分析官厅水库夏季（8月份）叶绿素a浓度短时变化特征，对于水库水体富营养化研究具有重要意义。利用以分钟为步长的水温、水深及叶绿素a浓度实测数据及气象数据，对叶绿素a浓度垂向及昼夜变化特征进行了分析。结果表明：叶绿素a浓度最高值是表层浓度的1.5～2倍，其出现位置与温度跃层位置基本一致。叶绿素a浓度具有昼夜周期性变化特征。白昼，温度跃层以上叶绿素a浓度随水深增加逐渐增加，在温度跃层以下，随水深增加逐渐降低；夜间，温跃层以上叶绿素a浓度基本稳定不变，在温度跃层以下与白昼变化趋势相同。表层水体叶绿素a浓度夜间大于白天，且与光照及表层水温呈负相关。水库叶绿素a浓度短时分布特征主要与温度分层以及限制性营养盐磷的释放有关。

Chlorophyll-a concentration at Guanting Reservoir in summer (August) were analyzed. The analysis has great significance to the study of reservoir water eutrophication. The data of water temperature, water depth, chlorophyll-a concentration, and meteorological data were measured at an interval of one minute, and were analyzed. The results showed that the maximum concentration of chlorophyll-a appeared at basically the same position as that of the thermocline, and it was 1.5-2 times of the surface concentration value. Chlorophyll-a concentration showed circadian variation. During daytime, chlorophyll-a concentration above the thermocline increased as water depth increased; yet below the thermocline, it decreased as water depth increased. At night, the chlorophyll-a concentration below the thermocline had the same variation trend as it had in the daytime; but above the thermocline, it was basically stable. The surface chlorophyll-a concentration was higher at night than during the daytime, and showed a negative correlation with the surface temperature and illumination. The short-term distribution of chlorophyll-a concentration at Guanting Reservoir in summer was mainly related to the temperature stratification and the release of the limiting nutrient phosphorus.

国家重点研发计划课题(2016YFC0401308)；中央高校基本科研业务费专项资金项目；国家自然科学基金资助项目(41671018)