太湖地区水稻土长期不同施肥条件下油菜季土壤呼吸CO2排放

利用长期定位试验研究了太湖地区不同施肥处理下油菜生长期间水稻土CO2排放通量，耕作方式为水稻-油菜轮作，并对CO2排放通量和土壤（5cm）温度、土壤水分含量进行了回归模拟。结果表明，不同施肥处理平均土壤呼吸CO2排放速率在49．37～85．97CO2-Cmg·m^-2·h^-1之间，与不施肥处理相比，长期施用肥料显著提高了土壤呼吸CO2排放速率，且在油菜的两个生育期，施肥对土壤呼吸释放CO2的促进作用，花角期显著高于角果发育成熟期。相关分析表明，土壤呼吸CO2排放强度与土壤水分、土壤温度有显著的正相关关系。通过计算Q10，无肥处理（NF）较其他肥料处理（CF、CFM、CFS）对土壤温度有更大的敏感性。

CO2 Emission Under Long-term Different Fertilization During Rape Growth Season of a Paddy Soil from Tailake Region,China

CO2 emission was monitored in-situ in a long-term fertilization station located in Tai Lake Region during rape growth season. The paddy soil has been continuously cultivated with rice-rape rotation since 1987. Soil temperature at 5 cm, air temperature and soil water content were also measured simultaneously with soil reparation. The average soil respiration rates among different fertilization treatments were ranged form 49.37-85.97 CO2-C mg·m^-2·h^-1 Application of fertilizers intensively promoted the emission rates of CO2 compared with no fertilization treatment. Soil respiration was significantly correlated with soil moisture and soil temperature at 5 cm. No fertilization（NF） treatment plot had relatively higher Q10 value than plots with chemical fertilizers only （CF）, chemical fertilizers plus manure （CFM）and chemical fertilizers plus straw（ CFS ）.