Utilisation of blue-green algae as biofertilisers

Biologically active compounds may be liberated from blue-green algae growing on the surface of moist soils. Such compounds may also be released as exudates from algae grown in liquid culture.This report describes inoculation of soils in pots, containing radish or tomato plants, with algal suspensions or exudates, which resulted in increased growth rates of both plants and increased their overall yield. Autoclaved exudates were generally as effective as fresh exudates. Interaction of effects between the various active substances depends on the algal species and method by which the soils are amended.     

A quantitative study of calcareous stream and Tintenstriche algae from the Malham district,Northern England

The algal floras of two limestone streams and two calcareous Tintenstrichen are described and compared. The most important factor governing the distribution and abundance of species was the availability of water. Permanently wet stands, dominated by filamentous blue-green algae (Schizothrix calcicola and Phormidium incrustatum) had a greater species diversity than stands subject to frequent drying which were dominated by coccoid blue-green algae (Gloeocapsa spp.).

Significant correlations were found between S. calcicola and water pH (+ve), total species numbers and pH (+ve), filamentous blue-green algae and aufwuchs thickness (+ve) and Calothrix numbers and rock mass colonized (+ve).

The algal flora of the Tintenstrichen and the streams differed, although both developed upon the same limestone formation. The results are discussed with reference to previous work, substratum stability, aufwuchs structure, water chemistry, light and temperature.     

RHODOSORUS MARINUS GEITLER: A NEW ADDITION TO THE MARINE ALGAL FLORA OF THE WESTERN HEMISPHERE

Rhodosorus marinus Geitler, previously known only from the Old World, is reported from material collected in the Florida Keys, thus taking its place with Chroothece richteriana Hansgirg in Wittrock and Nordstedt and Porphyridium cruentum (S. F. Gray) Nägeli as the third member of the Porphyridiales known for the marine algal flora of the Americas. Its apparent sensitivity to bright light, tolerance of high salinities, and possible confusion in identification, under certain conditions, with the red pigmented, coccoid, blue-green algae, are noted.     

固氮蓝藻“红圈病”的研究——Ⅰ.“红圈病”在大面积培养蓝藻中的危害以及防范措施

对蓝藻“红圈病”的病症、发病条件、传播程度方式、危害进行了研究。结果表明,发病条件与蓝藻最佳生长条件基本一致;病原通过水体和带病藻体传播,对藻的产量和质量均造成严重危害。同时探讨了综合防治措施。     

Effect of growth and subsequent decomposition of blue-green algae on the transformation of iron and manganese in submerged soils

N₂-fixing blue-green algae (Cyanobacteria), besides enriching soils with N and organic carbon, may modify a number of chemical and electro-chemical properties of the soils resulting in a change in availability of some micronutrient elements. Keeping this in view, an experiment was conducted to study the effects of growth and subsequent decomposition of blue-green algae on changes in the different forms of Fe and Mn in four soils under submerged condition. A mixed algal culture containing Anabaena, Nostoc, Cylindrospermum, and Tolypothrix was used as inoculum. It was allowed to grow for 2 months, after which the soils were sequentially extracted with (i) M NH₄OAc (pH 7.0), (ii) M K₄P₂O₇, (iii) 0.1 M NH₂OH.HCl (pH 2.0), (iv) 0.2 M (NH₄)₂C₂O₄ (pH 3.0) and (v) 0.1 M ascorbic acid to obtain water-soluble plus exchangeable, organically bound, easily reducible, amorphous oxides-and crystalline oxides-bound forms of Fe and Mn, respectively, both during the growth as well as the subsequent in-situ decomposition of the algal biomass in soils. Iron and Mn in the extracts were estimated by atomic absorption spectrophotometry.The results showed that growth of blue-green algae in submerged rice soils caused a decrease in the NH₄OAc-extractable forms of Fe and Mn with concomitant increases in all the other four determined forms of the elements. Such decreases and/or increases in different forms of Fe and Mn in soils were explained as being due to release of O₂, addition of organic matter and liberation of extracellular organic compounds by the blue-green algae during their growth. The decomposition of algal biomass resulted in an increase in the NH₄OAc-, K₄P₂O₇- and (NH₄)₂C₂O₄-extractable forms of Fe and Mn with a simultaneous decrease in the NH₂OH · HCl- and ascorbic acid-extractable forms. Development of strong reducing conditions and formation of organic acids with chelating properties were suggested as being the cause of the above changes. The implication of these changes in the forms of Fe and Mn for the Fe and Mn nutrition of rice plants were discussed.     

Algal studies of the Danish Wadden Sea. V. Blue-green algae in higher salt march areas — their seasonal and spatial distribution

The blue-green algal flora in the higher salt marsh areas (above average high tide level) at Rejsby in the Danish Wadden Sea area has been investigated regularly throughout a one-year period. Twenty nine pigmented and two colourless taxa were recorded, and their morphology described in detail. The blue-green algae were particularly well developed in the the grazed Puccinellia marsh, at other sites the occurrence was scattered. In winter and spring few algae were seen. Mats appeared in June and then persisted for shorter or longer periods, in some areas throughout the rest of the year. On the basis of frequency analyses, thirteen assemblages characterized by the dominating species were recognized. Factors affecting the spatial and temporal distribution are discussed. The assemblages are compared to the algal communities described by Polderman.     

Some algae from the Red Sea Hills in north-eastern Sudan

The algae contained in some plankton samples from several localities on four wadi in N.E. Sudan were examined. The observed algae amount to 260 taxa, of which the diatoms, representing 50% of the algal flora, are the most numerous. Other large groups are the blue-green algae (17%) and the green algae (24%) among which the desmids (6%) are rather unimportant.     

Effect of temperature on chlorophyll stability of some subaerial blue-green algae

Chlorophyll stability index of eight subaerial blue-green algal species, collected from their natural habitats, i.e., bark of trees, soil and roof-tops and from cultures, has been determined. The algae from natural habitats showed greater chlorophyll stability compared to those algae from cultures. Among the natural algae, high chlorophyll stability was observed in the algae inhabiting adverse habitats. A slight modification in the method of Murty and Majumder (1962) for determination of chlorophyll stability index has been made. Here the total percentage loss in the amount of Chl alpha of heated sample in relation to its unheated sample has been considered as chlorophyll stability index.     

兰州五泉山的藻类及其分布

以兰州五泉山为该地藻种资源库,对其中水生、陆生生境中藻类的种类多样性、群落结构、分布特点进行了研究。结果发现该地藻类植物65种(含4变种),包括蓝藻、绿藻、硅藻和红藻,其中硅藻种类最多(29种),其它依次为蓝藻(24种)、绿藻(11种)和红藻(1种)。水体中共42种,硅藻最多,有26种,其次蓝藻8种,绿藻7种,红藻1种,不同水体中优势种和亚优势种不同。土壤生境中发现20种,蓝藻13种,绿藻4种,硅藻3种,且非洲席藻和小球藻分为优势种和亚优势种。7个种类在水、陆两大生境都有分布,而且它们主要是丝状蓝藻。     

Effect of blue-green alga (Cyanobacteria) and their exometabolites on formation of resting forms and variability of Yersinia pseudotuberculosis

Research, carried out with the use of bacteriological methods and polymerase chain reaction, revealed that the transformation of Y. pseudotuberculosis, associated with blue-green algae Anabaena variabilis, into resting (noncultivable) forms took shorter time than in soil extract containing no algae. The exometabolites of "old" cultures of these algae sharply accelerated the formation of resting Y. pseudotuberculosis forms. The influence of the algae and the products of their metabolism was manifested far more intensively at 22 degrees C than at 4 degrees C. After passage through infusoria resting Y. pseudotuberculosis forms, preserved in the mucous covering of cyanobacteria, partially reverted into vegetative forms, capable of growing on solid culture media. The revertants essentially differed from the initial vegetative forms by having lower enzymatic activity, agglutinability and cytopathogenicity, as well as by the loss of plasmid p45. The probable role of blue-green algae, widely spread in soils and water reservoirs, in the processes of reversible transformation of Y. pseudotuberculosis vegetative and resting forms, closely connected with seasonal changes of temperature conditions.     

Preliminary studies on algal succession in raw and stabilized sewage

Summary The composition of algal flora and the periodicity of algae in raw and stabilized sewage have been investigated. 36 genera and 70 species of algae are reported.Members of Cyanophyta and Euglenophyta predominate in raw sewage, and there is little variation in the algal flora in different seasons.There is a marked and rapid change in the algal flora of stabilized sewage as compared to raw sewage. Members of Chlorococcales ultimately become dominant in stabilized sewage.     

Concentration of 137Cs, 65Zn,and 85Sr by fresh-water algae

Differences in the concentration and retention of ¹³⁷Cs by unicellular diatoms, filamentous green algae, and filamentous blue-green algae were demonstrated under both batch and continuous-flow culture conditions. ¹³⁷Cs concentration factors were generally higher by a factor of 2 in batch tests than in continuous flow tests. In retention studies, ¹³⁷Cs was desorbed more rapidly from algae under continuous-flow conditions. Studies with blue-green algae indicate that ¹³⁷Cs concentrations in the various species were more closely related to the surface-to-volume ratios of algal cells than to the systematic relationships of the three species. Continuous-flow studies indicated no differences among three species of filamentous green algae in the concentration of ¹³⁷Cs, ⁶⁵Zn, and ⁸⁵Sr. However, the average concentration factors of the radionuclides were considerably different: 3800 for ⁶⁵Zn, 460 for ¹³⁷Cs, and 230 for ⁸⁵Sr. These radionuclides were rapidly desorbed following the transfer of algae to nonradioactive media. The desorption rate was inversely related to the concentration rate.     

Microplate Technique for Determining Accumulation of Metals by Algae

A microplate technique was developed to determine the conditions under which pure cultures of algae removed heavy metals from aqueous solutions. Variables investigated included algal species and strain, culture age (11 and 44 days), metal (mercury, lead, cadmium, and zinc), pH, effects of different buffer solutions, and time of exposure. Plastic, U-bottomed microtiter plates were used in conjunction with heavy metal radionuclides to determine concentration factors for metal-alga combinations. The technique developed was rapid, statistically reliable, and economical of materials and cells. Results (expressed as concentration factors) were in reasonably good agreement with literature values. All species of algae studied removed mercury from solution. Green algae proved better at accumulating cadmium than did blue-green algae. No alga studied removed zinc, perhaps because cells were maintained in the dark during the labeling period. Chlamydomonas sp. proved superior in ability to remove lead from solution.     

Observations of Toxic Blue-Green Algae (Cyanobacteria) in Some Scandinavian Lakes

Blooms of blue-green algae from 51 eutrophic Scandinavian lakes were investigated during the period 1978–1984, to ascertain the occurrence of toxinogenic species. Toxicity assays were performed by intraperitoneal injection of suspensions of freeze-dried algal material in mice. Toxin-producing blue-green algae were found in 30 lakes. They belonged to 11 different species of the six genera Anabaena, Aphanizomenon, Gomphosphaeria, Microcystis, Nodularia and Oscillatoria. The presence of toxinogenic strains of blue-green algae seemed quite constant in several of the localities studied. In some lakes, more than one toxic species were found to develop simultaneously. The level of toxicity showed large variation (MLD100, 6 to > 2500 mg/kg), but clinical and pathological changes were quite uniform. The results indicate that water-blooms of toxin-producing blue-green algae, in the geographical area in question, are regionally widespread. In some localities, blooms of blue-green algae are apparently always toxic. Several aspects of the toxic blue-green algae problem are discussed.     

Multivariate Interpretation of the Distribution of Nitrogen-fixing Blue--green Algae in Rice Soils in Central Sri Lanka

The ecology of nitrogen fixing blue-green algae in rice fieldsof Central Sri Lanka was studied using multi-variate techniquesof analyses. In this study 73 strains of heterocystous blue—greenalgae, belonging to 21 genera were isolated and the distributionof the 46 most abundant strains was examined in relation toecological parameters. Besides pedological factors such as pH, water holding capacityand available phosphorus; environmental factors including rainfalland altitude have shown up as parameters influencing the distributionof the algal species. On the other hand, soil organic carbon,total nitrogen, potassium and calcium, do not appear to playan important role in determining the composition of the algalflora. While certain algal species were ubiquitous in their distributionsome were restricted, and a few even showed a tolerance to standswith low soil pH and low levels of phosphorus. The agronomicpotential of such species is of value especially in relationto rice-growing soils of this District, where low pH and lowlevels of phosphorus are major limiting factors for the profusegrowth of blue—green algae. Blue-green algae, nitrogen fixation, Sri Lanka, rice-growing soils, multivariate analysis     

Lithophytic algae: A major threat to the karst formation of show caves

Depending on the intensity, quality and duration ofthe illumination, necessary for viewing show caves,conditions conducive for algal growth are created. Although algae are the major component of this flora,ferns and mosses have also been recorded. Little isknown of the algae, except that they are considered anuisance in terms of discoloration and damage to thekarst formations. The occurrence and possible controlof the algal flora has been studied in the CangoCaves, one of the most important touristic sites inSouth Africa. The algal flora is sparse in speciesdiversity and primitive forms are present. They haveparticular physiological adaptations and usingmicro-oxygen liberation and fluorescence measurements,their photosynthetic characteristics were established. Environmentally friendly control measures wereinvestigated and a solution for their control is proposed.     

COMPARATIVE PHYSIOLOGY AND MORPHOLOGY OF SIX STRAINS OF STIGONEMATACEAN BLUE-GREEN ALGAE1

Six strains of branched blue-green algae were examined in a search for lines to an explanation for apparent noncompetitiveness. Classical taxonomic treatments were often inadequate for confident species determination; forms that were very differ their morphologically frequently “keyed” to the same species. Strain distinctions based on comparative morphological and physiological studies were inconclusive. With the exception of 1 species, there were no substantial differences in physiological rates. In addition to the branching habit, diversity of cellular form was found to be an outstanding group characteristic. Individual cells of developing trichomes became a spore-like and then divided to produce either cell clusters or lateral branches. The eventual separation of daughter cells by sheath materials may be analogous to spore formation in Nostocales and could be the factor which determines the nature of these organisms. The Stigonemataceae may not represent the pinnacle of blue-green algal development but may, instead, be a primitive and basic form linking coccoid and filamentous algae.     

Phycobilisomes in Blue-Green Algae

Fifteen species of freshwater blue-green algae, including unicellular, filamentous, and colonial forms, were subjected to a variety of fixatives, fixation conditions, and stains for comparison of the preservation of phycobilisomes. Absorption spectra of the corresponding in vivo and released photosynthetic pigments, in 10 of the species that were maintained in culture, demonstrated the presence of phycocyanin in all 10 species and phycoerythrin in only 2 of them. Spectroscope and electron microscope evidence was obtained for localization of phycobiliproteins in phycobilisomes of Nostoc muscorum. Phycobilisomes were observed in all species examined in situ, strenghening the hypothesis that phycobilisomes are common to all phycobiliprotein-containing photosynthetic blue-green algae.     

Long term study on the influence of eutrophication, restoration and biomanipulation on the structure and development of phytoplankton communities in Feldberger Haussee (Baltic Lake District, Germany)

Feldberger Haussee provides a classic example of eutrophication history of hardwater lakes in the Baltic Lake District (Germany) and of changes in their algal flora during the 20th century. The lake originally was regarded as slightly eutrophic. A process of drastic eutrophication from the 1950s until the end of the 1970s caused mass developments of blue-green and green algae. A restoration program was started in the 1980s to improve the water quality of the lake using both diversion of sewage outside the catchment area, and biomanipulation by altering the fish community. This restoration program led to positive changes in the lake ecosystem. Direct effects of biomanipulation resulted in an increase of herbivorous zooplankton, a decrease of phytoplankton biomass, and an increase of water transparency. The recovery of Feldberger Haussee also may have been indirectly enhanced by an increase in nutrient sedimentation as a consequence of intensified calcite precipitation, decrease in phosphorus remobilization due to a pH-decrease, increased NIP-ratio, and recolonization of the littoral zone by macrophytes. This paper concentrates on the long term development of the phytoplankton community as a response to changes in the food web structure as well as to alterations in the chemical environment of the algae. Both are reflected in four major stages passed by the algal assemblage between 1980 and 1994: (1) From 1980-summer 1985 dense green algal populations were found indicating similar conditions as in the 1970s during the period of maximum eutrophication. (2) A diverse phytoplankton community during summer 1985–1989 showed the first effects of a recovery. (3) From 1990–1992 the phytoplankton was characterized by ungrazeable filamentous blue-green algae first of all as a response to increased herbivory of zooplankton on edible species and to increasing N/P-ratios. (4) Finally, the algal species diversity increased in 1993 and 1994 whereas the phytoplankton biomass decreased showing the success of the combined restoration measures.     

娘子关泉域藻类植物的初步研究

1984～2000年间,对娘子关泉域的藻类植物进行了15次采集,共采得藻类植物标本200余号。经鉴定,有107种,隶属7门,32科,49属。其中,以绿藻门的种类最多,有13科,19属,45种。其次是裸藻门,有2科,7属,26种。排在最后的是轮藻门,有1科,1属,3种。群落主要包括8类,即刚毛藻-红毛菜群落(Cladophora Bangia community),刚毛藻群落(Cladophora community),拖拉藻-轮藻群落(Chara Thorea community),弯枝藻-拖拉藻群落(Composopogon-Thorea community),水绵-双星藻群落(Spirogyra Zygnema community),无隔藻群落(Vaucheria community),串珠藻群落(Batrachospermum community)和泡状饶氏藻群落(Jaoa community)。其中,有的群落类型已趋于消失或消失,许多种类已成为濒危物种,其原因主要是人为因素造成藻类植物生存环境的改变或破坏。本文也提出了相应的保护对策。