Riverine phytoplankton, consisting mostly of small-celled cryptophytes
and diatoms (Sobczak et al.
Finally, free-living phytoplankton, including dinoflagellates, cryptophytes
, diatoms, and prymnesiophytes, show no effect of lowered pH (within a range of ~7.
El-Ghareeb and Rezk (1989) provided evidence that therophytes acquire dominance in less saline and more sandy habitats, while cryptophytes
and chamaephytes in more saline habitats.
The vegetation, thus affected, includes shrubs, geophytes, hemi- cryptophytes
, and annuals.
We considered only the life-form categories originally proposed by Raunkiaer: phanerophytes, chamaephytes, hemicryptophytes, cryptophytes
, and therophytes) tend to be under-represented among collections undertaken during just a single period.
Proposed by Raunkiaer (1934), the system classifies plants according to forms used to protect their perennating buds during unfavorable seasons, and groups them into five main classes: therophytes, cryptophytes
, hemicryptophytes, chamaephytes and phanerophytes, according to their different resistance strategies to environmental conditions.
The rest was taken up by cryptophytes
, mainly Cryptomonas spp.
Availability of cryptophytes
(only geophytes) and therophytes confirms the anthropogenic disturbance of the substrate.
Recent advances in the understanding of the physiology (including toxicity), ecology and evolution of the Dinophysiales species are and will be related to the success in culturing Dinophysis species in a three-stage system involving (1) cultivation of cryptophytes
, (2) feeding them to ciliate prey Myrionecta rubra (Lohmann) Jankowski, and (3) feeding of the latter to the Dinophysis cells (Park et al.
and Phanerophytes life forms were dominated in the herbal and regeneration layers, respectively (Table 1).
In each case, the main photosynthetic algae comprised mainly Cryptophytes
, whose dominance of the phytoplankton of Laguna de Guatavita had been noted previously by Orjuela (2004).