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研究了择伐和皆伐对小兴安岭三种森林沼泽土壤氮含量和氮密度的影响。研究结果表明:不同森林沼泽类型的土壤氮含量和氮密度对不同采伐强度的响应不同,采伐对不同土层的氮含量和氮密度的影响也存在差异。(1)采伐一般使落叶松苔草沼泽土壤层的氮含量有所降低,且随着采伐强度增大降低幅度增加;采伐改变了落叶松藓类沼泽土壤层氮含量的分布格局,但对其土壤各层氮含量的影响并不大;采伐虽然对落叶松泥炭藓沼泽土壤氮含量的分布格局有较大影响,但对其各层土壤氮含量的影响相对较弱。(2)就0~50 cm土体的氮密度而言,相对于对照样地,落叶松苔草沼泽择伐后减低1.9%,皆伐后降低40.6%;落叶松藓类沼泽择伐后降低8.8%,皆伐后降低18.3%;落叶松泥炭藓沼泽择伐后增加27.3%,皆伐后降低25.7%。
The effects of selective cutting and clear cutting on nitrogen and nitrogen in three forest swamps in Xiaoxing’an Mountains were studied. The results show that the responses of nitrogen and nitrogen in different forest swamps to different harvesting intensities are different, and the effects of harvesting on nitrogen and nitrogen in different soil layers are also different. (1) Logging generally reduced the nitrogen content in the moss layer of Carex larch, and decreased with the increase of harvesting intensity. Logging changed the distribution of nitrogen content in the moss layer of Larix gmelinii, The effect of nitrogen content in soil layers was not significant. Although the cutting had a significant effect on the distribution pattern of nitrogen in larch peat moss swamp soil, its effect on soil nitrogen content was relatively weak. (2) For the nitrogen density of 0 ~ 50 cm soil, the Larix gmelini marsh decreased by 1.9% after selective cutting and 40.6% after clear cutting, while the larch moss swamp decreased after selective cutting 8.8% after the cutting, 18.3% after the clear cutting. Larix gmelini swamp increased by 27.3% after selective cutting and 25.7% after clear cutting.