland in Northern China Plain could not only increase crop yield, but also reduce greenhouse gas emissions.

Key words: biochar, northern China plain, greenhouse gases, comprehensive warming potential, greenhouse gas intensity

摘要： 以我国华北平原冬小麦-夏玉米轮作农田为研究对象，在常规施肥的情况下，研究了4种不同剂量棉花秸秆生物质炭\[CK、C1(2.25 t/hm2生物质炭)、C2(4.5 t/hm2生物质炭)、C3(9.0 t/hm2生物质炭)\]对土壤理化性质及温室气体（CH4、N2O）通量的影响，结合作物产量评估了不同处理对全球温室效应和温室气体强度的影响。结果表明：添加生物质炭不能显著影响土壤CH4的累积排放量。在夏玉米季，仅C2和C3处理可以显著降低土壤N2O累积排放量，分别为37.19%和48.58%；在冬小麦季，添加生物质炭处理均可以显著降低土壤N2O的排放，达24.26%~48.02%。路径分析结果表明，土壤NH+4-N含量是土壤N2O排放通量的主要影响因子。在夏玉米季，C2和C3处理可以显著增加玉米产量，分别达9.46%和10.99%；在冬小麦季，仅C3处理可以显著增加小麦产量，达7.13%。添加4.5 t/hm2和9 t/hm2的生物质炭处理可以显著降低全球增温潜势和温室气体强度，而添加2.25 t/hm2的生物质炭处理仅在冬小麦季可以显著降低全球增温潜势和温室气体强度。综上所述，将棉花秸秆转化为生物质炭用于华北平原农田,既能增加作物产量,又能降低温室气体排放。

关键词: 生物质炭, 华北平原, 温室气体, 综合增温潜势, 温室气体强度