5 10 15
10 Cyanobacteria in the sea. a, b Trichodesmium thiebautii from blooms in the western Atlantic Ocean: a radial 'puff aggregate; b fusiform tuft aggregates from site 26 km off coast ofNorth Carolina, c Contour plot of spatio-temporal distribution of plankton blooms along freshwater (0 km) to estuarine (41 km) salinity gradient in Neuse River Estuary, N. Carolina. Data based on biweekly sampling at 8 stations; carotenoid pigments quantified by HPLC.
d Marine Synechococcus tagged with fluorescently labelled viruses. Synechococcus strain BBC1 has been added to a natural marine microbial community and tagged with cyanophages labelled with the blue fluorescent strain POPO-1. They appear pink, surrounded by a blue halo. Untagged Synechococcus spp. fluoresce red or yellow, while a heterotriophic bacterium has been tagged with a virus that hs been labelled with a green fluorescent stain (YOYO-1).
11 Freshwater blooms in Australia, a Bloom of Anabaena. b Sampling a bloom of Anabaena. c Microcystis aeruginosa, d Planktothrix (= Oscillatoria) perornata (and Anabaena) e Nodularia spumigena from Lake Alexandrine, South Australia, f Anabaena circinalis.
(Photos a,b,d P.D. Baker; c,e,f P.D. Baker & M.D. Burch, Australian Water Quality Centre, South Australia)
12 Examples ot small-celled plankton forms, a Aphanocapsa delicatissima. b Aphanocapsa holsatica. c Cyanodictyon imperfectum. d Cyanodictyon planktonicum. e Cyanodictyon fdiforme. f Tetrarcus ilsteri (All micrographs to same scale: bar = 10 jim) (Photos G. Cronberg)
13 Examples of small-celled plankton forms (con.), a Synechococcus sp. b Chroococcus microscopicus. c Cyanonephron styloides. d Aphanothece clathrata. e Lemmermanniella pallida, f Aphanothece bachmannii (All micrographs to same scale: bar = 10 ^m) (Photos G. Cronberg)
14 Use of fluorescence to study picoplankton. a Typical view of natural picoplankton, together with small aggregates, colonial forms and eukaryotic algae (780 x). b Association of bacteria (blue) and Synechococcus (pink) in a culture stained with DAPI (1250 x). c The ciliate Vorticella coloured with DAPI and visualized under blue excitation, d As previous, but visualized under UV excitation, e Bosmina gut full of autotrophic picoplankton, small colonial forms and eukaryotic cells. (Scale bars for c,d,e = 10 ^m) (Photos C. Callieri)
15 Rice-fields, a Mixed cyanobacterial community on soil of transplanted rice-field, b Dense Lyngbya growth on rice-field soil (Manikganj, Bangladesh), c, d Gloeotrichia colonies on deep water rice plants taken from edge of field at Sonargaon, Bangladesh, e Azolla pinnata grown with transplanted rice (San Fernando, Philippines), f Gloeotrichia natans floating on surface of rice-field drainage ditch two weeks after treatment with weed-killer (International Rice Research Institute, Philippines). (Photos a,b D. Livingstone; c - f B.A. Whitton)
16 Cyanobacteria and limestones, a Tintenstriche on hills by the Li Jiang, Guilin, China, b Hyella in beach-rock, Aldabra Atoll, c, d, e Travertine-depositing sites near Malham, England: c Rivularia colonies in small spring; d Homoeothrix crustacea, showing localization of colonies in more highly illuminated area; e Schizothrix (indicated by reddish colouration of sheaths) on moist travertine surface and adjacent to Pinguicula vulgaris and the moss Gymnostomum recurvirostrum, species with which it is often associated in north temperate regions. (Photos a, c,d,e A. Pentecost; b M. Potts)
18 Cyanobacterial communities in oil-contaminated environment, a General view of cyanobacterial mats on top of oil polluting the intertidal zone of the Arabian Gulf, b Close-up of mat covering heavily contaminated sand, c Close-up of mat on top of contaminated muddy zone. (Photos S.S. Radwan & R.H. Al-Hasan)
19 Cyanobacterial communities in oil-contaminated environments (con.), a General view of non-dissected mats in contamined intertidal, b Close-up of polygonal mats strongly adhering to contaminated sediments, c Surface view of mat at early stage of development on contaminated sand in lower intertidal. (Photos S.S. Radwan & R.H. Al-Hasan)
Plate 20 D
20 Cyanobacteria at southern Victoria Land in the Antarctic, a Cold desert landscape at Beacon Heights, upper Taylor Valley, b Sampling cyanobacteria-dominated cryptoendolithic microbial communities in beacon sandstone at Battleship Promontory. (Photos D.D. Wynn-Williams)
21 Cyanobacteria ofBeacon Sandstone in the Antarctic, a Vertical fracture profile of cryptoendolithic community showing a distinct cyanobacterial zone ~ 6 mm from the surface of the rock; black zone (nearer the surface) contains pigmented lichen, while the white zone comprises mainly hyaline fungi with siome microalgae. b Artificially exposed cyanobacteria (green-brown colouration), hyaline fungi (white), black-pigmented lichen (nearest the surface) of an exfoliating cryptoendolithic community at Timber Peak, Priestley Glacier, central Victoria Land: white label is 6 cm wide. (Photos D.D. Wynn-Williams)
22 Cyanobacteria in hot deserts, a Rocky desert, Negev. b Desertpavement, Negev. c Desert pavement, close-up. d Desertpavement, with one stone overturned to reveal hypolithic cyanobacteria of stone-soil interface, e Surface ofNubian sandstone, with parts chipped off to reveal cryptoendolithic cyanobacterialcolonizationunder the surface, Negev. f Chasmoendolithic colonization in granite shown in thin section of rock, Sonoran Desert, Mexico. (Photos E. I. Friedmann)
23 Old lead - zinc mining areas highly contaminated with Zn Cd and Pb: a-e Missouri, USA; f Einesberger Zentrale, Harz, Germany, a Elvins Tailings, lagoons (5 mg L1 Zn) with planktonic Synechococcus. b Drainage stream (16 mg L1 Zn) at same site showing brown colour due to Plectonema sheaths, c Close-up, with part ofmat sectioned: community is similar to that at many other contaminated sites - mixture of narrow Plectonema and protonemal stage of the moss Dicranella. d Schizothrix community with reddish sheath typical of contaminated alternately wet - dry areas, e Floating mats of mixed populations of narrow sheathed Oscillatoriaceae typical of areas with standing water, f Part of old spoil heap only partially colonized by higher plants and showing dark cover ofmixed Plectonema and moss protonema, which is apparently the typical terrestrial pioneer community of such contaminated areas worldwide. (Photos B .A. Whitton)
24 Nostoc. a N. pruniforme. b Solution hollow on limestone with moist Nostoc commune colonies and associated organic debris permitting growth of higher plant (Portulaca) (Aldabra Atoll): similar solution hollows with N. commune have been reported from many countries, c Nostoc colonies persisting at bottom of empty pool during the dry season on Aldabra Atoll: this 'crumbly' form takes up and loses water more slowly than the typical form, d Spherical colonies ("pearls") ofN. commune growing on agar supplemented with calcium and magnesium carbonates, e Nomarski interference microscopy ofthick section of N. commune thallus, showing brown and yellow layers due to scytonemin; individual filaments visible throughout the extracellular glycan. (Photos aB.A. Whitton&R.W.Castenholz; b,cB.A.Whitton; d,eM.Potts)
25 Scytonema a Colony on upper part of mangrove pneumatophore (near Eilat, Israel), b, c Mats in upper intertidal inland regions ofAndros Is., Bahamas: b polygons consist oflaminated structure trapping particles; c mats developing on surface in sheltered area., d Mats in young transplanted rice-field (Manikganj, Bangladesh), e Hemispherical colonies of S. myochrous, a characteristic species of moist travertine-depositing regions reported from many countries, (see also Plate 2h) (Photos a M. Potts; b,c B.A.Whitton; d,e D.Livingstone)
26 Rivulariaceae are characteristic of sites showing marked temporal or spatial variation in ambient phosphate, a Stream (Upper Teesdale, England: winter) draining region with limestone and peat and with extensive Rivularia cover throughout the year, b Gloeotrichia natans colonies (Bangladesh), c Oncoids (typically 1 - 1.5 cm) formed by small Rivularia colonies in calcareous flush (Sunbiggin, England), d Section of oncoid from this site, e, f Marine intertidal Rivularia (R. atra): e, section of typical colony, showing outer scytonemin-rich layer and intracellular location ofheterocysts; f hormogonia formation following exposure to pulse of elevated phosphate. (Photos a,b,c,e,f B.A.Whitton; d G.A.L. Johnson)
27 "Spirulina" (Arthrospira). a, b Outdoor ponds at Earthrise Farms, California, c Processing "Spirulina" at Earthrise Farms, d Natural population of Arthrospira from African natron water: bar marker = 100 ^m. e Trichome, showing gas vacuoles. (Photos a,b,c Earthrise Farms; d C. Sili; eM. Miihling.
28 Symbiotic associations - macroscopic views, a Gunnera chilensis, including area at base ofleaves containing stem glands infected with Nostoc. b Cycads as an understorey in a newly burnt Eucalyptus forest in Australia, c Sporophyte ofthe fern Azolla pinnata viewed from above; the Nostoc symbiont is contained within swollen dorsal lobes ofthe leaves raised above the water surface, d The liverwort Blasiapusilla showing dark Nostoc colonies scattered around the prominent midrib, e The tripartite lichen Peltigera aphthosa composed of a fungus (seen as white areas at the curled edges), a green alga (colour of main thallus) and Nostoc contained in small dark spots (cephalodia) scattered over a thallus typically 5-8 cm in diameter, f The fungus Geosiphonpyriforme is coloured by its endosymbiotic Nostoc.
(Photos a,c,dD.G. Adams; b,eB. Bergman; f D.Mollenhauer)
29 Symbiotic associations - microscopy, a - c Fluorescence studies with calcofluor white staining: a Ventral surface of Pkaeoceros, showing three stomata-like entrances through which infecting hormogonia gain entry to slime cavities within the thallus; b Ventral surface of Blasia, showing a single auricle as an almost spherical structure on surface of thallus; a slime papilla almost fills the auricle except for a narrow space that appears as a darker, unstained region - this space becomes infected by cyanobacteria and the auricle enlarges as the symbiotic structure develops; c Blasia, showing the red autofluorescence of Nostoc within an enlarged auricle, d Blasia auricle, showing newly developed Nostoc colony surrounding the central slime papilla, e Blasia infected in laboratory with two different Nostoc strains, one blue-green due to chlorophyll and phycocyanin, and the other brown due to the additional phycoerythrin; the colours of the symbiotic colonies can be seen through the auricle walls, f Nostoc isolated from Peltigera apktkosa; heterocystous trichomes occur in packages surrounded by a pronounced mucilaginous sheath. (Photos a,b,c,d, f S. Babic; eB. Bergman)
30 a Scytonemin-rich mat of Calothrix in a tepid hot spring stream (Potts Basin, West Thumb of Yellowstone Lake, Yellowstone National Park), b Cliffface heavily streaked with sheath-pigmented cyanobacteria i.e. Tintenstriche (Numedal,Norway). c Scytonemin-containing Nostoc in melt stream originating from Canada Glacier, Taylor Valley, Antarctica. (Photos R.W. Castenholz)
31 a Scytonemin-rich mat, mainly Lyngbya cf. aestuarii, in hypersaline intertidal flats, Laguna Guerrero Negro, Baja California S., Mexico, b Desert crust in Moab, Utah, showing experimental area with dark coloration due to the high amounts of scytonemin in Nostoc commune, Scytonema spp. and the cyanolichen Collema cristata; note bare soils in quadrats where crusts have been removed and in the walking paths, c, d, e The cyanolichen Collema cf. coccophorum (Arches National Park, Utah) contains high amounts of scytonemin synthesized by Nostoc in its upper lobe, so this region does not fluoresce due to the UVA shielding by scytonemin; lichen lobe is about 1 mm in diameter: c Lobe shown with natural coloration; d Autofluoresecence when excited with green light; e Autofluorescence when excited with UVA radiation. (Photos a R.W.Castenholz; b - d F. Garcia-Pichel)
32 a Lyngbya with scytonemin-rich laminated sheath (trichome ~12 jim diam.). b Gloeocapsa cf. sanguined.with reddish "gloeocapsin" in sheaths (cells ~5 nm diam.). c Scytonema sp. (Culture B-77-Scy.j) showing old filament grown under high irradiance (rich in sheath scytonemin) and new branches grown under low irradiance without scytonemin (axial filament ~14 |im diam.). d Laminated microbial mat from hypersaline pond at Guerrero Negro, Baja California, S. Mexico: upper section had remained under sun throughout the morning, while lower section had been covered with < 10 % transmittance filter for 1.5 h; dark coloration is caused by accumulation of "oscillatorian" cyanobacteria that have migrated to the surface. (Photos: a,c,d R.W. Castenholz; b F. Garcia-Pichel)
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