沼液施用对潮土氧化亚氮排放通量的影响

通过对潮土养猪沼液施加试验，采用静态箱．气相色谱法于2010年7月（夏季）、2011年3月（冬末春初）观测了不施沼液、正常施沼液及大量施沼液等3种处理的土壤氧化亚氮（N20）排放通量，研究其排放特征与影响因素。研究结果表明：①沼液施用显著提高了氧化亚氮平均排放通量（P〈0．001），不同沼液处理（不施沼液、正常施沼液、大量施沼液）排放通量范围分别为11-25～68147μg·m-2·h-1，20．13～244．35μg·m-2·h-1，40．09～618．43μg·m-2·h-1；②土壤氧化亚氮排放通量除受沼液施加水平影响外，还随着土壤温度的提高而增加：③土壤氧化亚氮排放通量与土壤水分呈极显著相关（P〈0．001）．与土壤硝态氮质量分数显著相关（P〈0．05）；④以相同施氮量计，沼液施加引起的氧化亚氮排放速率远高于尿素或者硫胺等氮肥。图3表1参22

Nitrous oxide emission from an aquic soil after pig slurry application

To determine the characteristics of nitrous oxide （N：O） emissions as well as the relationship between gas emission fluxes and related environmental factors, a pig slurry amendment experiment in an aquie soil was established, and observations of the N20 emissions based on a closed-chamber, gas chromatography-based system in July 2010 （summer） and March 2011 （winter） were made. A field experimental design was employed with three treatments： no（NOF）, normal （NF）, and excessive fertilization （EF）） and each treatment with three replications. Results showed a highly significant increase （P〈0.001） in N20 emissions from this aquic soil with nitrogen fertilizer application. The N20 emissions ranged from 11-25～68147μg·m-2·h-1NOF,from20.13～244.35μg·m-2·h-1NF,and from 40.09～618.43μg·m-2·h-1 for EF with an exponential relation ship between nitrogen application rates and N：O emissions. In addition, soil temperature increases raised N20 emissions. Highly significant exponential relationships （P〉O.001） between N20 emissions and soil moisture, and significant exponential relationships （P〈0.05） between N20 emissions and mass fraction of soil nitrate were also found. When applying the same quantity of N, N20 emissions from the slurry were more than twenty times as much asnitrogen fertilizers such as urea or thiamine. These results indicated that soil temperature, soil moisture and mass fraction of soil nitrate could be important controlling variables for soil N20 fluxes. [ Ch, 3 fig. 1 tab. 22 ref. l