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The investigations of the microflora and some groups of microfauna in the protected ecosystem of Zasavica [Serbia, Yugoslavia]
1998
Ratajac, R. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Rajkovic, D. | Stojkovic, S. | Bobic, M.
The protected natural goods of the swamp Zasavica is situated in the north part of Macva (Serbia, Yugoslavia). It is parallel to the flow of the Sava river, which leads to the fact that it used to be the riverbed of the Sava and also of the Drina river. It is interesting for its variety of the plant and animal species. The investigations have been done during autumn period 1997, when the investigated groups were the most heterogeneous. It included algae, Rotatoria,Cladocera, Copepoda and Hydracarina. Among algae, Bacillariophyta were dominant. Among all the investigated groups Rotatoria were the most heterogenous, with great number of the species that are rarely present. Also, some Cladocera species were rare. The estimation of the water quality is given according to the bioindicator species.
Afficher plus [+] Moins [-]Possibility of using bottom fauna community as an indicator of the condition of the river ecosystems
1998
Simic, V. (Prirodno-matematicki fakultet, Kragujevac (Yugoslavia). Institut za biologiju)
In Yugoslavia, application of macrozoobenthos for the purpose of bioindication has been relatively limited. This communities has been used in conjugation with saprobiological methods, while biotic indexes have been unjustifiable used to a small extent. This paper shows the most significant biotic indexes used in the World and possibility of their application in Yugoslavia, as well as the necessity for their modification and elaboration of new ones specific to Yugoslav conditions.
Afficher plus [+] Moins [-]The function of dominant hydrophytes of the Mostonga [Serbia, Yugoslavia] in water quality bioindication
1998
Stojanovic, S. | Nikolic, Lj. | Lazic, D. (Poljoprivredni fakultet, Novi Sad (Yugoslavia))
The Mostonga, once the tributary of the Danube river, now a water-stream with a conducted regime it represents an important water-streams in West Backa (Serbia, Yugoslavia). The most wide-spread hydrophytes (i.e. plant species with the biggest abundance, covering values and occurrence degree) are: Wolffia arrhiza, Lemna gibba, Lemna minor, Lemna trisulca, Spirodela polyrrhiza, Ceratophyllum demersum, Elodea canadensis, Vallisneria spiralis, Stratiotes aloides, Nuphar lutea, Bolboschoenus maritimus, Typha angustifolia, Typha latifolia and Phragmites communis. Based on the analysis of bioindicating values of mentioned hydrophytes of the Mostonga it can be concluded that the present plant species are significant indicators of eutrophication (considerable organic pollution) as well as the increased contents of nitrogen and nitrogen compounds (nutrients), presence of salt in the soil and weakly aerated and mud base.
Afficher plus [+] Moins [-]Phosphatase activity and microbiological parameters as indicators of the canal waters pollution by the oil industry wastewater [Yugoslavia]
1998
Petrovic, O. | Radnovic, D. | Gajin, S. | Matavulj, M. | Trivunovic, V. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju)
On the basis of the enzymatic (phosphatase) activity and microbiological analysis as well, the influence of the oil refinery "Vital" - Vrbas (Serbia, Yugoslavia) wastewater to the recipient DTD (Danube-Tisza-Danube) canal water from the microbiological point of view was determined. In addition the efficiency of the factory's waste water purification plant was estimated. The obtained results of the complex microbiological-enzymological analyses indicated a good water quality at the point where the refinery's water supplies plant is situated (site 1). Very low water quality was determined downstream (site 4) and upstream (site 2) from the inflow of the refinery's wastewater's inflow. The later results might indicated the influence of an unknown pollutant in the region. However, the obtained O/H index value suggests that the self-purification ability of the canal waters is still preserved.
Afficher plus [+] Moins [-][Investigations of water quality of the water micro-reservoir on the Gvozdacka reka river (catchement of the Ibar river), [Serbia, Yugoslavia], using the algas as the bioindicators]
1998
Obuskovic, Lj. | Obuskovic, M. (Institut za vodoprivredu "Jaroslav Cerni", Beograd (Yugoslavia))
The river Gvozdac (Serbia, Yugoslavia) is a small hill water current. It is situated on the mountain Goc and it belongs to the river basin of the river Ibar. During 1965, water micro-reservoir "Gvozdac" on the river Gvozdac was built for the hydroenergetic purposes, with the capacity of about 30,000 cubic meter and the maximum depth, in the present situation of about 2.5 m. Algological and saprobiological enquires have been performed on the water micro-reservoir, on the very river Gvozdac, on the river Ribnica and on some smaller stagnant waters on the given area, in the period between 1988-1994. The analysis have been shown that under the influence of antropogenic factors changes became apparent in the confluence and structure of algae flora as well as a degradation of water quality. The example of water micro-reservoir on the river Gvozdac indicates the destructive processes which are being developed in water micro-reservoirs and which should be stopped, as the significance of the small stagnant waters are not only in keeping and improvement of qualities of greater aquatorials and water tributaries of the river basins but also in the storing of biodiversity of aquatic assotiations in river basins (as well as in algae flora as one of the components).
Afficher plus [+] Moins [-]Biological component in the estimation of the water quality at the Barje [water] reservoir [Serbia, Yugoslavia]
1998
Miljanovic, B. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju) | Pujin, V. | Djukic, N. | Maletin, S. | Ivanc, A.
The investigations of dynamics and composition of plankton, bottom fauna and fish community have been done at three localities (1-inflow, 2-the middle, 3-dam) at the Barje water reservoir (Serbia, Yugoslavia) during 1997. During winter period diatomea Asterionella formosa was dominant at all the localities. At the same time among zooplankton species Rotatoria group was dominant, with the emphasis of Polyalthra dolicoptera at the locality 2, while Keratella cochlearis was dominant at the localities 1 and 3. The present species are oligo- and betamezosaprobionts. Among the investigated bottom fauna species Oligochaeta and Chironomidae were present. The number of oligochaeta was between 1665-7878 ind./square m. By qualitative analyses the domination of Tubificidae family was present. It is known that the presence of this group of organisms and it's high number indicate the organic pollution of ecosystem. 30 individuals of the bighead, (Hypophthalmichthys nobilis) with the average weight of 5.6 kg was captured by net.
Afficher plus [+] Moins [-]Biotransformation and oxidative stress responses in fish (Astyanax aeneus) inhabiting a Caribbean estuary contaminated with pesticide residues from agricultural runoff Texte intégral
2023
Mena, Freylan | Vargas, Seiling | Guevara-Mora, Meyer | Vargas-Hernández , José Mauro | Ruepert, Clemens
The estuarine ecosystem of Madre de Dios Lagoon (MDL), in the Caribbean Coast of Costa Rica, is exposed to contamination with pesticide residues coming from the upstream agricultural areas. Biomarkers can provide a better indication of the fitness of biota in real mixture exposure scenarios than traditional lethal dose toxicity measurements. Here, we measured biomarkers of biotransformation, oxidative stress, and neurotoxicity on Astyanax aeneus, an abundant fish species in MDL. Glutathione S-transferase activity (GST), catalase activity (CAT), lipid peroxidation (LPO), and cholinesterase activity (ChE) were measured in fish collected during seven sampling campaigns, carried out between 2016 and 2018. Pesticide residues were analyzed in surface water samples collected every time fish were sampled. Residues of 25 pesticides, including fungicides, insecticides, and herbicides, were detected. The biomarkers measured in A. aeneus varied along the sampling moments, with biotransformation and oxidative stress signals showing a coupled response throughout the assessment. Furthermore, significant correlations were established between three biomarkers (GST, LPO, and CAT) and individual pesticides, as well as between GST and LPO with groups of pesticides with shared biocide action. Among pesticides, insecticide residues had a major influence on the responses observed in fish. This work demonstrates the chronic exposure to pesticide residues in MDL and how such exposure is related to physiological responses in fish that can affect their health and potentially, the trophic networks. This early warning information should be considered to improve the protection of estuarine ecosystems in the tropics. | El ecosistema estuarino de la Laguna Madre de Dios (MDL), en la Costa Caribe de Costa Rica, está expuesto a la contaminación con residuos de pesticidas procedentes de las zonas agrícolas situadas aguas arriba. Los biomarcadores pueden proporcionar una mejor indicación de la aptitud de la biota en escenarios reales de exposición a mezclas que las mediciones tradicionales de toxicidad de dosis letales. Aquí medimos biomarcadores de biotransformación, estrés oxidativo y neurotoxicidad en Astyanax aeneus, una especie de pez abundante en MDL. Actividad glutatión S-transferasa (GST), actividad catalasa (CAT), peroxidación lipídica (LPO) y actividad colinesterasa (ChE) se midieron en peces recolectados durante siete campañas de muestreo, realizadas entre 2016 y 2018. Residuos de pesticidas se analizaron en muestras de agua superficial recolectadas cada vez que se tomaron muestras de peces. Residuos de 25 pesticidas, incluidos fungicidas, Se detectaron insecticidas y herbicidas. Los biomarcadores medidos en A. aeneus variaron a lo largo de los momentos de muestreo, con señales de biotransformación y estrés oxidativo que muestran una respuesta acoplada a lo largo de la evaluación. Además, Se establecieron correlaciones significativas entre tres biomarcadores (GST, LPO y CAT) y pesticidas individuales, así como como entre GST y LPO con grupos de plaguicidas con acción biocida compartida. Entre los plaguicidas, los residuos de insecticidas habían una influencia importante en las respuestas observadas en los peces. Este trabajo demuestra la exposición crónica a residuos de pesticidas en MDL y cómo dicha exposición se relaciona con respuestas fisiológicas en los peces que pueden afectar su salud y, potencialmente, la redes tróficas. Esta información de alerta temprana debe considerarse para mejorar la protección de los ecosistemas estuarinos. en los trópicos. | Universidad Nacional, Costa Rica | Springer, Alemania | Escuela de Ciencias Biológicas
Afficher plus [+] Moins [-]Journey to the deep: plastic pollution in the hadal of deep-sea trenches. Texte intégral
2023
Abel, Serena M | Wu, Fangzhu | Primpke, Sebastian | Gerdts, Gunnar | Brandt, Angelika
The global increase of plastic production, linked with an overall plastic misuse and waste mismanagement, leads to an inevitable increase of plastic debris that ends up in our oceans. One of the major sinks of this pollution is the deep-sea floor, which is hypothesized to accumulate in its deepest points, the hadal trenches. Little is known about the magnitude of pollution in these trenches, given the remoteness of these environments, numerous factors influencing the input and sinking behavior of plastic debris from shallower environments. This study represents to the best of our knowledge the largest survey of (macro)plastic debris sampled at hadal depths, down to 9600 m. Industrial packaging and material assignable to fishing activities were the most common debris items in the Kuril Kamchatka trench, most likely deriving from long-distance transport by the Kuroshio extension current (KE) or from regional marine traffic and fishing activities. The chemical analysis by (Attenuated Total Reflection Fourier transform infrared (ATR-FTIR) spectroscopy revealed that the main polymers detected were polyethylene (PE), polypropylene (PP) and nylon. Plastic waste is reaching the depths of the trench, although some of the items were only partially broken down. This finding suggests that complete breakdown into secondary microplastics (MP) may not always occur at the sea surface or though the water column. Due to increased brittleness, plastic debris may break apart upon reaching the hadal trench floor where plastic degrading factors were thought to be, coming off. The KKT's remote location and high sedimentation rates make it a potential site for high levels of plastic pollution, potentially making it one of the world's most heavily contaminated marine areas and an oceanic plastic deposition zone.
Afficher plus [+] Moins [-]Agrobacterium tumefaciens C58 presence affects Bacillus velezensis 32a ecological fitness in the tomato rhizosphere Texte intégral
2020
Abdallah, D. B. | Krier, F. | Jacques, Philippe | Tounsi, S. | Frikha-Gargouri, O.
peer reviewed | The persistence of pathogenic Agrobacterium strains as soil-associated saprophytes may cause an inconsistency in the efficacy of the biocontrol inoculants under field condition. The study of the interaction occurring in the rhizosphere between the beneficial and the pathogenic microbes is thus interesting for the development of effective biopesticides for the management of crown gall disease. However, very little is still known about the influence of these complex interactions on the biocontrol determinants of beneficial bacteria, especially Bacillus strains. This study aimed to evaluate the effect of the soil borne pathogen Agrobacterium tumefaciens C58 on root colonization and lipopeptide production by Bacillus velezensis strain 32a during interaction with tomato plants. Results show that the presence of A. tumefaciens C58 positively impacted the root colonization level of the Bacillus strain. However, negative impact on surfactin production was observed in Agrobacterium-treated seedling, compared with control. Further investigation suggests that these modulations are due to a modified tomato root exudate composition during the tripartite interaction. Thus, this work contributes to enhance the knowledge on the impact of interspecies interaction on the ecological fitness of Bacillus cells living in the rhizosphere. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Afficher plus [+] Moins [-]Environmental sustainability assessment of seawater reverse osmosis brine valorization by means of electrodialysis with bipolar membranes Texte intégral
2020
Herrero González, Marta | Admon, Noy | Domínguez Ramos, Antonio | Ibáñez Mendizábal, Raquel | Wolfson, Adi | Irabien Gulías, Ángel | Universidad de Cantabria
The integration of electrodialysis with bipolar membranes (EDBM) with seawater reverse osmosis (SWRO) process influences the two main environmental burdens of SWRO desalination process: climate change, accounted here as carbon footprint (CF) and associated to the high-energy consumption, and the environmental alteration of the vicinities of the facility, due to brine disposal. EDBM powered by photovoltaic (PV) solar energy is able to meet the above-mentioned challenges that arise in SWRO desalination. In addition, HCl and NaOH, both employed in the desalination industry, can be produced from the brines. Hence, environmental benefits regarding the potential self-supply can be achieved. The environmental sustainability assessment by means of life cycle assessment (LCA) of a SWRO and EDBM has been carried out considering four different scenarios. The percentage of treated brines and the influence of the grid mix used for electric power supply has been taken into account. The three different electric power supplies were 100.0% renewable energy (PV solar energy), 36.0% renewable energy (average Spanish grid mix), and 1.9% (average Israeli grid mix). The results showed that the CF per unit of volume produced freshwater for SWRO and the self-supply reagent production scenario for the three Spanish grid mix, the Israeli grid mix, and the PV solar energy were 6.96 kg CO2-eq·m-3, 12.57 kg CO2-eq·m-3, and 2.17 kg CO2-eq·m-3, respectively. | Financial support from MICINN under project CTM2014-57833-R is gratefully acknowledged. Marta Herrero-Gonzalez thanks the MICINN for FPI grant BES-2015-07350. Marta Herrero and Noy Admon thank the Erasmus+ program for the Student Mobility KA107 grant.
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