FN Archimer Export Format PT J TI Comment. What drives plankton seasonality in a stratifying shelf sea? Some competing and complementary theories BT AF ATKINSON, Angus POLIMENE, Luca FILEMAN, Elaine S. WIDDICOMBE, Claire E. MCEVOY, Andrea J. SMYTH, Tim J. DJEGHRI, Nicolas SAILLEY, Sevrine F. CORNWELL, Louise E. AS 1:1;2:1;3:1;4:1;5:1;6:1;7:2;8:1;9:1; FF 1:;2:;3:;4:;5:;6:;7:;8:;9:; C1 Plymouth Marine Lab, Prospect Pl, Plymouth PL1 3DH, Devon, England. UBO, IUEM, CNRS, Lab Sci Environm Marin,UMR 6539, Plouzane, France. C2 PML, UK UBO, FRANCE UM LEMAR IF 4.325 TC 11 UR https://archimer.ifremer.fr/doc/00616/72768/88226.pdf LA English DT Article AB The Plymouth L4 time plankton series in the Western English Channel is a textbook example of a shallow, stratifying shelf sea system. Over its 30 yr of weekly sampling, this site has provided a diverse and contrasting suite of numerical and conceptual models of plankton bloom formation, phenology, and seasonal succession. The most recent of these papers, Kenitz et al. (2017) has initiated this comment, partly because we feel that it has presented a slightly misleading picture of the plankton composition at this site, and of a robust, recurring seasonal succession. We address this by illustrating the extent of inter-annual variability in phenology that occurs at the site, and which needs to be captured better within models. However our main aim is to foster a much better integration of the variety of top-down and bottom-up processes that have all been suggested to be key in driving seasonal succession. Some of these, particularly the multiple grazing and growth controls contributing to the so-called "loophole hypothesis" may be complementary, but others, such as the role of copepod feeding traits in driving species succession (Kenitz et al. 2017) offer testable competing hypotheses. The basic assumptions and outputs of all these models need to be validated more critically, both against time series data and process studies that include the finding of unselective feeding. We suggest that the variability in plankton phenology (and not just mean timing and amplitude) could be used to diagnose the performance of alternative models of plankton succession. PY 2018 PD NOV SO Limnology And Oceanography SN 0024-3590 PU Wiley VL 63 IS 6 UT 000450233300040 BP 2877 EP 2884 DI 10.1002/lno.11036 ID 72768 ER EF