C.5 Freshwater phytoplankton: diversity & biology http://www.youtube.com/watch?v=98Ra2q1ZqUU C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.1 Identifying freshwater phytoplankton 'algae' a large & very diverse: ~15 groups (divisions) freshwater vs. marine cf. benthic: stonewarts (Charophyta), red algae (Rhodophyta) size, 1 ~500 ㎛; nano ~microplankton ranges * DNA-based molecular techniques @identifying species @morphological features w/ microscope - size, shape & colour of cells - arrangement of cells (single, filamentous, colonial) - type of cell wall - P/A & position of flagella, organelles, specialised cells   Bold & Wynne 1986 South & Whittick 1987 Van den Hoek et al. 1995 Lee 1999 Sandgren 1988a C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.2 Cyanobacteria (blue-green algae) BOX 5.1 Cyanobacteria & other photosynthetic bacteria BOX 5.2 Buuoyancy regulation in cyanobacteria ~ bacteria Prokaryotes > Kingdom Eubacteria ~ higher plants cf. all other algae belong to eukaryotes ! N2 fixation: leguminous plants BOX 5.3 Heterocytes & Akinetes Gram-negative bacteria, w/ lipopolysaccharides (potent toxins) commonly @most freshwaters; also @marine &terrestrial 3 orders of Australia: [Tab 5.1] - Chroococcales: Microcystis aeruginosa (hepatotoxin), M. flosaquae, picoplanktonic Chroococcus Merismopedia Aphanocapsa Aphanothece Coelosphaerium - Nostocales: most problem, Anabaena circinalis (neurotoxin, bloom), A. spiroides, Cylidrospermopsis raciborskii (hepatotoxin); Cuspidothrix Aphanizomenon Anabaenopsis - Oscillatoriales: no hepato- neuro-toxin spp.; a toxic benthic Phormidium sp. & Lynbya wollei ; Planktothrix Planktolynbya Pseudanabaena Geitlerinema Planktotrichoides C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.3 Chlorophyceae (green algae) most numerous & diverse ~11 orders (~19 ord.), non-toxic majority of planktonic sp.; blooms @nutrient-enriched Chlorophyceae(녹조강) prim. freshwater group ~90% - attached & benthic, planktonic ord. Volvocales: Chlamydomonas, Gonium, Pandorina, Eudorina, Volvox, Pediastrum훈장말, Scenedesmus뗏목말, Desmodesmus, Chlorella, Oocystis Desmids장구말, w/ two mirror-image halves, conjugation for zygote : Closterium, Cosmarium, Micrasterias, Staurastrum C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.4 Bacillariophyceae (diatoms) widely dist. freshwater & marine planktonic, benthic, epiphytic [BOX 5.5] planktonic: single, colony, filamentous cell wall @silica w/ hypo- & epivalve ! valve view vs. girdle view Centrales: centric, radial Cyclotella Coscinodiscus Aulacoseirra Pennales: pennate, bilateral Synedra Urosolenia Navicula; Asterionella Fragilaria Tabellaria; Cocconeis Surirella Pinularia   BOX 5.6 Vegetative reproduction in diatoms C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.5 Pyrrhophyceae (or Dino-; Dinoflagellates) 'dinos' fewer @freshwater than marine harmless @freshwater [BOX 5.7] usual. single-celled, some filamentous epicone+hypocone, w/ theca, two flagella - armoured dinos: Peridinium Ceratium - naked: Gymnodinium C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.6 Other algae flagellated, motile algae euglenoids div.Euglenophyceae: common @fresh [BOX 5.8] - Euglena, Phacus; Trachelomonas cryptomonads div.Cryptophyceae: @lentic [BOX 5.9] - Cryptomonas, Rhodomonas golden-brown algae div.Chrysophyceae: @slightly acidic [BOX 5.10] - Mallomonas, Synura; Dinobryon C.5 Freshwater Phytoplanktn

C.5 Freshwater Phytoplanktn 5.7 Conclusions ~7 divisions @freshwater - common 3 orders of cyanobacteria - great diversity @green algae: flagellated vs. non-flagella. - centric vs. pennate of diatoms - armoured vs. naked of dinoflagellates & euglenoids C.5 Freshwater Phytoplanktn