The timing of the commencement of photosynthesis ( P * ) in spring is an important determinant of growing‐season length and thus of the productivity of boreal forests. Although controlled experiments have shed light on environmental mechanisms triggering release from photoinhibition after winter, quantitative research for trees growing naturally in the field is scarce. In this study, we investigated the environmental cues init...

The development of a deep chlorophyll maximum (DCM) at a depth of 30–35 m was followed during a 15‐d case study in July 1998 at the entrance to the Gulf of Finland. The study consisted of three 18–24‐h periods of biological (chlorophyll a , phytoplankton, primary production), chemical (nitrate, phosphate) and physical (CTD, turbulence, vertical particle size distribution) measurements at an anchor station and six mesoscale tow...