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测定了水和氧气对土壤反硝化气体(NO和N_2O)形成的影响.在低温条件下,NO是培育土壤的主要终产物;然而在较湿状态下,N_2O相对量增加.布鲁克斯顿粘土(简称B土)产生的NO和N_3O总量随土壤含水量提高而增加,而福克斯砂壤土(简称F土)含水量为15%时,NO和N_2O总量最高.含水量较高的福克斯砂壤土中,NO和N_2O减少很可能是由于N_2O还原成N_2所致.土壤反硝化气体的存留时间随含水量提高而增长,进一步促进了NO转化成N_2O和N_2.微生物周围的水膜厚度既影响O_2由水扩散到微生物体内也影响反硝化气体(NO、N_2O和N_2)由微生物体内扩散到大气.砂壤土的氧含量和土壤水都影响反硝化气体的排放量和种类.氧气在减少NO产生过程中,含水量低比含水量高更有效.
The effect of water and oxygen on the formation of denitrifying gases (NO and N 2 O) was measured. NO was the main end product of soil incubation at low temperature, while the relative amount of N 2 O was increased under wet conditions. Brookston Clay B soil), the total amount of NO and N_3O increased with the increase of soil water content, while the total content of NO and N_2O was the highest when the water content of Fox sandy loam soil (referred to as F soil) was 15% , The decrease of NO and N_2O is probably caused by the reduction of N_2O to N_2.The residence time of soil denitrification gas increases with the increase of water content and further promotes the conversion of NO to N_2O and N_2.The water film thickness around the microorganism affects both the Diffusion of water into microorganisms also affects the diffusion of denitrifying gases (NO, N 2 O and N 2) into the atmosphere by microorganisms. The oxygen content of sandy loam and soil water all affect the amount and types of denitrification gases emitted. During the reduction of NO production by oxygen, , Low water content is more effective than high water content.