title: Environmental forcing as a main determinant of bloom dynamics of the Chrysochromulina algae.
abstract: In this paper, we demonstrate that the seasonal dynamics in the abiotic factors, without including seasonal changes in the biological relationships, can appropriately account for the seasonal dynamics of Chrysochromulina spp. This is through the analysis of data on the population dynamics of Chrysochromulina spp. off southern Norway that is evaluated in relation to environmental factors and season by the analyses of 12 year monthly time-series. Chrysochromulina spp. abundance, nutrient concentrations, hydrographical properties, as well as current and wind data were analysed on a monthly scale by means of autoregressive moving average models, principal component analyses (PCA), and linear and nonlinear regression models. Seasonal development of the Chrysochromulina assemblage was well predicted from regression models forced with two PCA components representing seasonal variation in nutrient and chlorophyll a levels and ratios, inflow of North Seawater to the Skagerrak and northeasterly wind along the Norwegian coast. Assuming these to be general results, we might hypothesis that marine algal communities are governed by seasonally varying abiotic factors to a large extent.
authors.affiliation: Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway.
authors.forename: Kyrre
authors.initials: K
authors.lastname: Lekve
authors.forename: Espen
authors.initials: E
authors.lastname: Bagøien
authors.forename: Einar
authors.initials: E
authors.lastname: Dahl
authors.forename: Bente
authors.initials: B
authors.lastname: Edvardsen
authors.forename: Morten
authors.initials: M
authors.lastname: Skogen
authors.forename: Nils Chr
authors.initials: NC
authors.lastname: Stenseth
mesh_terms: D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D004777:Environment; D004784:Environmental Monitoring; D056890:Eukaryota / Q000254:growth & development*; D005843:Geography; D008954:Models, Biological; D009664:Norway; D011157:Population Dynamics; D012044:Regression Analysis; D012621:Seasons; D014872:Water Movements; D014919:Wind
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A