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Journal articles on the topic 'Algae – Namibia'

Author: Grafiati
Published: 4 June 2021
Last updated: 2 February 2022

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1

Rull Lluch, Jordi. "Marine benthic algae of Namibia." Scientia Marina 66, S3 (December 30, 2002): 5–256. http://dx.doi.org/10.3989/scimar.2002.66s35.

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2

Grant, S. W. F., A. H. Knoll, and G. J. B. Germs. "Probable calcified metaphytes in the latest Proterozoic Nama Group, Namibia: origin, diagenesis, and implications." Journal of Paleontology 65, no. 1 (January 1991): 1–18. http://dx.doi.org/10.1017/s002233600002014x.

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Samples from the Huns Limestone Member, Urusis Formation, Nama Group, at two adjacent localities in southern Namibia contain thin foliose to arched, sheet-like carbonate crusts that are 100–500 µm thick and up to 5 cm in lateral dimension. Morphologic, petrographic, and geochemical evidence supports the interpretation of these delicate crusts as biogenic, most likely the remains of calcified encrusting metaphytes. The original sediments of the fossiliferous samples contained aragonitic encrusting algae, botryoidal aragonite cements, and an aragonite mud groundmass. Spherulites within the precursor mud could represent bacterially induced mineral growths or the concretions of marine rivularian cyanobacteria. Original textures were severely disrupted during the diagenetic transition of aragonite to low-magnesian calcite, but some primary structures remain discernible as ghosts in the neomorphic mosaic. Gross morphology, original aragonite mineralogy, and hypobasal calcification indicate that the crusts are similar to late Paleozoic phylloid algae and extant peyssonnelid red algae. Structures interpreted as possible conceptacles also suggest possible affinities with the Corallinaceae.Two species of Cloudina, interpreted as the remains of a shelly metazoan, are also known from limestones in the Nama Group. It is possible, therefore, that skeletalization in metaphytes and animals arose nearly simultaneously near the end of the Proterozoic Eon.
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3

Highfield, Andrea, Angela Ward, Richard Pipe, and Declan C. Schroeder. "Molecular and phylogenetic analysis reveals new diversity of Dunaliella salina from hypersaline environments." Journal of the Marine Biological Association of the United Kingdom 101, no. 1 (January 22, 2021): 27–37. http://dx.doi.org/10.1017/s0025315420001319.

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AbstractTwelve hyper-β carotene-producing strains of algae assigned to the genus Dunaliella salina have been isolated from various hypersaline environments in Israel, South Africa, Namibia and Spain. Intron-sizing of the SSU rDNA and phylogenetic analysis of these isolates were undertaken using four commonly employed markers for genotyping, LSU rDNA, ITS, rbcL and tufA and their application to the study of Dunaliella evaluated. Novel isolates have been identified and phylogenetic analyses have shown the need for clarification on the taxonomy of Dunaliella salina. We propose the division of D. salina into four sub-clades as defined by a robust phylogeny based on the concatenation of four genes. This study further demonstrates the considerable genetic diversity within D. salina and the potential of genetic analyses for aiding in the selection of prospective economically important strains.
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4

Maneveldt, G. W., D. W. Keats, and Y. M. Chamberlain. "Synarthrophyton papillatum sp. nov.: A new species of non-geniculate coralline algae (Rhodophyta, Corallinales, Hapalidiaceae) from South Africa and Namibia." South African Journal of Botany 73, no. 4 (November 2007): 570–82. http://dx.doi.org/10.1016/j.sajb.2007.05.003.

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5

Keats, D. W., and G. Maneveldt. "Two new melobesioid algae (Corallinales, Rhodophyta), Synarthrophyton robbenense sp. nov. and S. munimentum sp. nov., in South Africa and Namibia." Phycologia 36, no. 6 (November 1997): 447–67. http://dx.doi.org/10.2216/i0031-8884-36-6-447.1.

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6

Tokarev, D. A., A. V. Plyusnin, A. A. Terleev, N. A. Ivanova, I. V. Varaksina, and A. V. Lipyanina. "NEW RESULTS OF INTEGRATED LITHOFACIES AND BIOSTRATIGRAPHICAL STUDY OF THE LOWER CAMBRIAN OSA HORIZON IN THE SOUTH OF THE SIBERIAN PLATFORM (BOLSHETIRSKAYA 7 WELL)." Geology and mineral resources of Siberia, no. 2 (2021): 56–66. http://dx.doi.org/10.20403/2078-0575-2021-2-56-66.

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The section of the Osa Subformation of the Usolka Formation of the Lower Cambrian Tommotian stage penetrated by the Bolshetirskaya 7 well in the south of the Nepa-Botuoba anteclise has been studied. As a result of lithological-facies investigations, seven lithological types of rocks were identified, they are regularly replaced by each other along the section. Facies environments of the reef complex were dеtected: bar bank, rear part of the reef, organogenic bioherm bildup, reef rear bars, reef buildup, core of reef buildup. In the section of the subformation, three fourth-order sequences are identified. The sequence boundaries are fixed by subaerial hiatuses represented in the core by sedimentation breccias, karst zones. The largest lowering of sea level, in terms of amplitude and duration, is confined to the border of the second and third sequences. The conducted biostratigraphic analysis confirms the Lower Cambrian age. Remains of calcareous algae Renalcis polymorphum, R. gelatinosum, R. granosum, Botomaella zelenovi were found. Small shell fauna of the genus of Namacalathus Grotzinger, Watt ers et Knoll. also was found. It has global distribution in the Lower Vendian (Ediacaran) deposits in Namibia, Brazil, Canada, Oman, Spain, China, Russia, etc.
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7

GROTZINGER, J., E. W. ADAMS, and S. SCHRÖDER. "Microbial–metazoan reefs of the terminal Proterozoic Nama Group (c. 550–543 Ma), Namibia." Geological Magazine 142, no. 5 (September 2005): 499–517. http://dx.doi.org/10.1017/s0016756805000907.

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Thrombolite and stromatolite reefs occur at several stratigraphic levels within the terminal Proterozoic Nama Group (c. 550–543 Ma) of central and southern Namibia. The reefs form integral parts of several carbonate platforms within the Nama Group, including the Kuibis platform of the northern Nama Basin (Zaris subbasin), and Huns platform (Witputs subbasin) of the southern Nama Basin. The reefs are composed of both thrombolites and stromatolites that form laterally continuous biostromes, isolated patch reefs, and isolated pinnacle reefs ranging in scale from a metre to several kilometres in width. In the majority of cases, the reefs occur stratigraphically as an integral facies within the transgressive systems tracts of sequences making up the Kuibis and Huns platforms. This suggests that a regime of increasing accommodation was required to form well-developed reefs, though reefs also occur sporadically in highstand systems tract settings. Within a given transgressive systems tract, a regime of increasing accommodation through time favours the transition from sheet-like biostromal geometries to more isolated patch and pinnacle biohermal geometries. Similarly, increasing accommodation in space, such as a transect down depositional dip, shows a similar transition from more sheet-like geometries in updip positions to more isolated geometries in downdip positions. Reefal facies consist of thrombolitic domes, columns and mounds with well-developed internal clotted textures, in addition to stromatolitic domes, columns and mounds, with crudely to moderately well-developed internal lamination. Stromatolites are better developed in conditions of relatively low accommodation, and updip locations, under conditions of higher current velocities and greater sediment influx. Thrombolites are better developed in conditions of relatively high accommodation and low sediment influx. Both types of microbialites are intimately associated with the first calcifying metazoan organisms, which may have attached themselves to the sediment surface or otherwise lived within sheltered depressions within the rough topography created by ecologically complex mats. The appearance of thrombolitic textures during terminal Proterozoic time is consistent with colonization of cyanobacterial mats by higher algae and metazoans, which would have been an important process in generating clotted textures. Fabrics in the Nama thrombolites are well preserved and show evidence of thrombolitic mesoclots being overgrown by fibrous marine carbonate, interpreted as former aragonite. This was followed by emplacement of geopetal micrite fills, and precipitation of dolomite as an isopachous rim cement, followed by occlusion of remaining porosity by blocky calcite spar.
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8

van Aarde, Rudi J., Stuart L. Pimm, Robert Guldemond, Ryan Huang, and Celesté Maré. "The 2020 elephant die-off in Botswana." PeerJ 9 (January 11, 2021): e10686. http://dx.doi.org/10.7717/peerj.10686.

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The cause of deaths of 350 elephants in 2020 in a relatively small unprotected area of northern Botswana is unknown, and may never be known. Media speculations about it ignore ecological realities. Worse, they make conjectures that can be detrimental to wildlife and sometimes discredit conservation incentives. A broader understanding of the ecological and conservation issues speaks to elephant management across the Kavango–Zambezi Transfrontier Conservation Area that extends across Botswana, Namibia, Angola, Zambia, and Zimbabwe. Our communication addresses these. Malicious poisoning and poaching are unlikely to have played a role. Other species were unaffected, and elephant carcases had their tusks intact. Restriction of freshwater supplies that force elephants to use pans as a water source possibly polluted by blue-green algae blooms is a possible cause, but as yet not supported by evidence. No other species were involved. A contagious disease is the more probable one. Fences and a deep channel of water confine these elephants’ dispersal. These factors explain the elephants’ relatively high population growth rate despite a spell of increased poaching during 2014–2018. While the deaths represent only ~2% of the area’s elephants, the additive effects of poaching and stress induced by people protecting their crops cause alarm. Confinement and relatively high densities probably explain why the die-off occurred only here. It suggests a re-alignment or removal of fences that restrict elephant movements and limits year-round access to freshwater.
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9

Retallack, Gregory J. "Were the Ediacaran fossils lichens?" Paleobiology 20, no. 4 (1994): 523–44. http://dx.doi.org/10.1017/s0094837300012975.

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Ediacaran fossils are taphonomically similar to impressions of fossil plants common in quartz sandstones, and the relief of the fossils suggests that they were as resistant to compaction during burial as some kinds of Pennsylvanian tree trunks. Fossils of jellyfish are known from siderite nodules and fine-grained limestone, and even in these compaction-resistant media were more compressed during burial than were the Vendobionta. Vendobionta were constructed of materials that responded to burial compaction in a way intermediate between conifer and lycopsid logs. This comparative taphonomic study thus falsifies the concept of Vendobionta as thin soft-bodied creatures such as worms and jellyfish.Lichens, with their structural chitin, present a viable model for the observed preservational style of Vendobionta, as well as for a variety of other features that now can be reassessed from this new perspective. The diversity of Ediacaran body plans can be compared with the variety of form in fungi, algae, and lichens. The large size (ca. 1 m) of some Ediacaran fossils is reasonable for sessile photosynthetic symbioses, and much bigger than associated burrows of metazoans not preserved. Microscopic tubular structures and darkly pigmented cells in permineralized late Precambrian fossils from Namibia and China are also compatible with interpretation as lichens. The presumed marine habitat of Ediacaran fossils is not crucial to interpretation as lichens, because fungi and lichens live in the sea as well as on land.
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10

van Aarde, Rudi J., Stuart L. Pimm, Robert Guldemond, Ryan Huang, and Celesté Maré. "The 2020 elephant die-off in Botswana." PeerJ 9 (January 11, 2021): e10686. http://dx.doi.org/10.7717/peerj.10686.

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The cause of deaths of 350 elephants in 2020 in a relatively small unprotected area of northern Botswana is unknown, and may never be known. Media speculations about it ignore ecological realities. Worse, they make conjectures that can be detrimental to wildlife and sometimes discredit conservation incentives. A broader understanding of the ecological and conservation issues speaks to elephant management across the Kavango–Zambezi Transfrontier Conservation Area that extends across Botswana, Namibia, Angola, Zambia, and Zimbabwe. Our communication addresses these. Malicious poisoning and poaching are unlikely to have played a role. Other species were unaffected, and elephant carcases had their tusks intact. Restriction of freshwater supplies that force elephants to use pans as a water source possibly polluted by blue-green algae blooms is a possible cause, but as yet not supported by evidence. No other species were involved. A contagious disease is the more probable one. Fences and a deep channel of water confine these elephants’ dispersal. These factors explain the elephants’ relatively high population growth rate despite a spell of increased poaching during 2014–2018. While the deaths represent only ~2% of the area’s elephants, the additive effects of poaching and stress induced by people protecting their crops cause alarm. Confinement and relatively high densities probably explain why the die-off occurred only here. It suggests a re-alignment or removal of fences that restrict elephant movements and limits year-round access to freshwater.
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11

Knoll, Andrew H. "The advent of the Phanerozoic world: Vendian stratigraphy, environmental change, and evolution." Paleontological Society Special Publications 6 (1992): 169. http://dx.doi.org/10.1017/s2475262200007292.

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The Vendian interval (ca. 610–540 Ma) links Proterozoic and Phanerozoic worlds of sharply contrasting character. Despite decades of study, the nature of this transition remains unclear, in part because of our limited ability to correlate Vendian successions or evaluate shifts in global environments. New data on secular variations in the C and Sr isotopic compositions of Vendian carbonates (and organic matter) provide an improved stratigraphic and biogeochemical framework for understanding latest Proterozoic biological and environmental evolution.Biologically, the Vendian interval is best known for the Ediacaran radiation of macroscopic animals, but this event is set within a broader Neoproterozoic diversification of higher eukaryotes. All three principal groups of multicellular algae radiated well before the beginning of the Vendian, as did a host of unicellular protists. In particular, successions deposited immediately after the Varanger Ice Age (ca. 610–590 Ma) are characterized by a high diversity of large and morphologically complex acritarchs; most of these forms disappeared after the first appearance of Ediacara-grade metazoans but before the eponymous fauna preserved in South Australia.Stratigraphic ordering of the earliest faunas is made possible by chemostratigraphy. Contrary to some published expectations, the morphologically complex petalonemids and skeletalized cloudinids of the lower Nama Group, Namibia, appear to predate, perhaps significantly, the classic faunas of South Australia, eastern Siberia, and elsewhere. Zircon ages for tuffs promise an absolute chronology for biological and biogeochemical events. The presence in pre-Cambrian rocks of Cloudina, calcareous algae and (?)siliceous discs comparable to chrysophyte scales demonstrates that eukaryotic calcite, aragonite, and silica biomineralization all predate the beginning of the Cambrian; however, sedimentological and petrographic features of carbonates and cherts suggest that skeletons first emerged as globally significant components of the carbon and silica cycles with the basal Cambrian radiation.Vendian evolution must also be evaluated within a broader context of environmental change. The Sr and C isotopic data that enhance stratigraphic correlation also record patterns of hydrothermal emission and organic carbon burial that must have affected pO2. Independent models by Derry and others and Knoll and Walker suggest that latest Proterozoic reductions in the hydrothermal flux of reduced materials into the oceans coupled with high burial rates of organic carbon resulted in a significant increase in global oxygen levels immediately prior to the great Ediacaran radiation.Many questions about Vendian evolution remain unresolved. Some will surely require fresh insights into the development and functional morphology of early metazoans, but it is becoming increasingly clear that a satisfactory accounting of Ediacaran animal diversification will not be achieved without a better understanding of the stratigraphic, environmental, and biological context in which it occurred.
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12

Knott, Michael G., and Anthony Ishola. "Chemotaxonomy as a Potential Method to Rapidly Identify Various Namibian Plocamium Species." Natural Product Communications 13, no. 12 (December 2018): 1934578X1801301. http://dx.doi.org/10.1177/1934578x1801301238.

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Differentiating between different Plocamium species of marine algae is not a trivial task. However, a literature review reveals that each species of Plocamium has a major and minor metabolite that is unique to a particular Plocamium species being investigated. Knowledge about the chemotaxonomy of these unique major and minor metabolite standards therefore enables the potentially rapid identification of Plocamium species by means of either 1H NMR or GC-MS analysis of crude Plocamium extracts.
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13

Shiyanga, Aina N., Michael Knott, and Petrina Kapewangolo. "In vitro Anti-HIV and Antimicrobial Activities of a Halogenated Monoterpene from a Namibian Plocamium Species of Marine Algae." Current Bioactive Compounds 16, no. 3 (June 10, 2020): 363–67. http://dx.doi.org/10.2174/1573407215666190111153845.

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Background: The marine red alga Plocamium naturally produces halogenated monoterpenes with varied biological activities. In our continuing efforts to discover new lead compounds for the treatment of HIV/AIDS as well as novel antibacterial compounds, various Namibian Plocamium species have been investigated. Methods: A rare but known compound namely 1E,3R,4S,5E,7Z-1-bromo-3,4,8-trichloro-7- (dichloromethyl)-3-methylocta-1,5,7-triene (1) was isolated from a Namibian Plocamium red alga. The anti-HIV activity of compound 1 was investigated against three HIV enzymes namely, HIV protease, reverse transcriptase and integrase. In addition, compound 1 was also screened for antibacterial activity against selected microbes using the disc diffusion method. Results: Compound 1 demonstrated selective in vitro inhibition against HIV-1 integrase with a 50% inhibition concentration of <0.06 mM. Weak inhibitory activity was observed against HIV-1 reverse transcriptase and protease. Compound 1 also showed antibacterial activity against Staphylococcus aureus (ATCC 25923), Alcaligenes faecalis (ATCC 8750) and Serratia marcescens (ATCC 8100) with MIC values of 0.65 mM, and 1.29 mM for Klebsiella pneumonia (ATCC 13883). Conclusion: The results of this study highlight the potential of halogenated monoterpenes from red seaweed as possible leads in the development of new anti-HIV and antimicrobial pharmaceuticals.
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14

Shapumba, Christ W., Michael Knott, and Petrina Kapewangolo. "Antioxidant activity of a halogenated monoterpene isolated from a Namibian marine algal Plocamium species." Journal of Food Science and Technology 54, no. 10 (August 28, 2017): 3370–73. http://dx.doi.org/10.1007/s13197-017-2784-4.

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15

Grotzinger, John P., Wesley A. Watters, and Andrew H. Knoll. "Calcified metazoans in thrombolite-stromatolite reefs of the terminal Proterozoic Nama Group, Namibia." Paleobiology 26, no. 3 (2000): 334–59. http://dx.doi.org/10.1666/0094-8373(2000)026<0334:cmitsr>2.0.co;2.

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Reefs containing abundant calcified metazoans occur at several stratigraphic levels within carbonate platforms of the terminal Proterozoic Nama Group, central and southern Namibia. The reef-bearing strata span an interval ranging from approximately 550 Ma to 543 Ma. The reefs are composed of thrombolites (clotted internal texture) and stromatolites (laminated internal texture) that form laterally continuous biostromes, isolated patch reefs, and isolated pinnacle reefs ranging in scale from a meter to several kilometers in width. Stromatolite-dominated reefs occur in depositionally updip positions within carbonate ramps, whereas thrombolite-dominated reefs occur broadly across the ramp profile and are well developed as pinnacle reefs in downdip positions.The three-dimensional morphology of reef-associated fossils was reconstructed by computer, based on digitized images of sections taken at 25-micron intervals through 15 fossil specimens and additionally supported by observations of over 90 sets of serial sections. Most variation observed in outcrop can be accounted for by a single species of cm-scale, lightly calcified goblet-shaped fossils herein described as Namacalathus hermanastes gen. et sp. nov. These fossils are characterized by a hollow stem open at both ends attached to a broadly spheroidal cup marked by a circular opening with a downturned lip and six (or seven) side holes interpreted as diagenetic features of underlying biological structure. The goblets lived atop the rough topography created by ecologically complex microbial-algal carpets; they appear to have been sessile benthos attached either to the biohermal substrate or to soft-bodied macrobenthos such as seaweeds that grew on the reef surface. The phylogenetic affinities of Namacalathus are uncertain, although preserved morphology is consistent with a cnidarian-like bodyplan. In general aspect, these fossils resemble some of the unmineralized, radially symmetric taxa found in contemporaneous sandstones and shales, but do not appear to be closely related to the well-skeletonized bilaterian animals that radiated in younger oceans. Nama reefs demonstrate that biohermal associations of invertebrates and thrombolite-forming microorganisms antedate the Cambrian Period.
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16

Keats, D. W., and Y. M. Chamberlain. "Heydrichia groeneri sp. nov.: a new species of crustose coralline alga (Rhodophyta, Sporolithaceae) from South Africa and Namibia." Phycologia 34, no. 1 (January 1995): 51–57. http://dx.doi.org/10.2216/i0031-8884-34-1-51.1.

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17

Schröder, S., A. Ibekwe, M. Saunders, R. Dixon, and A. Fisher. "Algal–microbial carbonates of the Namibe Basin (Albian, Angola): implications for microbial carbonate mound development in the South Atlantic." Petroleum Geoscience 22, no. 1 (December 23, 2015): 71–90. http://dx.doi.org/10.1144/petgeo2014-083.

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18

Kapalanga, Taimi S., Zvikomborero Hoko, Webster Gumindoga, and Loyd Chikwiramakomo. "Remote sensing-based algorithms for water quality monitoring in Olushandja Dam, north-Central Namibia." Water Supply, October 29, 2020. http://dx.doi.org/10.2166/ws.2020.290.

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Abstract Frequent and continuous water quality monitoring of Olushandja Dam in Namibia is needed to inform timely decision making. This study was carried out from November 2014 to June 2015 with Landsat 8 reflectance values and field measured water quality data that were used to develop regression analysis-based retrieval algorithms. Water quality parameters considered included turbidity, total suspended solids (TSS), nitrates, ammonia, total nitrogen (TN), total phosphorus (TP) and total algae counts. Results show that turbidity levels exceeded the recommended limits for raw water for potable water treatment while TN and TP values are within acceptable values. Turbidity, TN, and TP and total algae count showed a medium to strong positive linear relationship between Landsat predicted and measured water quality data while TSS showed a weak linear relationship. The regression coefficients between predicted and measured values were: turbidity (R2 = 0.767); TN (R2 = 0.798,); TP (R2 = 0.907); TSS (R2 = 0.284,) and total algae count (R2 = 0.851). Prediction algorithms are generally best fit to derive water quality parameters. Remote sensing is recommended for frequent and continuous monitoring of Olushandja Dam as it has the ability to provide rapid information on the spatio-temporal variability of surface water quality.
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19

Rahman, Ateeq, Moola M. Nyambe, and Jan-Heiner Küpper. "Namibian algae species: A review of their distribution, medicinal uses and chemical constituents." Journal of Cellular Biotechnology, December 19, 2020, 1–21. http://dx.doi.org/10.3233/jcb-209010.

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The use of indigenous or remote popular knowledge to identify new drugs against diseases or infections is a well-known approach in medicine. The inhabitants of coastal regions in Namibia and other African countries are known to prepare algae extracts for the treatment of disorders and ailments such as wounds, fever and stomach aches, as well as for the prevention of arrhythmia, cancer, and many other diseases. Algae survive in a competitive environment and, therefore, developed defense strategies that have resulted in a significant level of chemical structural diversity in various metabolic pathways. The exploration of these organisms for pharmaceutical, nutritional and medical purposes has provided important chemical candidates for the discovery of new agents against neglected tropical diseases and stimulated the use of sophisticated physical techniques. This current review provides a broad picture on the taxonomy, various medical and nutritional uses of algae, which thus should be of relevance for the African continent and underdeveloped countries in the Global South.
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20

Francois Jakob Jacobs, Olaf Lawrence Friedrich Weyl, Eva Marita Ulvan, Clinton Hay, and Tor Fredrik Naesje. "First observation of fouling of externally attached radio transmitters in an African river." Water SA 46, no. 4 October (October 27, 2020). http://dx.doi.org/10.17159/wsa/2020.v46.i4.9082.

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Fouling of externally attached tags is an important consideration in long-term tagging studies as it may affect fish behaviour and well-being. Two externally attached radio transmitters on African tigerfish Hydrocynus vittatus were covered with short green algae, after the fish were recaptured 49 and 64 days after tagging in the Kavango River, Namibia. This is the first observation of fouling on external radio transmitters from any African river which highlights the importance of conducting studies that evaluate the various health or behavioural effects resulting from tagging.
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21

Janse van Vuuren, Sanet, and Anatoliy Levanets. "First record of Botryococcus braunii Kützing from Namibia." Bothalia 49, no. 1 (January 9, 2019). http://dx.doi.org/10.4102/abc.v49i1.2382.

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Background: Botryococcus braunii is well known from all continents, but it has been sparsely recorded from Africa compared to other continents. The alga recently formed a rusty orange-red bloom in the Tilda Viljoen Dam, situated near Gobabis in Namibia. Blooms of this species are known to produce allelopathic substances that inhibit the growth and diversity of other phytoplankton, zooplankton and fish.Objectives: The objective of this study was to record the presence of B. braunii in Namibia.Method: Morphological features of the species were compared with illustrations and literature on B. braunii found in other continents of the world, particularly North America and Europe. Extensive literature surveys revealed its currently known geographical distribution.Results: The organism responsible for the discolouration of the water was identified as B. braunii. Microscopic examination revealed large colonies that floated in a thick layer on the surface of the water. Literature searches on the geographical distribution of B. braunii revealed that this was the first record of this species’ presence in Namibia.Conclusion: The known geographical distribution of B. braunii was expanded to include Namibia.
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22

Ohde, Thomas. "Investigation of hydrogen sulphide eruptions along the Namibian coastline using different remote sensing systems." Open Geosciences 1, no. 3 (January 1, 2009). http://dx.doi.org/10.2478/v10085-009-0020-9.

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AbstractHydrogen sulphide eruptions with their typical turquoise discolorations at the water surface are a unique phenomenon along the Namibian coastline. The remote sensing techniques of ocean colour sensors and microwave scatterometers were used for the investigation of such events. The studies with ocean colour sensors showed that the turquoise discolorations near the Namibian coast were neither linked to dust deposition into the water column by desert storms nor to the reflection of bright material in shallow water areas. In addition, other coloured marine events like algae blooms and river outflows were differentiable from the hydrogen sulphide eruptions by their special optical properties. Quasi-true colour images and spectral identification methods were utilised to monitor and investigate the spatial and temporal distribution of sulphide events. In the past years, they were sometimes and locally limited discovered. Newest remote sensing observations including our own investigations have established that the occurrence of sulphide events is more frequent and longer lasting. The north-westerly direction of propagation and their velocity between 12 cm s-1 and 15 cm s1 were derived from an event on 14 April 2004. Lastly, the microwave scatterometer remote sensing was applied to investigate the relation of sulphide events to oceanographic conditions. The events from May 2004 were clearly related to strong coastal upwelling.
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