Ulothrix Zonata Research Articles

Phycoremediation of crude oil polluted water from selected water sources in Ogoniland, Rivers State, Nigeria.

Crude oil exploitation in the Niger Delta, particularly in Ogoniland, brought environmental devastation occasioned by petroleum pollution, as farmlands and water sources were destroyed. This study was designed to remediate crude oil contaminated water obtained from water sources in Ogoniland using two green algal species. Thirty water samples were collected from eight different water sources. The samples were analysed for total petroleum hydrocarbon (TPH) using gas chromatography/flame ionization detector (GC/FID). Algal samples were collected from Ogba River and at wetland in Military Hospital Benin, Edo State, Nigeria. The algal samples were identified, screened, optimized and grown in Bold basal medium. Results obtained from the determination of TPH showed that the infiltrated pond (Exc) sample site had the highest concentration among all the sites sampled with 198.8329 μg/L, R2 with 134.1296 μg/L, R1 with 108.9394 μg/L, R3 with 105.8011 μg/L, R4 with 98.442 8 μg/L, the hand-dug wells (Wll) had 9.6586 μg/L while the borehole (Bhl) had the lowest with 1.8310 μg/L. It was deduced that pollution of water sources was principally because of pollutants washed from the soil environment into the open surface water sources via run-off rather than through the seepage from the underground aquifers, incriminating illegal oil mining and artisanal refining. Results obtained from the analysis of algal growth medium indicated that the two algal species were able to absorb the hydrocarbon contaminants, albeit at different rates, corresponding with the algal growth rate. Analysis of algal biomass after 4 weeks of remediation showed that from the initial 10.27 μg/20 mL added to the growth medium, the highest TPH mean value of 0.490 μg/20 mL was extracted from Ulothrix zonata (F.Weber & Mohr) Kützing biomass grown in Exc compared to 0.344 μg/20 mL of TPH extracted from Chlorella sorokiniana Shihira & R.W.Krauss grown in the same sample site. Also, Ulothrix zonata had higher TPH yield 0.023 μg/20 mL in Bhl compared to Chlorella sorokiniana 0.021 μg/20 mL of TPH from the same water source. This result indicated Ulothrix zonata had superior TPH phycoremediation ability to Chlorella sorokiniana. While the present study calls for deployment of the algal species for field trial, it is strongly recommended that crude oil pollution should be discouraged.

NEW DATA ON THE COMPOSITION OF CYANOBACTERIA AND ALGAE OF SOME WATERCOURSES OF THE KAMCHATKA PENINSULA

The results of studying the biological diversity of the fl ora of freshwater algae in some streams of the Kamchatka Peninsula are presented, the structure of algal periphyton communities is revealed and the ecological characteristics of the studied algofl ora are given. The following rivers were surveyed: Kamchatka, Andrianovka, Plotnikova, Avacha, Paratunka, Gavanka, Kirpichnaya, Karymshina, Mutnushka and the Perviy stream. As a result of sample processing, 193 species, varieties and forms of cyanobacteria and algae from fi ve divisions were found: Cyanobacteria – 5 species, Bacillariophyta – 167 taxa (taking into account varieties and forms – 177), Ochrophyta – 2, Charophyta – 4, Chlorophyta – 5. In the algae communities of the surveyed water bodies, both in terms of abundance in fouling and species diversity, diatoms prevailed. The most common species, often growing on stones and dominating in fouling, were Encyonema minutum, E. silesiacum, Hannaea arcus, Gomphonema ventricosum, Ulnaria inaequalis, Cocconeis placentula, Fragilaria capucina, Nitzschia palea. Melosira varians, Meridion circulare, Planothidium lanceolatum, Gomphonella olivacea, species of the genera Staurosira, Diatoma, Cymbella, Fragilaria and some others were most often present as subdominants. In some cases, Rhoicosphenia abbreviata, Didymosphenia geminata, and Tabularia fasciculata took the fi rst places in terms of abundance. Of the Chlorophyta Ulothrix zonata and Cladophora glomerata were found. In a number of streams Hydrurus foetidus was encountered in mass. The division of Charophyta is represented by fi laments of Spirogyra and single specimens of the genera Closterium and Cosmarium. Cyanobacteria practically did not form mass fouling, except for the Tapinothrix genus. For each surveyed area, the species composition of algae was determined and complexes of dominant species were characterized. Giving a general ecological characteristic of the studied algofl ora, it should be noted that benthic and planktonic- benthic organisms predominate in periphyton communities, which are indiff erent to water salinity and prefer a slightly alkaline habitat.

Cytomorphology of the wound healing process in the green filamentous algae, Ulothrix zonata (F. Weber & Mohr) K tzing 1833

Abstract. For the first time, we present a cytomorphological description of the self-healing (repair) process of damaged thalli sites, wound healing , in the green filamentous algae, Ulothrix zonata (F. Weber & Mohr) K tzing 1833. In the filaments of this species from Lake Baikal and the Angara (Baikal outflow), Zhilishche (Baikal inflow) and Ida (Angara inflow) rivers, light microscopy methods revealed dome-like and conical protrusions and elongations of transverse cell walls directed into adjacent dead (without protoplast) and defective (with deformed chloroplasts) cells. At the same time, there were mostly patterns where two cells formed protrusions directed into the same damaged filament site between them, i.e. towards each other. The growth of previously unconnected cells towards each other led to their convergence and adjacency. This had two important physiological consequences that ensured the restoration of the filament integrity. The first consequence was the formation of intercellular junctions. The second one was the fusion of the protoplasts and nuclei of the adjacent cells (cell fusion) with the formation of vegetative polyploid cells with increased size. During subsequent divisions of these cells, extended areas emerged with a two- to three-fold increase in the diameter of the algal filaments. It was also found that the process of wound healing promoted the development of giant hypnospores. We showed that the H-shaped septa between cells of filamentous algae were not thickenings of the outer walls but the sheaths of the dead cells preserved after this reparation process. Analysis of the wound healing patterns revealed that the Ulothrix cell nuclei did not migrate to the polarized regions of the cells but retained their central position, which testifies to their fixation in the protoplast. We observed sporadic cases of the development of lateral filaments in U. zonata were due to the self-repair of defective cells and their subsequent division during wound healing . A comparison of various cell deformations allowed us to determine the characteristic stages of the wound healing process in U. zonata, which have some similarities and differences with those in marine red filamentous algae. Our study indicates that wound healing is an evolutionarily developed and genetically programmed adaptation that may be widespread in the population of filamentous algae.

Phytoplankton diversity in relation to physicochemical attributes and water quality of Mandakini River, Garhwal Himalaya.

Phytoplankton are important biological indicators of water quality. This current study assessed the physicochemical parameters and phytoplankton diversity of Mandakini River, an important tributary of the River Ganga. Water and phytoplankton samples were collected from three sampling sites located at three different altitudes for a period of twelve months (July 2018-June 2019). Water samples were analyzed for fourteen important physicochemical parameters along with the identification of phytoplankton by following the standard methodology. A total of 21 species of phytoplankton under three major groups Bacillariophyceae (Cymbella aequalis, Diatoma vulgaris, Fragilaria arcus, Frustulia rhomboids, Gomphonema geminatum, Navicula confervacea, Nitzchia diversa, and Synedra ulna); Chlorophyceae (Volvox sp., Cladophora glomerata, Closterium longissima, Hydrodictyon sp., Microspora amoena, Spirogyra sp., Oedogonium sp., Ulothrix zonata, and Zygnema cylindrospermum); and Cyanophyceae (Anabaena ambigua, Chlorococcum humicola, Nodularia sp., and Oscillatoria sancta) were observed and recorded during the study period. Site S3 (Rudraprayag) had the highest species diversity. From this study, the effect of physicochemical parameters on the diversity and density of phytoplankton was observed. It also includes the overall significance of phytoplankton and physicochemical parameters to the water quality of the Mandakini River along with the key factors that were responsible for the degradation of water quality. The current study also provides baseline information to future researchers working in a similar discipline.

Characteristics of effluents from trout farms and their impact on water quality and benthic algal assemblages of the receiving stream

In this study, characteristics of effluents from three flow-through rainbow trout farms in Turkey and their impact on water quality and epilithic algal communities of the receiving stream were investigated. Water samples were taken monthly from both inlets and outlets of three fish farms, while both water and epilithic algae samples were collected from two stations (upstream and downstream) in the stream. A significant increase from inlets to outlets was observed for chemical oxygen demand (COD), soluble reactive phosphorus (SRP), total suspended solids (TSS), NH4–N and total phosphorus (TP) (p < 0.05) due to no effluent treatment processes and high FCR at the fish farms. The daily average total nitrogen (TN) and TP fluxes of the fish farms predicted with the nutritional method were found close to those measured with the hydrological method. Although there were significant increases in COD, TSS, NH4–N, TN, NO3–N, NO2–N, TP and SRP concentrations at the downstream station compared to the upstream station of the receiving stream (p < 0.05), water quality of the downstream station remained in Class I in terms of examined parameters. Trophic Diatomic Index and Biological Diatom Index values indicated that the upstream station had a better water quality than the downstream station. Also, filamentous algae such as Cladophora glomerata, Ulothrix zonata and Stigeoclonium lubricum were observed at the downstream station. In view of the above findings, several suggestions were put forward to protect the water quality of the receiving stream.

Microalgal structure and diversity in some canals near garbage dumps of Bobongo basin in the city of Douala, Cameroun

Anarchical and galloping anthropization is increasingly degrading the wetlands. This study aimed at determining the structure, diversity and spatiotemporal variation of microalgae from a few canals in the vicinity of garbage dumps of the Bobongo basin to propose methods of ecological management of these risk areas. Sampling took place from March 2016 to April 2019. Pelagic algae as well as those attached to stones and macrophytes were sampled in 25 stations. These algae samples were brought back to laboratory for identification and counting. The specific richness amounts to 13 classes, 34 orders, 52 families, 69 genera and 116 species. The dominant class is that of Bacillariophyceae (33 species) with a proportion of 28.45%. Results based on correspondence factor analysis revealed 3 groups of stations (clusters): the group I from stations 16, 21 and 25 consisted of exclusive species such as Cyclotella ocellata, Cymbella gamma, Gomphosphaeria natans, Navicula cryptocephalla and Tabellaria flocculosa. Group II from stations 18, 22, 23 and 24 consisted of exclusive species such as Aphanizomenon flosaquae, Aphanocapsa holsatica, Astasia limpida and Ulothrix zonata. Group III was made up of species common to all stations. Cyclotella ocellata, Cymbella gamma, Gomphosphaerium natans, Navicula cryptocephalla and Tabellaria flocculosa are hydrocarbon-polluting species. Our analysis is, to our knowledge, the first demonstrate the use of microalgal species as indicators of pollution in the context of environmental management for better monitoring of the quality of watercourses. In addition, these species can be used as bio-purifiers of polluted water in hydrocarbon.

Algal growth in an irrigation canal and its effect on flow function

In the A irrigation district in Yamagata Prefecture, Japan, a rehabilitation project is being implemented due to the aging of the irrigation facilities; 40 years have elapsed since the previous project was conducted. An overflow due to a rise in the canal water level occurred in early May of 2016. An increase in the roughness coefficient caused by algal growth in the canal was thought to be one of the reasons for this overflow. Therefore, the relationship between algal growth and the roughness coefficient in an 11-km section of the canal was analyzed in this study. The objectives of this study were to: (1) clarify the changes in the roughness coefficient associated with the growth of algae; (2) identify the dominant algae in the canal and examine the relationships between the growth/decline of algae and water temperature and sunshine; (3) determine the effectiveness of fiberglass reinforced plastic mortar (FRPM) panels constructed in an attempt to suppress algal growth; and (4) clarify why overflow occurred in 2016 but did not occur again in 2017. Ten algae observation points and four flow velocity measurement points were selected in the target section of the canal. Algae observations and flow velocity measurements were carried out once a week in the irrigation season in 2017. This study found that: (1) the roughness coefficient varied from 0.011 to 0.019 and increased with the growth of algae; (2) the major algae identified in the canal were Ulothrix zonata, Hydrurus foetidus, and microscopic diatoms, and since all of these are cold-water algae they started declining when the water temperature was over 13 °C; (3) the FRPM panels suppressed the growth of U. zonata and suppressed increases in the roughness coefficient; and (4) the main reason for the overflow from the canal in 2016 was that the period suitable for algal growth was longer in 2016 than that in 2017 due to irrigation beginning 10 days earlier in 2016 than in 2017.

Element Composition and Biogeochemical Functions of Algae Ulothrix Zonata (F. Weber et Mohr) Kützing in the Coastal Zone of the Southern Baikal

ICP-MS method was used to study the element composition of green algae Ulothrix zonata (F. Weber et Mohr) Kutzing, sampled in the coastal zone of the Southern Baikal. Dominating in Ulothrix composition are S, Ca, P, Mg and microelements Fe, Al, Ti, Mn, Sr, Ba, Cu, Zn, La, Ce, As, Br, and Pb. The concentrations of all analyzed elements in alga thallomes is greater than the respective concentrations in coastal zone water. The dry mass of U. zonata accumulates more P, As, S, I, Br, Ni, Cd, Ca, and Mg than the stone substrate does. The effect of U. zonata on the formation of element composition of water medium in the coastal zone is demonstrated.

Improving phylogenetic inference of core Chlorophyta using chloroplast sequences with strong phylogenetic signals and heterogeneous models

Phylogenetic relationships within the green algal phylum Chlorophyta have proven difficult to resolve. The core Chlorophyta include Chlorophyceae, Ulvophyceae, Trebouxiophyceae, Pedinophyceae and Chlorodendrophyceae, but the relationships among these classes remain unresolved and the monophyly of Ulvophyceae and Trebouxiophyceae are highly controversial. We analyzed a dataset of 101 green algal species and 73 protein-coding genes sampled from complete and partial chloroplast genomes, including six newly sequenced ulvophyte genomes (Blidingia minima NIES-1837, Ulothrix zonata, Halochlorococcum sp. NIES-1838, Scotinosphaera sp. NIES-154, Caulerpa brownii and Cephaleuros sp. HZ-2017). We applied the Tree Certainty (TC) score to quantify the level of incongruence between phylogenetic trees in chloroplast genomic datasets, and show that the conflicting phylogenetic trees of core Chlorophyta stem from the most GC-heterogeneous sites. With removing the most GC-heterogeneous sites, our chloroplast phylogenomic analyses using heterogeneous models consistently support monophyly of the Chlorophyceae and of the Trebouxiophyceae, but the Ulvophyceae was resolved as polyphyletic. Our analytical framework provides an efficient approach to reconstruct the optimal phylogenetic relationships by minimizing conflicting signals.

Isolation, Purification and Identification of Seven species of Algae in three drinking water plants supply springs in Sulaimani province and growth control of isolated algae by using some plant extracts

In this study, three drinking water treatment plant supply springs were selected within different sites in Sulaimani province - Kurdistan region of Iraq. Samples were collected over period of eight months from May to the end of December 2015.&#x0D; Five stations were selected, Stations 1, 2 and 3 were located at Bestan Sowr drinking water project in Sharazur district, station 4 was located at Saray Subhan Agha drinking water project in Said sadiq district and station 5 was located at Khurmal drinking water project in Khurmal district within Halabja district.&#x0D; The study involved an Isolation, purification and identification seven species of algae by using Chu-10 media and Bold Basal Medium (BBM), and evaluation of the effectiveness of plant extracts (as antialgal) on the growth of isolated algae by Agar-Well Diffusion Method.&#x0D; Seven strains of algae from studying stations were isolated, purified and identified after collection which were: Ulothrix zonata, Desmodesmus lunatus, Desmodesmus itascaensis, Chlorella vulgaris, Calothrix fusca, Chroococcus turgidus and Navicula riediana. These isolated algae included 2 species of blue-green algae, 4 species of green algae, and 1 species of diatoms.&#x0D; In this study, the suggested plants extracts for use as inhibitors belong to different families of plant (5 plants) which were Hordeum vulgare (Barley straw), Peganum harmala, Artemisia annua, Thymus vulgaris and Nasturtium officinale (Watercress).&#x0D; On the assessment of the effectiveness of crude plant extracts (as antialgal) on the growth of selected algae by Agar-Well Diffusion Method, the results showed that the greater inhibition zone diameter was obtained 62 mm against Calothrix fusca by using crude extracted from Peganum harmala in concentration 80 mg/ml, and less inhibition zone diameter was 7 mm against Ulothrix zonata by using crud extracted from Artemisia annua in concentration 30 mg/ml. Nasturtium officinale (Watercress) did not show any effective against any type of isolated algae in all concentrations. Generally inhibition zones diameters differed according to the algal types and types and concentration of plant’s extracts.

Proteins homologous to aquaporins of higher plants in the freshwater alga Ulothrix zonata (Ulotrichales, Chlorophyta)

The green filamentous alga Ulothrix zonata inhabits Lake Baikal and overgrows the underside of hummocky ice during winter and spring. To clarify physiological adaptations of U. zonata to low temperature and the potential contribution of membrane water permeabilities, the expression level of aquaporins from a winter population growing under the lake ice and in interstitial water was compared with that of benthic summer and autumn populations of algae by immuno-detection using an anti-maize PIP1 (plasma membrane intrinsic protein) antiserum. Algal, and in particular Ulvophycean, transcriptome sequences are only partially available and this higher plant-specific PIP1 epitope has not been detected so far in available genomic datasets. PIP1 expression levels were highest in the ice population and the rise in water temperature during summer was correlated with a drop in PIP1 amounts, which slightly increased again in autumn. ITS2 rDNA (internally transcribed spacer region 2) sequences revealed conspecificity of the ice and summer populations. The difference in PIP1 aquaporin expression suggests adaptation of the algae to changing environments by maintaining membrane permeability at low temperatures. Our study shows that the ice population of U. zonata inhabiting Lake Baikal is a unique subject for studying physiological and biochemical adaptation mechanisms of freshwater extremophiles.

Identification of filamentous green algae from an area of local biogenic pollution of Lake Baikal (Listvennichnyi Bay) using SSU 18S rDNA

A local eutrophication process is noted for the first time in Listvennichnyi Bay in Lake Baikal. Using morphological and molecular-genetic methods, species of filamentous green algae that form mats at site of the lake subjected to anthropogenic impact are identified. The presence of species of the genus Spirogyra Link., atypical for this part of the lake, as well as their distribution, together with species Ulothrix zonata (Web. et Mohr) Kurz. in an atypically large depth, indicates the serious disturbance of the structure of plant community of the studied site of Baikal.

Nearshore benthic blooms of filamentous green algae in Lake Baikal

For the first time, species of the genus Spirogyra, non-typical of the open nearshore waters of Lake Baikal, formed algal mats with Ulothrix zonata, Ulothrix tenerrima, and Ulothrix tenuissima near the village of Listvyanka, Russia. Normally widely distributed in the 0- to 1.5-m depth range, the growth of U. zonata was now evident and dominant (63% of the biomass) in the 2- to 5-m depth range. The overgrowth of the lake bottom by filamentous green algae, changes in distributional boundaries, the emergence and mass development of species of the genus Spirogyra, the presence of the eutrophic diatom indicator Fragilaria capucina var. vaucheriae, elevated abundances of coliform bacteria, and elevated levels of nutrients suggest an early stage of cultural eutrophication in the nearshore of Lake Baikal near Listvyanka, a popular tourist destination. The unusual abundance of Fragilaria associated with the filamentous green algae consisted of long-ribbon colonies of F. capucina var. vaucheriae, a eutrophic species, wound around the filamentous green algae, enhancing the dense algae mats. Historically dominant species, such as Didymosphenia geminata, Tetraspora cylindrica var. bullosa, and Draparnaldioides baicalensis typically observed at deeper depths of Lake Baikal, are now subdominants or minor species in the nearshore along the shoreline near Listvyanka.

Background Concentrations of Heavy Metals in Benthos from Transboundary Rivers of the Transbaikalia Region, Russia

The concentrations (mg/kg dry weight) of Cu, Zn, As, Cd, Hg, and Pb were measured in benthic macroalgae and invertebrates collected in the upper transboundary tributaries of the Onon River, Transbaikalia, Russia. The background concentration ranges in Cladophora fracta, Ulothrix zonata and Zygnemataceae were: 6.4-9.1 for Cu, 27.2-73.1 for Zn, 0.4-0.9 for Cd, 6.7-35.3 for As, 0.01-0.02 for Hg, and 1.9-4.3 for Pb. In Brachycentrus americanus and Lymnaea media the concentration ranges were: 9.0-25.5 for Cu, 21.4-96.0 for Zn, 0.1-0.3 for Cd, 1.7-5.6 for As, 0.004-0.02 for Hg, and 0.4-2.2 for Pb. The concentrations of Cu, Zn, Pb, and Hg were consistent with data for uncontaminated areas. Under contamination conditions the concentrations in C. fracta were: 938 for Zn, 513 for Pb, and 9.5 for Cd; in Lymnaea media were: 46.8 for Cu, 176 for Zn, 52.3 for Pb, and 3.0 for Cd. All the organisms showed a common response to contamination, and consequently can be used as biomonitors of contamination by heavy metals.

Identification of filamentous green algae from an area of local biogenic pollution of Lake Baikal (Listvennichnyy bay) using SSU 18S rDNA molecular marker

Background. A local eutrophication process is noted for the first time in Listvennichnyi bay in Lake Baikal. High level of biogenic elements in the water of the bay led to nuisance growth of filamentous algae. Rapid identification of these algae's taxa was necessary to assess ecosystem damage in the polluted area of the lake. Materials and methods. We determined a boundary of bottom fouling by locating transects ranging from 0 to 10 meters in different areas of the bay. Algae samples were examined using microscopic techniques as well as SSU 18S rDNA sequencing. Phylogenetic trees were estimated using Bayesian inference (BI) based on SSU alignment. Results. Our results showed intensive filamentous algae fouling in depth from 3 to 10 meters along the coastline of the eastern part of the bay. Morphological and molecular analysis demonstrated prevalence in samples of Ulothrix zonata (Web. et Mohr) Kütz. Using SSU 18S rDNA sequencing data we also showed presence of three species of Spirogyra Link. genus. Conclusion. Detection of Spirogyra species which are normally not typical for such areas of the lake along with Ulothrix zonata extended more deeply than usually observed reveals severe phytocenosis disturbance of the polluted part of Lake Baikal.

Seasonal variations of metal concentrations in periphyton and taxonomic composition of the algal community at a Yenisei River littoral site

AbstractThe concentrations of metals K, Na, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Pb, Co and Cr, in the water and periphyton (epilithic algal communities) were studied at a site in the middle stream of the Yenisei River (Siberia, Russia) during three years using monthly sampling frequencies. Despite considerable seasonal variations in aquatic concentrations of some metals, there was no correlation between metal contents in the water and in periphyton. Seasonal concentration variations of some metals in periphyton were related to the species (taxonomic) composition of periphytic microalgae and cyanobacteria. Enhanced levels of Ni and Co in periphyton in late autumn, winter, and early spring were likely caused by the predominance of cyanobacteria in the periphytic community, and annual maximum levels of K in periphyton in late spring and early summer were attributed to the domination of Chlorophyta, primarily Ulothrix zonata.

Temporal variation in fatty acid composition of Ulothrix zonata (Chlorophyta) from ice and benthic communities of Lake Baikal

S. Osipova, L. Dudareva, N. Bondarenko, A. Nasarova, N. Sokolova, L. Obolkina, O. Glyzina and Oleg Timoshkin. 2009. Temporal variation in fatty acid composition of Ulothrix zonata (Chlorophyta) from ice and benthic communities of Lake Baikal. Phycologia 48: 130–135. DOI: 10.2216/08-49Fatty acid (FA) composition of total lipids was compared between populations of the freshwater alga Ulothrix zonata growing in the interstitial water of the ultrapure ice cover of Lake Baikal in early spring (ice population) and on the shallow stony bottom of the lake during the ice-free season (benthic population). FA content was analysed by chromatographic mass spectrometry. Our observations over two years indicated that the FA profiles of both Baikalian ice and benthic populations of U. zonata, as are typical for other green algae, showed a high level of polyunsaturated FAs (50–70% depending on season) related to the adaptation of the alga to low temperature. Rising temperature in the algal habitat entailed a prominent drop in the proportion of monoenoic cis-7-hexadecenoic acid (from 0.8% to 3.5% in 2006). These results favour the hypothesis that monoenoic FAs play a principal role in maintaining the cellular membrane fluidity of U. zonata.

경기도내 5기 석조문화재의 기중조류의 분포와 조류 서식 등급

We have conducted the study of distribution and inhabitation of the aerial algae from five stone cultural properties located in Gyeonggi-do. A total of 21 taxa were identified, among which 8 taxa of cyanophytes, 12 taxa of cholorophytes and one diatom species. Protococcus viridis, Ulothrix zonata, Synechocystis aquatilis and Chroococcus varius occurred in 15, 9, 8 and 7 study sites, respectively. These coccoid types appeared more frequently than filamentous types. In this study, Chlorococcum infusionum, Cylindrocystis gracilis, Klebsormidium crenulatum, Klebsormidium dissectum and Klebsormidium flaccidium newly recorded from Korea. We found that 80% of stone cultural properties had aerial algae and their 58-84% were grouped into Class 5 based on chlorophyll-a concentration.ጊ漀Ѐ㔴〻Ԁ䭃䑎䷙᜕ష6㘴⸸㬅K䍄乍숗ᜎ꜀ࠀ㘶㐮〲㠻Ԁ䭃䑎䴀

Green algae as a structural element of phytoperiphyton communities in streams of NW Russia

Observations were made on the development and distribution of phytoperiphyton communities in 66 lake-river systems in NW Russia from Lake Ladoga to the Barents Sea. In total, 130 genera and 648 species were identified from different substrates, belonging to Cyanophyta (19.1%), Bacillariophyta (59.6%), Chlorophyta (18.7%), and algae from other orders (2.6%). In all streams diatoms dominated by species richness, but they were surpassed by green algae in terms of biomass. The green algae ranged from small planktonic forms to large filamentous species and produced easily visible algal communities. Among the planktonic forms the desmids were the most diverse group. They occurred in attached communities of all rivers and, while never abundant, were widespread. The attached community’s biomass was dominated by green algae. Among these, the filamentous algae Mougeotia sp., Oedogonium sp., Zygnema sp., Spirogyra sp. and Ulothrix zonata exhibited mass development in streams. Their distribution was patchy in the basin, with a total cover varying from less than 1% to 90% of the stream bottom. In some river stretches the diversity and predominance of green algae could be due, in part, to poorly developed riparian canopies.

The influence of a toxic cyanobacterial bloom and water hydrology on algal populations and macroinvertebrate abundance in the upper littoral zone of Lake Krugersdrift, South Africa

The biological interactions and the physical and chemical properties of the littoral zone of Lake Krugersdrift were studied for a 4-month period when a dense, toxic cyanobacterial bloom dominated by Microcystis aeruginosa was present in the main lake basin. The presence of a toxic strain of M. aeruginosa was confirmed through the use of ELISA and molecular markers that detect the presence of the mcyB and mcyD genes of the mcy gene cluster that synthesizes microcystin. An increase in Microcystis toxicity at sites dominated by the cyanobacterial scum was accompanied by an increase in total abundance of the macroinvertebrate families Hirudinae, Chironomidae, and Tubificidae. Sites located away from the cyanobacterial scum had a lower abundance but a higher diversity of macroinvertebrates. The water quality under the Microcystis scum was characterized by low pH values, low concentrations of dissolved oxygen, and lower total alkalinity values. The periphytic alga Ulothrix zonata was absent in areas dominated by the cyanobacterial scum, possibly as a result of overshadowing by the scum or direct toxic allelopathic effects on growth and photosynthesis. The diatom Diatoma vulgare dominated the benthic algal flora beneath the cyanobacterial scum.