A preliminary floristic survey of aerophytic epiphytic algae from lowland tropical rainforests of Peninsular Malaysia is presented. The algal communities are either dominated by filamentous cyanophytes (e.g. Scytonema, Stigonema) or green algae of the family Trentepohliaceae. As concomitant species of Trentepohliaceae-dominated communities the coccal and filamentous green algae were frequently observed. In cyanophytes-dominated samples green algae were rarely recovered. In many recorded species the determination up to the species level has not been possible. Some of the isolated strains will be described as new taxa in future. The significant difference in species composition of investigated samples indicates a huge potential of algal biodiversity in aerophytic biotopes of tropical rainforests....
The species composition of phytoplankton in several pools in the Litovelské Pomoraví Protected Landscape Area and the physical and chemical conditions of pools were studied from 1996 to 1997. Approximately 200 taxa of algae and blue-green algae were identified. Euglenophyta was diverse and dominant group; especially Euglena hemichromata, E. spirogyra, Trachelomonas volvocina, Phacus orbicularis a P. pleuronectes occurred in samples regularly. The mass occurrence of Hydrodictyon reticulatum were observed in one of these pools....
The investigation is aimed at re-cultivation in the area of the Krušné Hory (Krušné Mountains) in the Czech Republic. In this area, mainly in the town of Most region, there are many coal mines. The re-cultivation by inundation has been used since 1998. In this paper, the toxicity of the Bílina River profile is evaluated and the possible influence of water and sediment quality on biological revival is assessed. Three types of samples were tested - water from the river profile, black mud with oil products odour and sand from the stream center line. These samples were tested by standard acute toxicity tests on green alga Scenedesmus quadricauda strain Greifswald 15, seeds of Sinapis alba and small crustaceans Daphnia magna strain Straus. The acute toxicity bioassays on Daphnia magna did not exhibit any signs of toxicity and it was recommended to use chronic tests on this organism. Also, no inhibitory effects on the growth of Sinapis alba roots were found. A high growth inhibition of the alga Scenedesmus quadricauda was found. In the culture of Scenedesmus quadricauda teratological formations occured....
The seasonal changes of phytoplankton and selected ecological parameters (temperature, pH, oxygen, conductivity, nutrients) were studied in the years 1998 and 1999 at gravel-pit Chomoutov (Olomouc, the Czech Republic). Long-term changes in the species composition and proportions of the main algal groups during last three decades are discussed. Subsequent eutrophication was found with the come back of water blooms of Aphanizomenon flos-aquae....
In nature, organisms grow in gradients of different conditions. For biochemical, physiological and ultrastuctural studies it is necessary to cultivate the organisms in strictly defined conditions. Cultivations in liquid media or on solid ones allow modelling of gradient of only one condition, usually concentration of a nutrient or a toxic chemical. Cultivation in crossed gradients of temperature and light provides various combinations of different values of temperatures and irradiances. A new unit for crossed gradients is commercially available and its properties are characterised here....
Interlaboratory comparison method for identification of cyanobacteria is proposed. Formalin preserved samples of water blooms or samples collected with plankton net were determined using light microscope. The correct identification of dominant species in each sample was evaluated according to the simple point system. Advantages and disadvantages of this method are summarized....
Two methods (new miniaturized method according to TNV 757741 and standard method were compared. The new method was found comparable with several advantages. The older method can be replaced by the new one without problems or both of them can be used for the same purpose.
Symbiosis represents a widely distributed principle of mutual relationships among organisms, belonging to different systematic groups. The cell endosymbiosis is considered to be the most important event, which starts the evolution of all eukaryotic organisms. We recognize about five successful endosymbioses. Some of them resulted in obtaining mitochondria the peroxisomes, perhaps derived from different groups of bacterial ancestors. The special interest represents the origin of the chloroplasts. As it was suggested using the molecular methods, the single-celled cyanobacteria were the ancestors of chloroplasts in glaucophytes, red and green algae. All these groups are classified into kingdom Plantae. Green algae and vascular plants form a monophyletic group. Their chloroplasts are surrounded only by double membrane envelopes, no connection with endoplasmic reticulum or with the nuclear envelope were observed. Endosymbiosis with cyanobacterial chloroplast ancestor is considered to be the primary endosymbiosis. It was of an ancient origin with the age of about 2 billion years. Chloroplasts of other algal divisions were obtained via secondary, sometimes even as tertiary endosymbioses. In dinophytes and euglenophytes, the plastids are the remainder of single celled eukaryotic algae, covered with the triple envelope membranes. Two inner membranes are similar to the chloroplast envelopes in plant chloroplasts, the third outer membrane is of unknown origin. Some experts consider the third plastid membrane as a phagosome (food vacuole) membrane. No connections with the nuclear envelope were observed. In cryptophytes and chromophyte algae (Chromophyta, syn. Heterocontophyta, syn. Ochrista) and Haptophyta (syn. Prymnesiophyta) plastids are covered with four membranes, two additional membranes are derived from the rough endoplasmic reticulum, which is often connected with the outer membrane of nuclear envelope. This kind of endosymbiosis is called the secondary symbiosis, and is much younger than the primary symbioses. Taking in account the six- kingdoms system of life proposed by CAVALIER-SMITH (1998), the secondary endosymbioses are classified into two different kingdoms: Protozoa (Dinophyta, Euglenophyta) and Chromista. The primary endosymbioses form the kingdom Plantae. The classification of Chlorarachniophyta is not clear and recently they are not mentioned as a separate division. Besides Chlorarachnion reptans, some other filarplasmodium forming protozoans containing plastids (Chrysarachnion, Chrysophyceae, Myxochloris, Xanthophyceae) or without plastids (Corallomyxa, Reticulosphaera, GRELL 1991) were recognized....
