Cyanobacteria from freshwater lakes in the Azores Archipelago, Portugal

Study Extent

Phytoplankton samples from 24 lakes in Corvo (1), Flores (6), Pico (5), and São Miguel (12) islands in the Azores archipelago were collected seasonally between 1996 and 2018.

Sampling

Phytoplankton samples were taken using Van Dorn bottle and a 10 µm mesh plankton net at lake maximum depth point. In deep lakes (maximum depth > 10 m), until 2010 discrete samples were collected at surface, mid-water column depth and 1 m above sediment. After 2010 a combined sample of the euphotic zone was obtained by mixing discrete 1 L samples collected at 1 m intervals from the surface to the bottom of the euphotic zone. In shallow lakes (maximum depth < 10 m) a surface sample (integrated sample of the first meter of the water column) was collected. Net samples were obtained by a trawl from 1 m above the sediment to the water column surface. All samples were preserved with 1% Lugol solution (v/v) and taxa were identified to the lower taxonomical level possible using light microscopy. Preserved samples after analysis were deposited in Faculdade de Ciências e Tecnologia, Universidade dos Açores.

Method steps

1. Cyanobacteria were identified according to Komárek and Anagnostidis (1998), Komárek and Anagnostidis (2008) and Komárek (2013).

Cyanobacteria were identified to genus or species level. Nomenclature was updated to the most recent taxonomic treatment.

1. Cyanophyceae Schaffner
   common name: Cyanophyceae rank: class

Azores Archipelago, Portugal