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Yelena V. Likhoshway - One of the best experts on this subject based on the ideXlab platform.
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Effects of water levels on species diversity of silica-scaled chrysophytes in large tributaries of Lake Baikal
Acta Biologica Sibirica, 2020Co-Authors: Anna Yu. Bessudova, L. M. Sorokovikova, I. V. Tomberg, A. D. Firsova, V. N. Sinyukovich, Yelena V. LikhoshwayAbstract:Large tributaries of Lake Baikal considered as a “hotspot” for silica-scaled chrysophytes diversity. Here we presented the updated species composition of silica-scaled chrysophytes and ecological parameters of their habitat in the Barguzin and Selenga River tributaries and delta in a high water level period. The number of registered taxa was significantly lower compared to the low water conditions (23 versus 66 species) and included the following genera with a given number of species: Chrysosphaerella – 1; Paraphysomonas – 2; Clathromonas – 1; Spiniferomonas – 3; Mallomonas – 9; Synura – 7. Mallomonas guttata and Synura borealis were identified in Russian waters for the first time. Thus, the corrected total list of silica-scaled chrysophytes in the Baikal Region includes 79 taxa. Though, the high water level reduced the total number of silica-scaled chrysophyte taxa, it made the water ecosystem more dynamic by enriching it with the entirely new species for this region.
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Biodiversity of silica-scaled chrysophytes in tributaries of northern limit of Lake Baikal
Acta Biologica Sibirica, 2018Co-Authors: Anna Yu. Bessudova, I. V. Tomberg, A. D. Firsova, L. M. Sorokolikova, Yelena V. LikhoshwayAbstract:В устьях рр. Верхняя Ангара и Кичера, а также в трех устьях Ангаро-Кичерской дельты, по которым осуществляется поступление вод в оз. Байкал, – Душкачанском, Среднем и Дагарском в июле 2017 г. проведены комплексные альгологические и гидрохимические исследования. С помощью сканирующей и трансмиссионной электронной микроскопии определен видовой список чешуйчатых хризофитовых, включающий 31 вид и внутривидовой таксон: Chrysosphaerella – 1; Paraphysomonas – 2; Spiniferomonas – 8; Mallomonas – 14; Synura – 6. В результате проведенных исследований список видов чешуйчатых хризофитовых Байкальского региона дополнился 3 таксонами и включает теперь 76 видов и внутривидовых таксонов, что характеризует его как наиболее богатый видами чешуйчатых хризофитовых в мире.
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Silica-Scaled Chrysophytes in Large Tributaries of Lake Baikal
Cryptogamie Algologie, 2018Co-Authors: Anna Yu. Bessudova, L. M. Sorokovikova, I. V. Tomberg, Yelena V. LikhoshwayAbstract:High diversity of silica-scaled chrysophytes was recorded in the Barguzin River mouth and the Selenga River delta. Their flora was represented by 66 species and intra-specific taxa: Chrysosphaerella — 2, Paraphysomonas — 8, Clathromonas — 5, Spiniferomonas — 8, Mallomonas — 29, and Synura — 14. Eight taxa of silica-scaled chrysophytes were observed for the first time in Russia: Chrysosphaerella rotundata, Mallomonas doignonii, M. trummensis, M. corymbosa, Clathromonas poteriophora, Paraphysomonas acuminata acuminata, P. vulgaris, and Synura laticarina. In May, we found scales of Mallomonas striata with morphologically changed structure in the mouth of the Barguzin River and Srednyaya Channel of the Selenga River delta. The flora of silica-scaled chrysophytes studied differs from one tributary to another. We observed only 52 species in the Selenga River delta, whereas in the Barguzin River mouth we identified 35 species. These large rivers affect the flora of Lake Baikal diversifying silica-scaled chrysophytes in its southern and central basins. The total list of species and intra-specific taxa in the Selenga River delta, Barguzin River mouth, and in Lake Baikal includes 72 taxa. Therefore, this area may be considered as a “hotspot” of silica-scaled chrysophytes together with three hotspots observed worldwide earlier.
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Silica-scaled chrysophytes of Lake Baikal
Altay State University, 2017Co-Authors: Yu. A. Bessudova, V. M. Domysheva, A. D. Firsova, Yelena V. LikhoshwayAbstract:The list of silica-scaled chrysophytes of Lake Baikal has been enlarged using electron microscopy. It has been supplemented with 12 species and 2 forms. Spiniferomonas takahashii has been observed for the first time in the water bodies of Russia. According to our data, the list of silica-scaled chrysophytes of Lake Baikal includes 25 species and intra-species taxa: Chrysosphaerella – 3, Paraphysomonas – 2, Clathromonas – 1, Spiniferomonas – 7, Mallomonas – 8 and Synura – 4. We have also analyzed their seasonal dynamics and observed algal species that are dominant in spring, summer and autumn
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The Diversity of Chrysophycean Algae in an Arctic Zone of River and Sea Water Mixing, Russia
American Journal of Plant Sciences, 2015Co-Authors: A. D. Firsova, Anna Yu. Bessudova, L. M. Sorokovikova, I. V. Tomberg, Yelena V. LikhoshwayAbstract:According to the results of studies in the region of lower Yenisei River to the Kara Sea shelf in September 2009, the flora of chrysophyte algae in the zone of river and sea water mixing comprises 43 species of the classes Chrysophyceae and Synurophyceae. Most of them are cosmopolitan and widespread, but four rare species have also been recorded. The most frequent species are Synura petersenii f. petersenii, S. petersenii f. kufferathii, Spiniferomonas takahashii, Mallomonas acaroides, and M. crassisquama. The composition of chrysophyte flora in the study region is similar to that in some lakes of the Taimyr Peninsula. It has been found that the diversity of chrysophytes in the zone of river and sea water mixing depends on water salinity, with a group of species occurring at increased salinity levels. It includes Chrysosphaerella coronacircumspina (5.2‰), Kephyrion spirale (5.2‰) and Mallomonas crassisquama (8‰). These data contribute to knowledge of how the distribution of chrysophytes responds to changes in ecological conditions such as water salinity, turbidity, pH, and concentrations of oxygen and mineral phosphorus.
C. Nalewajko - One of the best experts on this subject based on the ideXlab platform.
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0 1984, by the American Society of Limnology and Oceanography, Inc. Nutrient status of metalimnetic phytoplankton peaks
2015Co-Authors: F. R. Pick, D. R. S. Lean, C. NalewajkoAbstract:The nutrient state of the chrysophyte, Chrysosphaerella longispina, forming a large metalimnetic chlorophyll a peak in Jacks Lake, Ontario, was examined over several summers. Turnover times of phosphate were fast in the epilimnion (minutes) but slow (hours) at the depth of the peak. Long turnover times, high concentrations of polyphosphate, low P debt, low V,,,, and high K, values for phosphorus all indicated that initially the peak was not more P-deficient than epilimnetic phytoplankton. However, with time it became P-deficient and this factor coincided with its demise in August. At no time was the peak population N-deficient. The peak population was not supplied by nutrients from the hypolimnion nor from the mineralization of sedimenting epilimnetic material but instead seemed to have brought cellular reserves of phosphorus when it migrated down from the epilimnion. Several workers have suggested that metalimnetic algal populations are trading off the disadvantages of suboptimal light conditions for the advantages of higher nu
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0 1984, by the American Society of I.imnology and Oceanography, Inc The origin of a metalimnetic chrysophyte peak
2015Co-Authors: F. R. Pick, C. Nalewajko, D. R. S. LeanAbstract:A metalimnetic chlorophyll peak (40-70 pg.liter-*) in Jacks Lake, Ontario, was due primarily to a colonial chrysophyte, Chrysosphaerella longispina. The peak was not the result of in situ growth, nor of a passive and progressive accumulation of epilimnetic cells. Instead, a sudden bloom of the algae which occurred in the epilimnion at the end of June, possibly due to excystment, descended rapidly and within no more than 4 days concentrated in a narrow band below the thermocline. There was no net increase in chlorophyll a or cell biomass with time once the population was established in this region. No dividing cells were observed. After about 2 weeks the Chl a concentration at the peak began to decline and the peak disappeared by the end of August. The importance of metalimnetic peaks is greatly exaggerated by the measurement of Chl a. Subsurface chlorophyll maxima are com-mon in many lakes (Eberly 1959; Ichimur
D. R. S. Lean - One of the best experts on this subject based on the ideXlab platform.
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0 1984, by the American Society of Limnology and Oceanography, Inc. Nutrient status of metalimnetic phytoplankton peaks
2015Co-Authors: F. R. Pick, D. R. S. Lean, C. NalewajkoAbstract:The nutrient state of the chrysophyte, Chrysosphaerella longispina, forming a large metalimnetic chlorophyll a peak in Jacks Lake, Ontario, was examined over several summers. Turnover times of phosphate were fast in the epilimnion (minutes) but slow (hours) at the depth of the peak. Long turnover times, high concentrations of polyphosphate, low P debt, low V,,,, and high K, values for phosphorus all indicated that initially the peak was not more P-deficient than epilimnetic phytoplankton. However, with time it became P-deficient and this factor coincided with its demise in August. At no time was the peak population N-deficient. The peak population was not supplied by nutrients from the hypolimnion nor from the mineralization of sedimenting epilimnetic material but instead seemed to have brought cellular reserves of phosphorus when it migrated down from the epilimnion. Several workers have suggested that metalimnetic algal populations are trading off the disadvantages of suboptimal light conditions for the advantages of higher nu
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0 1984, by the American Society of I.imnology and Oceanography, Inc The origin of a metalimnetic chrysophyte peak
2015Co-Authors: F. R. Pick, C. Nalewajko, D. R. S. LeanAbstract:A metalimnetic chlorophyll peak (40-70 pg.liter-*) in Jacks Lake, Ontario, was due primarily to a colonial chrysophyte, Chrysosphaerella longispina. The peak was not the result of in situ growth, nor of a passive and progressive accumulation of epilimnetic cells. Instead, a sudden bloom of the algae which occurred in the epilimnion at the end of June, possibly due to excystment, descended rapidly and within no more than 4 days concentrated in a narrow band below the thermocline. There was no net increase in chlorophyll a or cell biomass with time once the population was established in this region. No dividing cells were observed. After about 2 weeks the Chl a concentration at the peak began to decline and the peak disappeared by the end of August. The importance of metalimnetic peaks is greatly exaggerated by the measurement of Chl a. Subsurface chlorophyll maxima are com-mon in many lakes (Eberly 1959; Ichimur
F. R. Pick - One of the best experts on this subject based on the ideXlab platform.
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0 1984, by the American Society of Limnology and Oceanography, Inc. Nutrient status of metalimnetic phytoplankton peaks
2015Co-Authors: F. R. Pick, D. R. S. Lean, C. NalewajkoAbstract:The nutrient state of the chrysophyte, Chrysosphaerella longispina, forming a large metalimnetic chlorophyll a peak in Jacks Lake, Ontario, was examined over several summers. Turnover times of phosphate were fast in the epilimnion (minutes) but slow (hours) at the depth of the peak. Long turnover times, high concentrations of polyphosphate, low P debt, low V,,,, and high K, values for phosphorus all indicated that initially the peak was not more P-deficient than epilimnetic phytoplankton. However, with time it became P-deficient and this factor coincided with its demise in August. At no time was the peak population N-deficient. The peak population was not supplied by nutrients from the hypolimnion nor from the mineralization of sedimenting epilimnetic material but instead seemed to have brought cellular reserves of phosphorus when it migrated down from the epilimnion. Several workers have suggested that metalimnetic algal populations are trading off the disadvantages of suboptimal light conditions for the advantages of higher nu
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0 1984, by the American Society of I.imnology and Oceanography, Inc The origin of a metalimnetic chrysophyte peak
2015Co-Authors: F. R. Pick, C. Nalewajko, D. R. S. LeanAbstract:A metalimnetic chlorophyll peak (40-70 pg.liter-*) in Jacks Lake, Ontario, was due primarily to a colonial chrysophyte, Chrysosphaerella longispina. The peak was not the result of in situ growth, nor of a passive and progressive accumulation of epilimnetic cells. Instead, a sudden bloom of the algae which occurred in the epilimnion at the end of June, possibly due to excystment, descended rapidly and within no more than 4 days concentrated in a narrow band below the thermocline. There was no net increase in chlorophyll a or cell biomass with time once the population was established in this region. No dividing cells were observed. After about 2 weeks the Chl a concentration at the peak began to decline and the peak disappeared by the end of August. The importance of metalimnetic peaks is greatly exaggerated by the measurement of Chl a. Subsurface chlorophyll maxima are com-mon in many lakes (Eberly 1959; Ichimur
De Wujek - One of the best experts on this subject based on the ideXlab platform.
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Silica-scaled Chrysophyceae and Synurophyceae from Nigeria. III. Chrysophytes from rivers of Edo State
Fottea, 2010Co-Authors: De Wujek, Margaret Osikhofe Kadiri, Ryan M. DziedzicAbstract:A total of 18 species of silica-scaled chrysophytes (Chrysophyceae: one species each in Chrysosphaerella, Spiniferomonas, and Paraphysomonas; Synurophyceae: 11 Mallomonas spp. and four Synura spp.) was recorded from river samples collected in Edo State, Benin, Nigeria, from both dry and rainy seasons in 2003. Identifications were based on transmission electron microscopy. Five are new records for Nigeria, including four being newly reported for Africa. Two further species could not be identified.
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Silica-scaled chrysophytes from east central New York
The Journal of the Torrey Botanical Society, 2006Co-Authors: De Wujek, Evan M. Wright, Francis J. MenapaceAbstract:Abstract Forty-three scaled chrysophytes (Synurophyceae: 26 Mallomonas spp., nine Synura spp.; Chrysophyceae: three Chrysosphaerella and Spiniferomonas spp., and two Paraphysomonas spp.) in 41 water samples from Columbia, Franklin, Hamilton, Herkimer, Otsego and St. Lawrence Counties, New York, were identified using TEM. Fourteen taxa are new records from New York, including one new report for the U.S. Temperature, pH, and conductivity ranges of the prevalent species are discussed. Non-siliceous scales of two colorless free-living flagellates, Gyromitus disomatus, an organism of uncertain taxonomic affinity, and the organic scaled chrysophyte-like Pseudodendromonas vlkii, were also observed.
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Silica-scaled chrysophytes and synurophytes from East Texas
Texas Journal of Science, 2002Co-Authors: De Wujek, James L Wee, James E. Van KleyAbstract:A total of 27 scale-bearing species of the algal classes Chrysophyceae and Synurophyceae, referred to herein as scaled chrysophytes, were recorded in 35 water bodies from 11 eastern Texas counties using transmission electron microscopy. These were distributed between the Chrysophyceae (one Chrysosphaerella sp., one Paraphysomonas sp. and two Spiniferomonas sp.) and Synurophyceae (14 Mallomonas sp. and nine Synura sp.). The number of taxa per collection varied from zero to six. Twenty-three taxa are new records for Texas. Mallomonas multisetigera is reported for the first time from North America. Scales of the colorless free-living flagellate Gyromitus disomatus, an organism of uncertain taxonomic affinity, were also observed.