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EN
Freshwater green algal biofouling of boats refers to the accrual of freshwater green algae on boats immersed in water. The current research focused on the morphological characteristics of the isolates, species ecology, and the physicochemical properties of the water at the sampling sites. Two localities, Haji Zai and Sardaryab, were sampled at the Kabul River in the district of Charsadda, Pakistan. Freshwater green algae causing biofouling were isolated from the boats. A total of three genera: Cladophora, Rhizoclonium, and Spirogyra with fifteen species belonging to the families Cladophoraceae and Zygnemataceae were observed. Statistical analysis reveals significant stimulation of green algal species in the boats’ fouled communities by increases in water temperature, conductivity, and Total Suspended Solids (TSS). The algal growth at the Haji Zai site is suppressed by TDS in autumn (Pearson −0.56) and is stimulated by water temperature in spring (Pearson 0.44). At the Sardaryab site, algae were stimulated in spring by pH of water (Pearson 0.61), and suppressed by Total Dissolved Solids (TDS) in autumn (Pearson −0.43). Statistical analysis indicates that pH, conductivity, and temperature are the main factors determining the algal biofouling in the Kabul River.
PL
Następstwem rozwoju cywilizacyjnego jest pojawienie się związków toksycznych w środowisku naturalnym człowieka. Obecność coraz większej ilości substancji szkodliwych w naszym otoczeniu początkowo wynikała z niezamierzonego uwalniania ubocznych produktów bądź odpadów procesów technologicznych. Kolejne pojawiające się w środowisku toksyny były efektem walki ze szkodnikami, a część z nich, wykazująca najwyższą toksyczność, została użyta w celach militarnych. Badania przeprowadzone w niniejszej pracy miały na celu ocenę wpływu wybranych fosforoorganicznych bojowych środków trujących na wzrost jednokomórkowych glonów Chlorella vulgaris i Desmodesmus armatus. Najniższą toksyczność w stosunku do glonów wykazywał VX, dla którego wartość IC50-72h wynosiła 41,2 mg/l dla Desmodesmus armatus oraz 39,6 mg/l dla Chlorella vulgaris. Wartość IC50-72h w przypadku somanu była dwukrotnie niższa i wynosiła 19,5 mg/l dla Desmodesmus armatus i 7,9 mg/l dla Chlorella vulgaris. Największą toksyczność w stosunku do glonów wykazywał sarin (IC50-72h 10,6 mg/l oraz 13,6 mg/l odpowiednio dla Desmodesmus armatus i Chlorella vulgaris). Wartości NOEC-72h w przypadku VX wynosiły 3,2 i 6,3 mg/l odpowiednio dla Desmodesmus armatus i Chlorella vulgaris. W przypadku sarinu i somanu wartości NOEC-72h były niższe niż 3,2 mg/l dla obu gatunków glonów.
EN
The consequence of civilization development is the emergence of toxic compounds in the environment. The presence of an increasing number of harmful substances in our environment, initially stemmed from the accidental release of waste by-products or processes. Another emerging toxins in the environment were the result of pesticides, and some of them, showing the highest toxicity, was used for military purposes. The aim of this paper is to evaluate the effect of selected organophosphorus warfare agents on the growth of unicellular algae Chlorella vulgaris and Desmodesmus armatus. The lowest toxicity to algae showed VX, for which the IC50-72h was 41.2 mg/L for Desmodesmus armatus and 39.6 mg/L for Chlorella vulgaris. The IC50-72h in the case of soman was twice lower at 19.5 mg/L for Desmodesmus armatus and 7.9 mg/L for Chlorella vulgaris. The highest toxicity to algae had sarin (IC50-72h 10.6 mg/L and 13.6 mg/L respectively for Desmodesmus armatus and Chlorella vulgaris). 72h-NOEC values in the case of VX were 3.2 mg/L, 6.3 mg/L, respectively Desmodesmus armatus and Chlorella vulgaris. In the case of sarin and soman-72h NOEC values were lower than 3.2 mg/L for both species of algae. Our results indicate a diverse toxicity of organophosphorus warfare agents on green algae. Sarin as an unstable substance in soil (half-life < 24 h) proved to be the most toxic in aquatic environment. The compound VX which is potentially the greatest threat (even 170 times lower lethal dose in case of poisoning transdermal) of all test substances showed the lowest phytotoxicity in the growth test. Green algae of the genus Chlorella organisms seem to be more vulnerable to the harmful effects of organophosphorus compounds than type Desmodesmus.
PL
W pracy scharakteryzowano zanieczyszczenia wód śródlądowych pochodzące ze źródeł antropogenicznych i zagrożenia jakie stwarzają dla ekosystemów wodnych. Jednymi z zagrożeń są coraz częstsze zakwity sinicowe. Opisane w pracy działania walki z zakwitami sinicowymi na Jeziorze Dużym w Turawie polegają na zastosowaniu preparatu o nazwie ARMEX 5 zawierający ditlenek chloru jako substancję czynną. Wykazano, że ditlenek chloru w stężeniu powyżej 5 ppm powoduje spowolnienie niepożądanego wzrostu biomasy w badanych próbach wody oraz rozbicie struktur sinic i zmniejsza ich liczebność.
EN
The problem of excessive growth of green algae (Cyanophyta) in Turawa Lake was studied. It was found, that application of chlorine dioxide can effectively restrain undesired development of the algae biomass at ClO2 concentrations over 5 ppm. It was further shown that the applied effective concentration of the studied disinfectant was not harmful for the other higher-organized water organisms.
EN
In this paper, the results of research on phytoplankton species composition along the 145 km section of the Lower Vistula are presented. The research was carried out during the growing season in 1998. All sites were located in the mainstream, both in the river and in the dam reservoir, which is situated in the middle part of the studied river section. As regards the number of species, diatoms and green algae were the most numerous. Most of the species were identified at the site located above the dam reservoir. The fewest number of species were identified at the sites below the reservoir. Damming the river, and therefore changing the water flow velocity, had a clear effect on the species composition and diversity of plankton algae.
EN
The Sulejów Reservoir is a lowland dam reservoir that was constructed in 1973 on the Pilica River at the village of Smardzewice. It is 15.5 km long and has an elongated, trough-like shape. It is characterized by a low depth (mean - 4.5 m), and its mean annual retention time ranges from a dozen to four dozen days. The reservoir is strongly eutrophic due to large loads of phosphorus and nitrogen entering its catchment area. Since the creation of the reservoir, strong water blooms have been caused by Aphanizomenon flos-aquae, Anabaena flos-aquae, Microcystis aeruginosa, and Microcystis wessenbergii. These blooms were associated with the intensified development of green algae, mainly of the genera Coelastrum, Dictyosphaerium, Pandorina, Pediatrum, and Scenedesmus. Beside the blue-green and green algae, the diatoms were the richest in species, of which Asterionella formosa, Aulacoseira granulata, Cyclotella meneghiniana, Diatoma tenuis, Fragilaria capucina, F. Pinnata, F. Ulna, Melosira varians, and Stephanodiscus hantzschii constantly dominated. These three groups were accompanied by Dinobryon sertularia, Ceratium hirundinella, and Peridinium inconspicuum.
EN
The paper presents results of studies on the influence of fresh and aged for 6-12 months aqueous solutions of nitrilotriacetic acid (NTA) on the growth of phytoplankton cells. Axenic strain of unicellular algae Scenedesmus microspina (B2-76) and cyanobacteria Chroococcus minor (A-101) (Gleocapsa minor) were used in the experiments as test organisms. These or-ganisms are common in waters of the Gulf of Gdansk and are important components in the food chain. Concentration of chlorophyll a in test cultures served as a measure of the growth of phytoplankton cell studied. NTA, when added to the culture of Scenedesmus or Chroococcus in the concentration range from 1 to 50 mmol/dm3 exerted a strong growth promoting effect on the cells. NTA solutions aged for 9-12 months stimulated the growth of cyano-bacteria Chroococcus minor to a much larger extent than green algae Scenedesmus microspina. These results indicate that the biological activity of NTA, after long-term incubation as an aqueous solution, undergoes a considerable modification. The effects biological of the end products of such a modification depend on the time of adding of NTA, its initial, concentration as well as on the sensitivity of phytoplankton strains. It is concluded therefore that, the presence of NTA in estuarine and coastal waters may significantly affect the metabolism and growth of phytoplanktonic cells, especially cyanobacteria.
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