Earthworms (Lumbricus rubellus and Octolasium lacteum) and gut homogenates did not produce CH(inf4), and methanogens were not readily culturable from gut material. In contrast, the numbers of culturable denitrifiers averaged 7 x 10(sup7) and 9 x 10(sup6) per g (dry weight) of gut material for L. rubellus and O. lacteum, respectively; these values were 256- and 35-fold larger than the numbers of culturable denitrifiers in the soil from which the earthworms were obtained. Anaerobically incubated earthworm gut homogenates supplemented with nitrate produced N(inf2)O at rates exceeding that of soil homogenates. Furthermore, living earthworms emitted N(inf2)O under aerobic conditions, and N(inf2)O emission was stimulated by acetylene. For earthworms collected from a mildly acidic (pH 6) beech forest soil, the rates of N(inf2)O emission for earthworms and soil averaged 884 and 2 pmol per h per g (fresh weight), respectively. In contrast, for earthworms collected from a more acidic (pH 4.6) oak-beech forest soil, N(inf2)O emission by earthworms and soil averaged 145 and 45 pmol per h per g (fresh weight), respectively. Based on the extrapolation of this data, earthworms accounted for an estimated 16 and 0.25% of the total N(inf2)O produced at the stand level of these beech and oak-beech forest soils, respectively.
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机译：（（Lumbricus rubellus和Octolasium lacteum）和肠匀浆均不产生CH（inf4），并且不易从肠料中培养产甲烷菌。相比之下，可培养的反硝化剂的数量分别为每g（干重）肠球菌L. rubellus和乳酸乳球菌7 x 10（sup7）和9 x 10（sup6）。这些值比获得the的土壤中可培养的反硝化剂的数量分别大256倍和35倍。厌氧培养的g肠匀浆补充了硝酸盐，产生的N（inf2）O的速率超过了土壤匀浆的速率。此外，活体earth在有氧条件下会排放N（inf2）O，而乙炔会刺激N（inf2）O的排放。对于从中等酸性（pH 6）的山毛榉林土壤中收集的earth，for和土壤的N（inf2）O排放速率分别为每g / g（鲜重）每小时884和2 pmol。相比之下，对于从酸性更高（pH 4.6）的橡木-山毛榉林土壤中收集的worm，earth和土壤的N（inf2）O排放量分别为每g / g（鲜重）每小时145和45 pmol。根据这些数据的推断，earth分别占这些山毛榉和栎木-山毛榉林地林分水平上所产生的N（inf2）O总量的估计16％和0.25％。
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