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At least 19 recordsLinked to original sources
PubMed1992

Eutrophication, marine biotoxins, human health.

Eutrophication phenomena in marine coastal waters can today be explained on the basis of natural or anthropogenic causes. Undesirable effects and also sanitary problems in both types of eutrophication are often produced, but they may differ greatly in frequency and significance. Some algal biotoxins can affect both marine animals and man, whilst others affect man alone. From data currently available it appears that the sanitary state of man can be affected through the digestive, respiratory and cutaneous apparatus. Four main dinoflagellate biointoxications are now recognized: paralytic shellfish poisoning (PSP), neurotoxic shellfish poisoning (NSP), diarrhoetic shellfish poisoning (DSP), and venerupin poisoning. Other biointoxications are due to a diatom bloom responsible for amnesic shellfish poisoning (ASP) and to blue algae blooms which have effects on the skin and the respiratory tract. All these marine toxins are considered and particular attention is paid to: producing organisms, chemistry of the components, compromised sea foods, methods of analysis, occurrence worldwide, human intoxications, toxicology and mechanism of action on a molecular level, therapeutical notes, tolerance levels and remarks on safety. Attention is also paid to the relationship between the anthropogenic eutrophication and PSP and DSP since these are the most widespread biointoxications from toxic marine dinoflagellates in the world today and for which the European Economic Community (EEC) is proposing health legislation such as tolerance limits and methods for official analysis. In view of the harmful potential of coastal anthropogenic eutrophication, the main current committment of various countries concerns control. Finally, it is important to develop a suitable monitor research system using all the specific standards of allowed toxic substances, and also research on effective antiodotes against all biotoxins.

Animals↗
PubMedDate not supplied

Phosphorus and the eutrophication of lakes--a personal view.

The availability and abundance of biologically-active forms of phosphorus in natural waters are briefly reviewed in relation to the requirements, growth and development of algal populations. The consequences of artificial enrichment of lakes with agricultural, domestic and industrial effluents ('eutrophication') attributed to increased phosphorus loading are compared with evidence from a selection of natural lakes and experimental systems in the UK. The suggestion is made that increased loadings on richer lakes make relatively less impact than does mild eutrophication of unproductive waters. Within limits the effects of eutrophication are reversible.

Chlorophyll↗
PubMed1993

Phosphorus-nitrogen loading and trend of fish catch as index of lake Mariut eutrophication.

Lake Mariut was considered in the past to represent an important source of fish production in Alexandria especially during the periods which were characterized by low catch from its marine fisheries. The growing population in Alexandria and the expanding industries around the lake were accompanied with increased quantities of domestic and industrial wastes discharged annually into the lake proper. These quantities were increased from 192 million cubic meters in 1974 to about 300 million cubic meters in 1992. Consequently, the water quality in this basin was highly deteriorated and changed to become markedly eutrophic. High input of nutrients through sewage and industrial wastes has considerably increased the phosphorus and nitrogen load in the lake proper. Phosphorus and nitrogen loading in this basin were estimated in 1992 to be 60.2 gm/m3 P/y and 79.8 gm/m3 N/y. According to the nutrient concept given by Vollenweider (1974), these two figures have provided an evidence that the lake proper was strongly changed from oligotrophic to polytrophic phase. The trend of its total fish catch as well as the trend of different fish categories catch during the period 1970-1992 also confirms its eutrophication. This is in addition to bad changes that took place with respect to environmental conditions due to the continuous inflow of domestic and industrial wastes from different sources into this part of Mariut lake. Marginal increments of the lake proper total catch were decreased from 20.6% in 1970 to -28.8% in 1992, while the marginal increments of Tilapia sp., Clarias sp, Anguilla sp. and Mugil sp. were decreased from 21.4%, 14.3%, 29.8%, and 28.9% respectively in 1970 to -29.1%, -25.3%, -43.0%, and -36.8% in 1992. Based on these two indices of the lake proper eutrophication, the expected improvement of its environmental conditions will take several years after treating all inland discharges flowing into the lake and/or diverting all relevant outfalls away from this basin.

Animals↗
PubMedDate not supplied

[Fetal movement and heart acceleration behavior in eutrophic and hypotrophic fetuses in the 36th to 40th week of pregnancy].

By means of combined ultrasonic and cardiographic monitoring, the movement and acceleration behaviours of 44 eutrophic fetuses were compared to those of 19 fetuses with body weights between the 6th and 10th weight percentiles according to Kyank and to 21 fetuses with body weight not greater than the 5th weight percentile. The eutrophic fetuses moved more frequently and--related to 10 minutes examination time--over longer total periods than did the fetuses with intrauterine growth retardation. The longest mean duration of isolated fetal movement, however, was observed in the hypotrophic fetuses. With regard to fetal resting and activity stages, the highest percentage (10%) of fetal resting stages was found in the fetuses less than or equal to the 5th weight percentile. 93% of all accelerations in fetal heart rate obviously resulted from fetal movements, duration and amplitude of the accelerations depending on the duration of fetal movements. The degree of heart rate responses to fetal movements was different in the three groups examined. Standard weight fetuses responded most intensively. The percentage of fetal movements resulting in accelerations was highest (76%) in the group of the eutrophic fetuses as well. The mean duration of acceleration was most marked in the group of fetuses less than or equal to the 5th weight percentile (32.8 sec) and so was the mean acceleration amplitude in the normotrophic fetuses (19.7 bpm). Decelerations following accelerations in fetal heart rate did not differ in the three groups examined with regard to their number, amplitude and duration.

Female↗
PubMed1994

Toxic effects of water eutrophication on pancreatic, hepatic and osteogenic tissues of rats.

Pollution, industrial solvents, concentrations of metals and other environmental agents are widely related to biochemicals values which are used in disease diagnosis of environmental toxicity. A rat bioassay validated for the identification of toxic effects of eutrophication revealed increased serum activities of amylase, alanine transaminase (ALT) and alkaline phosphatase (ALP) in rats that received algae, filtered water and nickel or cadmium from drinking water. Serum Cu-Zn superoxide dismutase activity decreased from its basal level of 40.8 +/- 2.3 to 26.4 U/mg protein, at 7 days of algae and at 48 hr of nickel and cadmium water ingestion. The observation that lipoperoxide concentration was not altered in rats treated with filtered water, while amylase, ALT and ALP were increased in these rats and in those treated with nickel or cadmium, indicated that pancreatic, hepatic and osteogenic lesions by eutrophication were not related to superoxide radicals, and might be due to a novel toxic environmental agent found in filtered and non-filtered algae water.

Alanine Transaminase↗
PubMed1971

Nitrogen, phosphorus, and eutrophication in the coastal marine environment.

The distribution of inorganic nitrogen and phosphorus and bioassay experiments both show that nitrogen is the critical limiting factor to algal growth and eutrophication in coastal marine waters. About twice the amount of phosphate as can be used by the algae is normally present. This surplus results from the low nitrogen to phosphorus ratio in terrigenous contributions, including human waste, and from the fact that phosphorus regenerates more quickly than ammonia from decomposing organic matter. Removal of phosphate from detergents is therefore not likely to slow the eutrophication of coastal marine waters, and its replacement with nitrogen-containing nitrilotriacetic acid may worsen the situation.

Acetates↗
PubMed1984

[Electrophysiological studies on the adaptation of eutrophic mature newborn infants during sleep in the first week of life].

The aim of the study was: elaboration of behaviour characteristics of eutrophic healthy newborns during adaptation (first 5 days) by determination of sleep states and interrelation of particular sleep states as well as characteristics of respiratory function in active and quiet sleep. Material comprised 50 eutrophic healthy newborns born at term between 38-41 weeks of conceptional age with body weight 2800-4300 g. 33 newborns were born by spontaneous delivery (SpD) and 17 by primary cesarean section (CS). Normal state of all clinically investigated newborns immediately after delivery and in the newborns period was noted. According to the aim of study polygraphic sleep records were performed in all newborns and they included EEG, chin electromyogram, respiratory and cardiac rates, eye movements and body movements. Recordings time was 2-3 hours. All records were taken during day sleep between 2 feedings (at 9 and 12). From all polygraphic investigations 75 records were selected for detailed analysis. Among them there was 50 records of newborns delivered by SpD and 25 records of newborns delivered by CS. In each consecutive 5 days of life there were analysed 10 records of SpD and 5 of CS. These records were the subject of investigation of behavioural patterns of newborn including sleep and respiratory function in sleep in the first 5 consecutive days of life. Each sleep state (active, quiet and indeterminate) was classified using 4 electropolygraphic parameters (EEG, respiration, eye and body movements). Characteristics of behavioural newborn pattern were determined in consecutive 5 days of life considering the kind of delivery and using quantitative and qualitative analysis of obtained data. Qualitative analysis concerned the occurrence of particular sleep states and the type of the first sleep state beginning the sleep. Quantitative analysis comprised: time duration of wakefulness, time duration of each sleep state--expressed by total time duration of each sleep state and by longest time duration of each sleep state, calculated during 100 minutes of sleep. These values were determined by quantitative analysis of individual records as well as by medium values received from all records in every day of life. Characteristics of respiratory function were analysed analogically in the same 5 days of life with regard to the kind of delivery, independently of active and quiet sleep state.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗
PubMed2025

Agricultural land use and ensuing eutrophication both shape parasitic trematode communities in rural African lakes.

Land use is a major driver of biodiversity loss, but how it impacts parasite communities is scarcely documented. Crater lakes and their catchments in rural western Uganda greatly vary in their intensity of anthropogenic disturbance, thus providing an opportunity to assess the effects of land use on snail-borne parasitic trematodes. We applied state-of-the-art molecular biomonitoring to 2385 Bulinus tropicus snails from 34 lakes to detect and genotype trematode infections. The 45 trematode taxa recovered infect a wide range of final vertebrate hosts, and some can cause health burdens of significant public importance. Using constrained ordinations and generalized additive models, we found that B. tropicus reaches peak abundance in lakes with catchments partly under agriculture, whereas trematode infections increase with B. tropicus abundance and peak at intermediate aquatic productivity. Trematode diversity also increases with aquatic productivity, levelling off only in the most productive lakes. These relationships likely reflect the higher abundance and variety of final hosts sustained by more productive lakes. Finally, we found that land use affects trematode community composition, with more livestock parasites and less bird parasites occurring in agricultural catchments. Our results indicate that both land use and lake eutrophication affect the distribution of hotspots for parasitic disease transmission.

Lakes↗
PubMed1991

The effects of periodic eutrophication on parasitism and stock identification of Trematomus bernacchii (Pisces: Nototheniidae) in McMurdo Sound, Antarctica.

McMurdo Sound, Antarctica, is suited for the study of the effects of eutrophication on diet-related parasites of Trematomus bernacchii (Boulenger, 1902) (Pisces). It has been relatively well studied, the environment is predictable, and there are significant differences in primary productivity over small distances. The differences in parasitism for 5 helminth species can be attributed to the enrichment processes in the sound. The prevalences of the acanthocephalan Echinorhynchus sp., the nematode Ascarophis nototheniae, the digenean Dinosoma sp., and the cestode Phyllobothrium sp. are significantly higher on the east side of the sound than on the west. The prevalence of the digenean Lepidepedon garrardi was significantly higher on the west side. We believe that the differences in the prevalences of infection between the east and west sides suggest that at least the benthic, adult fish do not readily move from one side of the sound to the other. We report the following (new host records are marked by asterisks): Echinorhynchus sp., Corynosoma hamanni (Acanthocephala); Phyllobothrium sp., Diphyllobothrium sp., Trypanorhyncha (Cestoidea); Clavellopsis (Copepoda); Dinosoma sp., Lepidepedon garrardi (Digenea); Pseudobenedenoides brachicola, Polyopisthocotylea (Monogenea); Contracaecum sp., Ascarophis nototheniae (Nematoda); Myxoproteus sp., Henneguya sp., Ceratomyxa sp., and Zschokkella sp. (Protozoa).

Animals↗
PubMedDate not supplied

[Molecular nitrogen fixation in the waters of eutrophic and polyhuic lakes of the Estonian SSR].

A modified acetylene technique was used to assay the rate of molecular nitrogen fixation in Estonian lakes containing methane in the hypolimnion. Methods were elaborated to eliminate ethylene cooxidation by methane oxidizing bacteria. Methane oxidation and nitrogen fixation were found in a narrow microaerobic zone in lakes with the stratification of temperature in the water mass; these biochemical processes occurred when the content of dissolved oxygen varied within the range of 0.1 to 0.8 mg O2 per litre. The rate of these microbiological processes was significantly influenced by trophic relationships with microorganisms from the adjacent ecological niches. In the epilmnion of eutrophic lakes, atmospheric nitrogen was fixed by the blue-green algae Anabaena and Gloeocapsa minima and by the heterotrophic bacterium Azomonas agilis; in the microaerobic zone of metalimnion, atmospheric nitrogen was fixed by the methane oxidizing bacteria Methylosinus trichosporium and M. sporium and by the hydrogen oxidizing bacterium Mycobacterium flavum. In polyhumic lakes, nitrogen fixation was performed by the bactera Az. insignes, Methylosinus trichosporium, M. sporium and Mycobacterium flavum only in water layers near the bottom with microaerobic conditions.

Estonia↗
PubMed1974

Sewage treatment by controlled eutrophication: bacterial study.

Several groups of bacteria were isolated and identified in an evaluation of the microbiological properties of a sewage treatment system involving the process of controlled eutrophication in a marine setting (J. G. Songer, N. M. Trieff, R. F. Smith, and D. Grajcer, 1974). Fecal coliforms, enterococci, Salmonellae, Shigellae, Vibrio parahaemolyticus, and Vibrio alginolyticus were studied at three stages of the treatment process. Significant reductions in fecal coliforms (P < 0.01) and enterococci (P < 0.01) were noted from raw sewage to effluent. Salmonellae and Shigellae were not detected at any stage, nor was V. parahaemolyticus. V. alginolyticus was isolated from the effluent only, reflecting the halophilic nature of the organism; low concentrations in raw sewage increased in the more saline effluent. Brine shrimp (Artemia salina), the herbivores in this system, were tested and found to have extremely low numbers of the organisms under study associated with them. Findings point further toward the use of this system as a combined mariculture-sewage treatment facility.

Analysis of Variance↗
PubMedDate not supplied

[Effects of nitrogen nutritional deficiency on the distribution of particular lipids in a eutrophic lake milieu].

The seasonal distribution of particulate lipids coupled with N-nutrient availability was studied in eutrophic Lake Aydat (Massif Central, France). The concentrations of lipids ranged between 196.9 and 2971.5 micrograms.l-1 (mean +/- s.d. = 1090.1 +/- 705.5 micrograms.l-1. Lipids were abundant in summer and fall when nitrates were insufficient reflecting thus an orientation of cell metabolism towards an accumulation of storage products. In such conditions, the heterocystous Cyanobacteria were found to develop due to their competitive advantage of exploiting atmospheric nitrogen. Their lipid metabolism did not seem to be affected at least partially by NO3- exhaustion.

Cyanobacteria↗
PubMedDate not supplied

[Molecular nitrogen fixation in eutrophic Beloye Ozero].

The rate of production and mineralization of organic matter and the rate of fixation of molecular nitrogen were assayed in th eutrophic lake Beloye (near Moscow) at the end of summer stagnation (1976). The content of hydrogen sulphide reached 6.8 mg per litre which resulted in a change of the ecological environment in the lake. The fixation of molecular nitrogen in water layers was characterized by three maxima: 5.0 mcg N per litre per 4 hours (surface); 4.2 mcg N per litre per 4 hours (metalimnion) and 2.8 mcg N per litre per 4 hours (at bottom). The fixation of nitrogen in the trophogenous layer involved mainly the blue-green alga Anabaena. In the sulphide zone, molecular nitrogen was fixed by butyric and sulphate-reducing bacteria.

Cyanobacteria↗
PubMed1989

[Morphometric studies of histologically classified chorionic villi of human placentas. 1. Placentas of eutrophic and hypotrophic full-term infants].

Occurrence of mature and immature chorionic villi was morphometrically analysed in 30 human placentae of children born on term. The following results were obtained from a method specially developed for surface determination of villus cross-section: The surface of mature villi (end or absorption villi) in children born on term with low birth weight was much smaller than that of immature villi. Total surfaces of mature and immature villi were almost equal in size as of the 25th percentile of child weight. The importance is underlined of a "transitional" class between hypotrophic and eutrophic children born on term, and a pattern of results is suggested.

Chorionic Villi↗
PubMed2025

Depth-dependent multi-kingdom microbial interactions and biogeochemical cycling genes in eutrophic shallow lake sediments.

Microorganisms are pivotal to lake ecosystem biogeochemical cycles, yet existing research often focuses on single microbial kingdoms or surface sediments, neglecting multi-kingdom interactions and depth-resolved dynamics. To address these gaps, we used metagenomic sequencing to characterize microbial communities and their functional associations across overlying water and 0-45 cm sediments in four shallow lakes of the middle Yangtze River basin, China. Despite increasing bacterial and fungal diversity with depth, the 0-9 cm surface sediments exhibited the strongest multi-kingdom network connectivity and the greatest microbial stability. Functional genes exhibited clear depth-dependent patterns: nitrogen cycling genes, including those involved in dissimilatory nitrate reduction to ammonium, were most enriched in the upper 0-9 cm of sediment; methane cycling genes were positively correlated with depth; phosphorus cycling genes and some sulfur cycling genes, such as assimilatory sulphate reduction, declined with depth. Sediment microbial assembly was dominated by deterministic processes, in which the vertical distribution of functional genes was primarily dictated by heavy metals and conventional environmental indicators. These findings highlight depth-specific multi-kingdom microbial interactions and their associations with biogeochemical cycling, advancing lacustrine microbial ecology understanding and providing references for lake conservation under environmental change.

Lakes↗
PubMed1975

Eutrophication.

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Ecology↗