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  • Author: Jūratė Kasperovičienė x
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Abstract

Karosienė J., Kasperovičienė J., 2012: Peculiarities of epiphyton algal communities formation on different macrophyte species [Skirtingų makrofitų rūšių epifitono dumblių bendrijų formavimosi ypatumai]. - Bot. Lith., 18(2): 154-163.

The epiphyton on different aquatic vegetation represented by emerged macrophytes (Phragmites australis, Equisetum fluviatile, Schoenoplectus lacustris), floating-leaved plants (Nuphar luteum) and submerged macrophytes (Potamogeton perfoliatus, Chara rudis) was studied in two meso- and mesoeutrophic lakes. The morphological characteristics, physiological and synecological peculiarities of plant host had more effect on epiphyton algae abundance and biomass than species richness. The highest densities of algae were associated with helophytes Phragmites australis, Equisetum fluviatile, the lowest was recorded on Schoenoplectus lacustris and laminae of Nuphar luteum. Loosely attached diatoms prevailed on helophytes, adnate species on Nuphar luteum laminae. Cyanobacteria and green algae were more abundant on Nuphar luteum laminae and Potamogeton perfoliatus.

Abstract

The current study summarised the diversity of cyanobacteria found in various habitats of the second largest raised bog of Lithuania. A total of 56 cyanobacteria species that comprise 19% of all phycoflora diversity in Kamanos raised bog were recorded. Species from the Chroococcales (32 species) order and the Chroococcus (7), Aphanothece (7) genera were the most numerous. Twenty one cyanobacteria species were found in Lithuania for the first time. Most of species recorded in Kamanos raised bog were cosmopolite or distributed in temperate zone. One third of the species were characteristic particularly of the peat bogs. Thirty nine species of cyanobacteria were specific to the particular water body and occurred only in 1–3 of the studied localities. Only five species, i.e. Chroococcus turgidus, Aphanocapsa grevillei, Aphanothece elabens, Cyanosarcina sp. and Hapalosiphon sp. were common. Peculiarities of the habitat were the most important drivers determining species richness and composition of cyanobacteria in a particular locality.

Abstract

Koreivienė J., Belous O., Kasperovičienė J., 2012: Variations of microcystins in freshwater ecosystems [Mikrocystinai gėlavandenėse ekosistemose]. - Bot. Lith., 19(2): 139-148 Increased frequency, severity of harmful algae blooms and their extent worldwide have become a global challenge due to the production of toxins that are released to the water. Cyanotoxins are detected in 25-75% of blooms. Hazardous hepatotoxin-microcystin potential producers, spatial and temporal variations of toxins as well as their variations depending on environmental variables are discussed in this overview. The most common species among microcystin producers belong to the genera Dolichospermum and Microcystis. Variations of the amount of microcystins detected through the bloom are associated with the dominant cyanobacteria species or its genotype. The abundance of toxic cyanobacteria genotype and cyanotoxin values increase with the rise of water temperature and nutrient concentrations in the freshwaters. On the seasonal basis, cell-bound microcystin concentrations increase with bloom development, whereas extracellular cyanotoxin values rise with the senescing of bloom after cyanobacterial cell lysis.

Abstract

A total of 23 new to Lithuania cyanobacteria species were recorded in phytobenthos of 70 rivers in 2009–2011. New species belong to the Chroococcales and Oscillatoriales orders, 10 families and 12 genera. Descriptions of species morphology and original photos are presented; cyanobacteria’s ecological groups and distributions are analysed. The paper contains information about the possibility of employment of new species as indicators for the assessment of ecological status of Lithuanian rivers.

Abstract

In Kamanos raised bog, the green algae community was represented by 160 taxa distributed into eight Chlorophyceae orders. The diversity of desmids (93 taxa) that are an essential algal component of raised bogs was most relevant. Chlorococcales comprised 30 taxa and Ulotrichales – 15 taxa. Representatives from the rest green algae groups were scarce. Higher variety of habitats in Lake Kamanos and the pools supported more diverse flora of green algae (151 taxa) compared to black hollows (61 taxa). Actinotaenium cucurbita was the single species found in all studied water bodies of Kamanos raised bog. Characium ornitocephalum, Asterococcus superbus, Cosmarium amoenum, Micrasterias truncata, Spondylosium pulchellum, Netrium digitus were found in the lake and all pools, whereas Cosmoastrum scabrum, Tetmemorus laevis – in all hollows. In the current study, the composition of desmid taxa recorded in Kamanos raised bog in two research periods was compared. The first reports on desmids were published by , . He found 129 Desmidiales (18 genera) and 10 Zygnematales species (4 genera). Fifty five species identified by V. Vilkaitis were found repeatedly during the current investigation. In 2005, 42 species were newly recoded in Kamanos raised bog, and of these, 17 taxa were new to desmid flora of Lithuania. A numerous rare species recorded by were not observed repeatedly probably due to long-term changes that had occurred in the peat bog and not enough comprehensive study that represented only part of Kamanos wetland. Some new rare desmid species (e.g. Micrasterias jenneri, Cosmarium cymatonotophorum, Desmidium cylindricum, Actinotaenium cucurbitinum, Xanthidium bifidum) have recently been found at Kamanos sites.

Abstract

The collection of pure cultures of algae and cyanobacteria deposited at the Nature Research Centre is a unique and diverse culture collection in Lithuania. It was initiated on the basis of a few national projects in 2010 as an outcome of ecological and molecular studies on invasive and harmful bloom-forming algae and cyanobacteria. To date, the collection holds more than 500 strains, which belong to ten classes, over 70 genera and 140 species. Strains were isolated from Lithuanian freshwaters and the Curonian Lagoon. The collection serves for various research topics including species interactions, molecular analysis, biotechnology (remediation of wastewaters, cell wall disruption, high- and low-value bioproducts), as well as for teaching purposes.

Abstract

Servienė E., Kemežienė I., Kasperovičienė J., čapukoitienė B., Rančelienė V., Koreivienė J., 2012: Optimization of DNA isolation and PCR parameters for RAPD analysis of Gonyostomum semen (Raphidophyceae) [DNR izoliavimas ir PGR parametrų optimizavimas Gonyostomum semen (Raphidophyceae) dumblių RAPD analizei]. - Bot. Lith., 18(1): 40-45. The genomic DNA purification method for Gonyostomum semen algae was optimized by applying different DNA purification techniques and rational modifications. This method allowed to obtain high quality DNA preparations suitable for the phylogenetic analysis and genetic variability investigation of algae. DNA isolated by this method yielded strong and reliable amplification products showing their applicability for RAPD-PCR using random decamer primers. In the present study, the RAPD protocol was optimized for the evaluation of Gonyostomum biodiversity.

Abstract

EU international project of LIFE programme “Algae Service for LIFE” seeks to promote best practices in ecological service and development of circular economy. The goal of the project is to demonstrate integrated efficient management of nutrients and nuisance algal blooms at the catchment scale by harvesting cyanobacteria scums and macroalgae mats in various types of water bodies (rivers, lakes and estuarine lagoon). Also, it seeks to raise awareness of the national and local authorities, business community and society on the environmental, water quality and health hazard issues. The paper provides the idea of applying ecological measures to control algal blooms. Thus, issues related to the causes and mechanisms of eutrophication in inland freshwaters as well as to consequences such as algal blooms are highlighted. The measures proposed in the project are briefly discussed in the light of European Union directives.

Abstract

‘Algae Service for LIFE’, the project supported by the European Union, seeks to promote best practices in ecological service and the circular economy by implementing innovative complex system of three interlinked elements: i) prototypes for harvesting of cyanobacteria and macroalgae biomass; ii) distant methods for surveying of the blooms and defining hot-spots of algal agglomerations; and iii) restitution of harvesting costs by redesigning of waste algal biomass into valuable products. The current paper describes application of algal biomass part of the project by providing actions in redesigning of harvested waste biomass of cyanobacteria and macroalgae into potential valuable products for sustainable management and recycling of environmental resources. It also highlights the socio-economic aspects of the project and added value of the project for the European Union.