采用热脱附-气相色谱/质谱联用（TDS-GC/MS）技术对侧柏〔Platycladus orientalis (Linn.) Franco〕枝叶挥发性有机物(VOCs)的月份（7月至11月）差异和日变化进行检测分析。结果表明：在侧柏枝叶VOCs中鉴定出133个化合物，化合物总数在9月和13:00—14:00最多（均为74），各月份和时段的烯烃类化合物数量和相对含量最高，且烯烃类相对含量在上午低于下午、夜晚低于白天。综上所述，侧柏枝叶VOCs以烯烃类为主，且化合物数量和相对含量存在明显的月份差异和日变化规律。

 The monthly (July to November) differences and diurnal changes of volatile organic compounds (VOCs) from branches and leaves of Platycladus orientalis (Linn.) Franco  were detected and analyzed by using thermal desorptiongas chromatography/mass spectrometry (TDS-GC/MS) technology. The results show that 133 compounds are identified in VOCs from branches and leaves of P. orientalis, the total number of compounds is the largest (both 74) in September and 13:00-14:00, the compound numbers and relative contents of alkenes in each month and period are the highest, and the relative contents of alkenes are lower in the morning than in the afternoon, and lower in the night than in the day. In conclusion, VOCs in branches and leaves of P. orientalis are mainly alkenes, and there are obvious rhythms of monthly differences and diurnal changes in numbers and relative contents of compounds.