2024-03-28T21:42:55Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/217322022-12-29T09:56:57Zcom_10261_123com_10261_8com_10261_132col_10261_376col_10261_385
2010-03-01T08:22:32Z
urn:hdl:10261/21732
Alexandrium minutum resting cyst distribution dynamics in a confined site
Anglès, Silvia
Jordi, Antoni
Garcés, Esther
Basterretxea, Gotzon
Palanques, Albert
Alexandrium minutum
Mediterranean Sea
Resting cyst
Resuspension
Sediment dynamics
Seiche
Special issue Phytoplankton Life-Cycles and Their Impacts on the Ecology of Harmful Algal Bloom.-- 12 pages, 12 figures, 1 table
The life cycle of the toxic dinoflagellate Alexandrium minutum consists of an asexual stage, characterized by motile vegetative cells, and a sexual stage, a resting cyst that once formed remains dormant in the sediment. Insight into the factors that determine the distribution and abundance of resting cysts is essential to understanding the dynamics of the vegetative phase. In investigations carried out between January 2005 and January 2008 in Arenys de Mar harbor (northwestern Mediterranean Sea), the spatial and temporal distribution patterns of A. minutum resting cysts and of the sediments were studied during different bloom stages of the vegetative population. Maximum cyst abundance was recorded mainly in the innermost part of the harbor while the lowest abundance always occurred near the harbor entrance, consistent with the distribution of silt-clay sediment fractions. The tendency of cysts in sediments to increase after bloom periods was clearly associated with new cyst formation, while cyst abundance decreased during non-bloom periods. Exceptions to this trend were observed in stations dominated by the deposition of coarse sediments. High correlation between the presence of cysts and clays during non-bloom periods indicates that cysts behave as passive sediment particles and are influenced by the same hydrodynamic processes as clays. In Arenys de Mar, the main physical forcing affecting sediment resuspension is the seiche, which was studied using in situ measurements and numerical models to interpret the observed distribution patterns. During non-bloom periods, cyst losses were smaller when the seiche was more active and at the station where the seiche-induced current was larger. Thus, seiche-forced resuspension appears to reduce cyst losses by reallocating cysts back to the sediment surface such that their burial in the sediment is avoided. The observed vertical profiles of the cysts were consistent with this process
2010-03-01T08:22:32Z
2010-03-01T08:22:32Z
2010-02
artículo
Deep Sea Research - Part II - Topical Studies in Oceanography 57(3-4): 210-221 (2010)
0967-0645
http://hdl.handle.net/10261/21732
10.1016/j.dsr2.2009.09.002
eng
Postprint
https://doi.org/10.1016/j.dsr2.2009.09.002
openAccess
Elsevier