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利用静态箱法对贡嘎山森林生态系统峨眉冷杉原始林、演替林以及峨眉冷杉采伐迹地土壤N2O和CH4排放通量进行了测定.结果表明:(1)各观测点土壤向大气释放N2O,土壤为大气N2O的排放源,而CH4的排放通量均为负值,土壤为大气CH4的吸收汇,各观测点N2O年均排放通量的对比关系为峨眉冷杉(Abies fabri)原始林>采伐迹地>演替林,CH4年均吸收通量则表现为峨眉冷杉原始林>演替林>采伐迹地.(2)各观测点N2O排放通量具有明显的季节变化,夏季7-8月以及春季2-3月土壤N2O出现两次排放高峰,冬季及春季3月中旬至4月N2O排放量较低.各观测点CH4吸收强度的季节变化波动强烈,规律不明显.总的来说,演替林和采伐迹地CH4吸收通量均以5月中旬至7月下旬为最高,其余时间较低,而峨眉冷杉原始林到9月份CH4吸收通量仍保持较高的数值.与原始林相比,演替林和采伐迹地的CH4吸收能力要弱些,且采伐迹地的CH4吸收能力更弱,森林砍伐降低了土壤对大气CH4的吸收能力.(3)峨眉冷杉原始林N2O排放通量存在明显日变化规律,且N2O排放通量与气温(r=0.95,n=11,α<0.01)和5cm地温(r=0.81,,n=11,α cutting (2) The N2O emission fluxes of all the observation points have obvious seasonal changes, from July to August in summer and from spring to spring The N2O emission in soil from February to March was the highest, while the N2O emission was lower in the middle and the middle of March to April in winter and spring. The seasonal variation of CH4 absorption intensity at each observation point fluctuated strongly and the law was not obvious. In general, The fluxes of CH4 in the forests and deforested land were the highest from the middle of May to the lowest of July, and the rest of the time was low, while CH4 absorption fluxes of the Abies chensiensis forest kept high until September. Compared with the virgin forest, CH4 is less able to absorb and kill logging stocks and deforested land (3) There was a clear diurnal variation trend of N2O fluxes in Abelmoschus fabri forests, and the N2O fluxes and temperature (r = 0.95, n = 11, α <0.01) and 5cm ground temperature (r = 0.81, n = 11, α <0.01) .Changes in daily variation of CH4 were not significant, and had no significant correlation with temperature and ground temperature.