Recruitment of coastal planktonic diatoms from benthic versus pelagic cells: Variations in bloom development and species composition

Abstract

Although phytoplankton blooms are major events in aquatic systems, the importance of benthic resting stages in seeding planktonic blooms is still unclear. Using microcosms, we tested the influence of benthic versus planktonic inocula on the development and taxonomic composition of diatom communities in a temperate fjord. Experiments in early spring 2002, fall 2002, and late spring 2003 showed that the type and quantity of inoculum influenced bloom development and composition. Species composition was vastly different when seeded by cells from the benthos. Species such as Detonula confervacea and Thalassiosira minima showed strong dependence on benthic propagules. Populations of Chaetoceros debilis and Thalassiosira nordenskioeldii were initiated by both benthic and planktonic cells, and benthic seeding was most successful when experiments were preceded by a planktonic bloom. Skeletonema costatum was abundant in all treatments but showed variations in size, depending on the type of inoculum. Species that do not have a resting stage, such as Pseudo-nitzschia spp., were present only in planktontreated microcosms. Seasonal factors were especially important in determining the successful growth of newly seeded populations. Our results indicate that benthic resting stages provide an important source for some species. Because the introduction of benthic resting stages to surface waters can greatly influence species composition of the plankton, it is important that studies of plankton blooms include life-history stages from both the sediments and the water column.

Diversity and germination patterns of diatom resting stages at a coastal Mediterranean site

“…Hence, the relatively low number of resting stages recorded in this study might be explained either by the low frequency of sexual events that precede the formation of spores in L. da nicus and/or the numerical dominance of Leptocylindrus species or varieties that do not form resting spores at all. This might also be the reason why L. danicus, while relatively abundant in the plankton, did not show high abundances of resting stages in the sediments collected in a Swedish fjord, and was mostly recorded in microcosms inoculated with phytoplankton samples (McQuoid & Godhe 2004). A considerable fraction of the diatoms that germinated from surface sediments of the Gulf of Naples was constituted by small-sized Thalassiosira-like cells.…”

“…Garrison 1981, Pitcher 1990, Itakura et al 1997, McQuoid & Godhe 2004. As for resting cells, which cannot be distinguished from vegetative cells, information on their presence, abundance and fate in the natural environment is rather elusive (Anderson 1975, but see Härnström et al 2011).…”

Dinoflagellate bloom formation in natural assemblages with diatoms: nutrient competition and growth strategies in Baltic spring phytoplankton

“…It has been shown for complex diatom communities that single species recruitment strategies and conditions prevailing during the seeding stage may significantly affect later community structure and dominance distribution (McQuoid & Godhe 2004). Efficient recruitment from the large benthic seed populations (Kremp 2000, Kremp & Anderson 2000 together with coinciding selective hydrographical conditions obviously are important prerequisites for later dinoflagellate prevalence in the spring phytoplankton community.…”

“…Particularly in multispecies communities, such as the phytoplankton spring bloom in the Baltic Sea, successful prevalence in the competition for resources may entirely depend on initial conditions (Huisman & Weissing 2001). Besides hydrochemical and hydrographic conditions, those may include presence and relative abundance of competitors and grazers, as well as specific recruitment strategies (Anderson et al 2002, McQuoid & Godhe 2004. 'Being in the right place at the right time' may be a more important prerequisite for successful prevalence of a species in a community than favourable habitat conditions or ecophysiological adaptations (Smayda & Reynolds 2001, Anderson et al 2002.…”

Application of real-time PCR assay for detection and quantification of bloom-forming diatom Chaetoceros tenuissimus Meunier

“…Because of its high abundance, it is important to understand the ecology of Chaetoceros in natural waters from the viewpoint of primary production. In the genus, Chaetoceros tenuissimus Meunier is well-known as a cosmopolitan species (Meunier 1913, Hasle & Syvertsen 1996, Sunesen et al 2008, McQuoid & Godhe 2004) and our preliminary study shows that the species causes blooms in the coastal waters in Japan (unpubl.). Shirai et al (2008) reported the existence of a virus infecting C. tenuissimus, however, the host-virus relationships in natural environments are only poorly understood due to the lack of data on the host dynamics.…”