Phenological Changes of Blooming Diatoms Promoted by Compound Bottom-Up and Top-Down Controls.

Guinder, Valeria A., Molinero, Juan Carlos, López Abbate, Celeste M., Berasategui, Anabela A., Popovich, Cecilia A., Spetter, Carla V., Marcovecchio, Jorge E. and Freije, Rubén H. (2017) Phenological Changes of Blooming Diatoms Promoted by Compound Bottom-Up and Top-Down Controls. Estuaries and Coasts, 40 (1). pp. 95-104. DOI 10.1007/s12237-016-0134-9.

[img] Text
art%3A10.1007%2Fs12237-016-0134-9.pdf - Published Version
Restricted to Registered users only

Download (1310Kb) | Contact

Supplementary data:

Abstract

Understanding phytoplankton species-specific responses to multiple biotic and abiotic stressors is fundamental to assess phenological and structural shifts at the community level. Here, we present the case of Thalassiosira curviseriata, a winter-blooming diatom in the Bahía Blanca Estuary, Argentina, which displayed a noticeable decrease in the past decade along with conspicuous changes in phenology. We compiled interannual field data to assess compound effects of environmental variations and grazing by the invasive copepod Eurytemora americana. The two species displayed opposite trends over the period examined. The diatom decreased toward the last years, mainly during the winters, and remained relatively constant over the other seasons, while the copepod increased toward the last years, with an occurrence restricted to winter and early spring. A quantitative assessment by structural equation modeling unveiled that the observed long-term trend of T. curviseriata resulted from the synergistic effects of environmental changes driven by water temperature, salinity, and grazing. These results suggest that the shift in the abundance distribution of T. curviseriata toward higher annual ranges of temperature and salinity—as displayed by habitat association curves—constitutes a functional response to avoid seasonal overlapping with its predator in late winters. The observed changes in the timing and abundance of the blooming species resulted in conspicuous shifts in primary production pulses. Our results provide insights on mechanistic processes shaping the phenology and structure of phytoplankton blooms.

Document Type: Article
Funder compliance: info:eu-repo/grantAgreement/EC/FP7/603773
Keywords: Plankton, Grazing selectivity, Phenology, Structural equation modeling, Estuaries
Research affiliation: OceanRep > GEOMAR > FB3 Marine Ecology > FB3-EOE-N Experimental Ecology - Food Webs
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1007/s12237-016-0134-9
ISSN: 1559-2723
Projects: OCEAN-CERTAIN, Future Ocean
Date Deposited: 11 Aug 2016 10:12
Last Modified: 01 Feb 2019 15:08
URI: http://oceanrep.geomar.de/id/eprint/33567

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...