Primary production at time series station DYFAMED

Phytoplankton carbon assimilation has been measured near monthly using the 14C method at DYFAMED France JGOFS time-series station from 1993 to 1999. Data were obtained using the “LET GO” technique, which allowed in situ injection of bicarbonate and incubation in enclosures at 10 depths. Incubation duration was 4 h around noon, from which daily production was estimated. The seasonal variation of the depth-integrated carbon assimilation exhibits a marked cycle. Maximum values reach 1.8 g C/m**2/d in March or April; constant lower values were observed from August to January, in the range 100-300 mg C/m**2/d. The annual primary production vary in the range 86-232 g C/m**2/yr, in the upper range of older estimations. Primary production normalized to chlorophyll a shows maximum values in the period of oligotrophy. […]

自1993年至1999年，在法国DYFAMED JGOFS时间序列站，通过14C方法对浮游植物碳固定进行了近似每月一次的测量。数据采集采用“LET GO”技术，该技术允许现场注入碳酸氢盐，并在10个深度层次的围栏内进行培养。培养时间定于正午前后4小时，据此估算每日产量。深度积分碳固定的季节性变化呈现出显著的周期性。最大值在3月或4月达到1.8克碳/平方米/日；从8月至次年1月，观察到恒定的较低值，范围为100-300毫克碳/平方米/日。年总初级生产力变化范围在86-232克碳/平方米/年之间，位于以往估计的上限区间。将初级生产力标准化至叶绿素a后，在寡营养期显示出最大值。