【摘要】 为了解施用生物炭对杨树人工林土壤CO₂、CH₄、N₂O3种温室气体排放的长期影响及其主要调控机理,以东台国有林场杨树人工林为对象,设置低生物炭添加量(D,40 t·hm^-2)、中生物炭添加量(Z,80 t·hm^-2)、高生物炭添加量(G,120 t·hm^-2)及对照(CK,0 t·hm^-2)4种不同处理,采用静态箱-气相色谱法对CO₂、CH₄、N₂O3种温室气体的排放速率进行了多次测定,同时测定分析了土壤含水率、土壤酶活性等土壤理化及生化指标,为阐明生物炭对杨树人工林生态系统的长期影响提供理论依据。结果表明:（1）对照样地土壤CO₂排放速率变化范围为123.428-412.066mg·m-2·h-1,中、高生物炭添加处理显著促进了土壤CO₂的排放（P=0.001、0.000）,分别导致CO₂年平均排放速率增加了21%和20%;（2）对照样地土壤CH4排放速率变化范围为0.578-1.405 mg·m-2·h-1,中、高生物炭添加处理显著抑制了土壤CH₄的排放（P=0.000、0.000）,分别导致CH4年平均排放速率降低了21%和33%;（3）对照样地土壤N2O排放速率变化范围为0.124-0.297mg·m-2·h-1,中、高生物炭添加处理显著抑制了土壤N2O的排放（P=0.003、0.000）,分别导致N₂O年平均排放速率降低14%和37%;（4）土壤CO₂排放主要与土壤微生物量C（MBC）、水溶性有机碳（DOC）、全氮（TN）、蔗糖酶活性（IA）呈显著正相关关系（P=0.000、0.000、0.013、0.000）,与土壤微生物量N（MBN）、土壤微生物量P（MBP）呈显著负相关关系（P=0.000、0.000）;（5）土壤CH4排放和N2O排放主要与MBN、MBP、土壤含水率（SMC）、蛋白酶活性（PA）、脲酶活性（UA）、IA呈显著正相关关系（PCH4=0.011、0.009、0.005、0.000、0.000、0.007;PN2O=0.021、0.024、0.002、0.000、0.001、0.019）,与MBC、DOC、TN呈显著负相关关系（PCH4=0.000、0.003、0.002;PN2O=0.001、0.012、0.001）。综上,添加生物炭导致了土壤N、P养分有效性增加和蛋白酶、脲酶等相关酶活性降低,可能是本区域生物炭调控杨树人工林土壤3种温室气体排放的主要机制。更多还原

【Abstract】 In order to understand the long-term effects of biochar application on soil CO₂, CH₄ and N₂O emissions under poplar plantation and the main regulatory mechanism, and to provide a theoretical basis for elucidation of the long-term effects of biochar on poplar plantation ecosystem. In the poplar plantation of Dongtai forest center, we measured three types of soil greenhouse gas emission rates using static box-gas chromatography method in four different biochar treatments. The treatments included low quantity biochar addition(D, 40 t·hm^-2), middle quantity biochar addition(Z, 80 t·hm^-2), high quantity biochar addition(G, 120 t·hm^-2) and contrast(CK, 0 t·hm^-2) with four replications for each treatment. Soil physical and chemical indicators such as soil moisture content and soil enzyme activities were also analyzed. The results showed that:（1） Soil CO₂ emission rate of CK ranged from 123.428 to 412.066 mg·m^-2·h^-1, only Z and G treatments significantly promoted soil CO₂ emission rate（P=0.001, 0.000）,resulting in a 21% and 20% increase of annual average emission rate, respectively.（2） Soil CH₄ emission rate of CK ranged from0.578 to 1.405 mg·m^-2·h^-1, only Z and G treatments significantly inhibited soil CH₄ emission rate（P=0.000, 0.000）, resulting in a21% and 33% decrease of annual average emission rate, respectively.（3） Soil N₂O emission rate of CK ranged from 0.124 to 0.297 mg·m-2·h-1, only Z and G treatments significantly inhibited soil N₂O emission rate（P=0.003, 0.000）, resulting in a 14% and 37%decrease of annual average emission rate, respectively.（4） Soil CO₂ emissions were positively correlated with soil microbial biomass C（MBC）, dissolved organic carbon（DOC）, total nitrogen（TN）, and invertase enzyme activity（IA）（P=0.000, 0.000, 0.013, 0.000）,but negatively correlated with soil microbial biomass N（MBN） and soil microbial biomass P（MBP）（P=0.000, 0.000）. And（5） soil CH₄ and N₂O emissions were positively correlated with MBN, MBP, soil moisture content（SMC）, protease activity（PA）, urease activity（UA） and IA（PCH₄=0.011, 0.009, 0.005, 0.000, 0.000, 0.007; PN₂O=0.021, 0.024, 0.002, 0.000, 0.001, 0.019）, and negatively correlated with MBC, DOC and TN（PCH₄=0.000, 0.003, 0.002; PN₂O=0.001, 0.012, 0.001）. The results indicate that biochar may promote soil N, P availability and inhibit activities of soil protease, urease and other related enzymes, which potentially is the main mechanism of biochar to regulate the emissions of three greenhouse gases in this region.更多还原