三峡库区不同土地利用方式下土壤氧化亚氮排放及其影响因素

采用静态箱-气相色谱法对菜地、旱地、林地、果园、水改旱土壤N₂O排放特征及其相关影响因子进行研究.结果表明：不同土地利用方式下土壤N₂O的排放通量在-21～435 μg·m^-2·h^-1之间变化，N₂O年排放总量为菜地>果园>旱地>水改旱>林地，分别为447.14、313.57、167.00、124.87和7.24 mg·m^-2.土壤N₂O排放通量呈现明显的季节性变化，以春夏季最高，秋季次之，冬季最低，并与对应的大气及土壤温度的变化趋势基本一致.N₂O排放通量与5 cm土壤温度及土壤硝态氮含量呈显著或极显著正相关，与土壤水分及土壤铵态氮含量无明显相关关系.

Soil N2O flux and its affecting factors under different land use patterns in Three Gorges Reservoir Area of China.

By using static chamber techniques, the N2O emission from soils under different land use patterns was measured. The results showed that the N2O flux ranged from -21 to 435 microg x m(-2) h(-1), and the annual N2O flux was decreased in the order of vegetable field > orchard > upland > upland transferred from paddy field > woodland, being 447.14, 313.57, 167.00, 124.875 and 7.24 mg x m(-2), respectively. The N2O flux presented significant seasonal fluctuation, with the maximum in spring and summer, followed by in autumn, and the minimum in winter, which was approximately consistent with the changes of air- and soil temperature. N2O flux had significant positive correlation with the soil temperature at 5 cm depth and soil NO3(-)-N content, but no significant correlation with soil moisture and NH4(+)-N contents.