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以中国东北东部4种典型森林生态系统(人工红松林、落叶松林、天然次生蒙古栎林和硬阔叶林)为研究对象,采用静态暗箱-气相色谱法,比较其土壤N2O通量的季节动态及其影响因子.结果表明:在生长季,4种森林生态系统土壤总体上表现为大气N2O的排放源,其N2O通量大小顺序为:硬阔叶林(21.0±4.9μg.m-2.h-1)>红松林(17.6±4.6μg.m-2.h-1)>落叶松林(9.8±5.9μg.m-2.h-1)>蒙古栎林(1.6±12.6μg.m-2.h-1).各生态系统的N2O通量没有明显的季节动态,只在夏初出现排放峰值(蒙古栎林为吸收峰).4种生态系统N2O通量均与10 cm深土壤含水量呈极显著正相关,与NO3--N呈显著负相关;N2O通量对土壤温度和NH4+-N的响应出现分异:针叶林N2O通量与NH4+-N呈显著正相关,而与5 cm深土壤温度呈不相关;阔叶林与针叶林正相反.在较为干旱的2007年,土壤水分是影响4种林型土壤N2O通量的关键因子.植被类型与环境因子及氮素有效性对N2O通量的相互作用将是未来研究的重点.
Four typical forest ecosystems (artificial Korean pine forest, Larix gmelinii forest, natural secondary Quercus mongolica forest and hard broad-leaved forest) in the eastern part of northeast China were studied. Static dark box-gas chromatography was used to compare the season of soil N2O flux The results showed that in the growing season, the soil of four forest ecosystems was generally the source of N2O emission in the order of 21.0 ± 4.9μg.m-2 .h-1)> Pinus koraiensis forest (17.6 ± 4.6μg.m-2.h-1)> Larch forest (9.8 ± 5.9μg.m-2.h-1)> Quercus mongolica forest (1.6 ± 12.6μg.m- -2.h-1) .N2O fluxes of all ecosystems showed no obvious seasonal dynamics, and the emission peak appeared only in early summer (Quercus mongolica forest was the absorption peak) .The N2O fluxes of the four ecosystems were similar to those of 10 cm deep soil There was a significant positive correlation between water content and NO3 - N content and N2O fluxes in response to soil temperature and NH4 + -N: N2O flux in coniferous forest was positively correlated with NH4 + -N And 5 cm depth of soil temperature was not related to; Broadleaved forest and coniferous forest in the opposite.In the more dry in 2007, soil moisture is the key factor affecting the N2O fluxes of four kinds of forest soil.The type of vegetation and environmental factors and nitrogen Prime The effectiveness of the interaction of N2O flux will be the focus of future research.