中文摘要：

以玉米田作为研究对象，分析了土壤呼吸速率的季节变化规律及环境因子的作用，旨在通过了解农田CO2吸收与排放的动态变化，为探索该地区碳收支机理提供试验依据。试验采用静态箱气相色谱（GC）法测定了下辽河平原典型玉米田的土壤呼吸速率。结果表明，玉米田土壤呼吸速率具有明显的变化规律，玉米生长旺盛期土壤呼吸速率值保持在较高水平，3种处理的平均土壤呼吸速率分别为：施N肥处理（N150）为215．67mg·m^-2·h^-1；未施N肥处理（N0）为192．48mg·m^-2·h^-1；无作物对照（CK）为137．13mg·m^-2·h^-1。土壤温度Q10和土壤水分是影响土壤呼吸的重要因素。地下5cm的土壤温度与土壤呼吸有显著的相关性。在夏季（6至8月）的土壤水分与土壤呼吸间存在较为明显的互为消长关系。施肥可明显增强土壤呼吸作用，N150比N0处理土壤呼吸总量增加了12．1％，N150和N0处理的土壤呼吸总量分别是CK处理的1．57和1．40倍。

英文摘要：

Experiments were conducted at the Shenyang Ecology Experimental Station of the Chinese Academy of Sciences in 2004 to investigate the soil respiration of the maize fields. CO2 was collected and analyzed by the GC （static-chamber） method at a frequency of twice a week for each treatment. In order to find the relationship between the CO2 emission and the impact factors, the soil temperature and soil moisture etc. were observed in the meanwhile. The results indicated that there was significant seasonal variation of soil respiration in maize fields. The respiration rates were lower in spring and autumn and higher in summer. The average soil respiration rate was 215.67 mg·m^-2·h^-1 in N150 treatment, 192.48 mg· m^-2· h^-1 in No treatment and 137.13 mg· m^-2· h^-1 in CK treatment. The soil temperature and soil moisture were two important factors influencing soil respiration. There was remarkable correlation between soil respiration and underground 5 cm soil temperature. The correlation between respiration and soil moisture was also apparent from June to August, but it was not significant during the whole growing season. Fertilization could increase the intensity of soil respiration. The total soil respiration of nitrogen fertilizer treatment was 12.1% more than the treatment without nitrogen fertilizer. The respiration in three treatments was N150〉N0〉CK.