Growth Of Freshwater Algae Research Articles

Growth of Freshwater Algae under the Influence of Dissolved Organic Matter

Growth of Freshwater Algae under the Influence of Dissolved Organic Matter

A Discussion on the Influence Mechanism of Iron to Algal Blooms in Natural Raw Water

Through designing orthogonal tests, the influence mechanism of iron to the growth of fresh water algae was studied. The results indicated that the initial Fe concentration of 0.3mg/L or above can lead to high algae relative growth rate while the initial Fe concentration under 0.3mg/L can only generate low algae relative growth rate. The consumption of iron in Group LNLP under low initial Fe concentration and Group HNHP under high initial Fe concentration was in synchronism with the consumption of nitrogen and phosphorus. However, in Group HNHP under low initial Fe concentration and Group LNLP under high initial Fe concentration the concentration of iron decreased with the increase of algal biomass before reaching the peak value of algal biomass and it increased after reaching the peak value in contrary. Among all those 25 groups the order of the peak value of algal biomass from big to small is as follows:All-rich Group>Nitrogen-lacked Group>Phosphorus-lacked Group>Iron-lacked Group>All-lacked Group. The lack of Fe content will restrain the growth of algae. In certain concentration rage algal biomass increased with the increasing of Fe content while Fe content will restrain the growth of algae in contrary if beyond the concentration rage.

The effects of barley straw ( Hordeum vulgare) on the growth of freshwater algae

Bioassays were conducted to determine the efficacy of barley straw liquor in controlling algal growth of 12 freshwater species of algae representing three divisions. Barley straw liquor inhibited the growth of three nuisance algae common in freshwater: Synura petersenii, Dinobyron sp., and Microcystis aeruginosa. However, Selenastrum capricornutum, Spirogyra sp., Oscillatoria lutea var. contorta, and Navicula sp. had significantly increased growth in the presence of straw liquor. The growth of the remainder, Ulothrix fimbriata, Scenedesmus quadricauda, Chlorella vulgaris, Anabaena flos-aquae, and Synedra sp. showed no significant difference from controls. In a related field study, we treated four of six ponds with barley straw and monitored their chlorophyll a levels for one growing season. While phytoplankton populations in all ponds decreased in midsummer, the phytoplankton biomass in treated ponds did not differ significantly from that of control ponds, suggesting that the application of barley straw had no effect on algal growth in these systems.

Biosynthesis and release of methylarsenic compounds during the growth of freshwater algae

Arsenic transformations by freshwater algae have been studied under laboratory conditions. By the use of a new analytical method, we identified methylarsenic(III) species in the growth medium of green-alga Closterium aciculare incubated under axenic conditions. The arsenate concentration in the experimental medium began to decrease just after inoculation, and the levels of arsenite and methylarsenicals increased with the growth of C. aciculare. Initially, most of the arsenate was converted into arsenite, which peaked in concentration during the exponential phase. Methylarsenicals accumulated rapidly in the stationary phase. DMAA(V) production was enhanced when the ratio of phosphate to arsenate decreased in the culture medium. The levels of DMAA(V) increased continuously toward the end of the experiment. On the other hand, methylarsenic(III) species remained relatively steady during the stationary phase. Methylarsenic(III) species accounted for 0–35% of methylarsenicals. These results suggest that arsenite and methylarsenicals (containing methylarsenic(III) species) are supplied by phytoplankton, and serve as evidence of the origin of methylarsenic(III) species in natural waters.

Effect of organic solvents on growth of freshwater algae

The impact of acetone, methanol, ethanol and dimethyl sulfoxide (DMSO) as carrier solvents on two species of algae was investigated. Scenedesmus quadricauda of green algae and Anabaena flos‐aquae of blue green algae were subjected to different concentrations of the studied solvents which ranged from 0.01 to 7.29 mL/L for 10 days in batch studies. The data recommended the use of acetone, ethanol and methanol than dimethyl sulfoxide in this order as a carrier solvent for chemical toxicity tests using a maximum concentration of 7.29 mL/L which represents 0.729% (volume/volume) in the algal bioassay test.

Variations of photosynthetic activity and growth of freshwater algae according to ozone contact time in ozone treatment

The activity of freshwater algae in drinking water supply at various ozone contact times was investigated to evaluate ozonation processes used for sterilization of algae. O production rates of algae just after ozonation were severely retarded even by short ozone contact. The algal growth rate was also declined with increase of ozone contact time and completely inhibited by ozonation for 60 min. These results implied that the usual treatment time applied in conventional ozonation processes is not sufficient but at least 60 min of ozonation is required for a complete sterilization of freshwater algae in drinking water source.

Effect of Certain Herbicides on the Growth of Freshwater Algae

An algal toxicity bioassay using a continuous culture was investigated with respect to the herbicide gardoprim (triazine) and patoran (phenylurea) in order to evaluate the effect of increasing dosages of applied herbicides upon growth, residual herbicide and herbicide accumulation in Nile water algae. Growth patterns exhibited by algae under continuous culture conditions reflect the ability of the algae to overcome inhibitory effects of the herbicides. Nile water algae showed variable ability to accumulate different herbicide. As the herbicide concentratrion increased, the accumulation increased especially for paron. Nile water algae accumulated patron and gardoprim to concentrations of 0.75 and 0.3 mg g-1, respectively. Considerable change occurred in the algal diversity and redundancy after each increase in herbicide concentration. Diversity and redundancy of genera and their recovery varied according to the type of herbicide, its concentration and contact time.

水圏生態系における生産者としての藻類の増殖に及ぼす埋立地浸出水の影響

水圏生態系における生産者としての藻類の増殖に及ぼす埋立地浸出水の影響

The application of batch bioassay techniques to the study of salinity toxicity to freshwater phytoplankton

The effect of salinity additions on the growth of freshwater algae was studied in the laboratory utilizing batch bioassays. These batch bioassays were used to screen variations of ten salts in single addition and the concentration effects of the salts on the productivity of standard test alga and an indigenous diatom from Lake Powell. The indigenous algal genus was found to be more tolerant to salinity addition than the standard test alga. The batch bottle bioassays were conducted following the standard algal assay procedure as closely as possible. Variations in the standard algal assay procedure included media variation with the use of the indigenous alga for test inoculum in the bioassay procedure.

Influence of Polychlorinated Biphenyls (PCBs) on Growth of Freshwater Algae

The toxicity of PCBs (Aroclor 1242) to freshwater algae was analyzed. In two closely related species of Chlorella, one was found to be extremely resistant and the other sensitive. Chlamydomonas reinhardi strains showed temporary sensitivity, which was overcome after 3 days of culture. Results from abiotic preculture indicated that in all cases enzymatic degradation or adsorption of PCBs by cells were not mechanisms explaining the observed differential sensitivities. However, adsorption of PCBs to glass surfaces, coupled with apparent differential uptake properties of the algal species studied, was shown to be the cause of the differential growth effects of PCBs on freshwater algae.

The effect of two organophosphate insecticides on the growth of freshwater algae

Seven freshwater algae were grown in the presence of Abate® 4-E (O,O,O′,O′-tetramethyl-O,O′-thiodi-p-phenylene phosphorothioate) and Dursban® M-3633 (O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl) phosphorothioate) at 1,10, and 100 μg/ℓ active ingredient. The response of different algal groups to the insecticides was highly variable.The growth rate of the nitrogen-fixing blue-green alga Anabaena flos-aquae was increased from 22% at 10 μg/ℓ Abate to 58% at 100 μg/ℓ Abate when grown on nitrogen-free medium. Dursban caused similar growth stimulation. The green alga Chlamydomonas reinhardii showed growth stimulation in response to 100 μg/ℓ Dursban.Significant decreases in growth rate were observed for the green alga Chlorella pyrenoidosa after treatment with 10 μg/ℓ Abate (8%) and 100 μg/ℓ Dursban (12%). The diatom Navicula pelliculosa gave decreases in growth rate of the same order with 10 μg/ℓ Abate or Dursban.No significant effect on the growth rates of the diatom Navicula minima or the blue-green algae Coccochloris peniocystis, Oscillatoria sp., and Anabaena flos-aquae grown in the presence of nitrate was detected after treatment with either insecticide.

Preliminary studies of the effects of S-triazine, carbamate, urea, and karbutilate herbicides on growth of fresh water algae

Preliminary studies of the effects of S-triazine, carbamate, urea, and karbutilate herbicides on growth of fresh water algae

The Current Effect and Growth of Fresh-Water Algae

Phycologists have long recognized that there are algae which grow only in torrents, or at least grow best in rapidly running water. Among these are Lemanea, Hildenbrandtia, Audouinella, Batrachospermum spp., Hydrurus, and Cladophora spp. Microscopic types are represented by Gongosira, Lithoderma, Chamaesiphon, and several species of diatoms. (Butcher 1932, 1940, Fritsch 1935, Chapman 1941, Smith 1950, Tiffany 1951). In southern streams several other species such as Oedogonium kurzii, Vaucheria ornithocephala, and Compsopogon coeruleus are found only in rapids (Whitford 1956, Schumacher and Whitford 1959). For many years it was believed these rapids species grow in streams because lower water temperatures and better aerated water occur there. Evidence lacking to bear out these assumptions. There evidence, however, that some rapids species have a higher respiratory rate than corresponding lenitic species. Limnologists especially have come to recognize an inherent current demand for some species but offer no explanation (Welch 1952). As long ago as 1926 Ruttner partially explained the phenomenon. He pointed out that in quiet water a film deficient in vital materials forms at the surface of a plant or animal, and that in swift water this film swept away thereby bringing more vital materials close to the absorbing surfaces. Moving water, he said, is not absolutely, but rather physiologically, richer in oxygen and nutrients. This physiological richness can be explained on the basis of the laws of cohesion and diffusion. In quiet water a material diffusing inward lowest in concentration at the cell surface, and the concentration increases outward until full concentration reached at some distance away from the cell (Fig. 1). This distance one of the factors determining the gradient. In swift water some of the water low in concentration of the diffusing material swept away bringing water of full concentration closer to the cell surface, thus shortening the distance and steepening the gradient. This increases speed of exchange between the cell and the surrounding water. For the smaller inorganic molecules the gradient extends outward about f4 mm. Evidence for this as well as for the existence of a diffusion shell given in papers by Ferrell, Beatty, and Richardson (1955). They measured fluid-velocity profiles in small glass tubes using various colored and radio-active dissolved materials. In every case the profiles deviated from the expected theoretical figure near the tube wall. The deviation varied also with the size molecule of solute and the density of the solvent. Their conclusion, which seems entirely valid, that outward from the quiet water near the wall produced these deviations. The deviation occurred within }/oo inch (0.26 mm.) of the wall (Figs. 2, 3). Furthermore, the deviation could not be