scholarly journals Kimmeridgian–Volgian ostracods of Samarskaya Luka: Paleoecological analysis and reflection of sedimentation conditions in rock magnetism

Author(s):  
Julia N. Savelieva ◽  
◽  
Andrey Yu. Guzhikov ◽  

The analysis of the distribution of the Kimmeridgian–Volgian ostracods in the section near the village Valy made it possible to establish a sequence of eight communities, the change of which reflects changes in the ecological conditions in the basin. Changes in sea level fluctuations, the main physical and chemical parameters of the ostracod habitat – temperature, salinity of water, oxygen content in it, eutrophy and concentration of organic matter in sediment – are reconstructed. Information on the magnetic susceptibility and its increase after heating was obtained. Statistically significant relationships between the petromagnetic characteristics and some conditions of sedimentation were established. The conclusion about the relevance of continuing such studies at objects of different ages and genesis was made.

2020 ◽  
Vol 5 (2) ◽  
pp. 59
Author(s):  
Guntar Marolop S ◽  
Peppy Herawati

Peat soil is a type of soil that is formed from the accumulation of plant debris which undergoes a decomposition process. This is why peat soil contains high organic matter and is acidic. Peat soils will affect the parameters of a surrounding aquatic ecosystem, such as the Rasau peat swamp ecosystem in the village of Rantau Panjang. Peat swamp water parameters are influenced by substances stored in the peat such as having a low pH, high heavy metal content, and having high TSS, TDS, BOD and COD values. The water parameter of peat swamp with mangrove vegetation is better than that of peat swamp that does not have mangrove vegetation. This can be seen if the peat swamp water parameters are laboratory tested. The physical parameters of water, namely temperature, TDS, DHL, color, and turbidity were lower in the Rasau peat swamp with mangrove vegetation compared to the non-vegetated ones. The chemical parameters of the Rasau peat swamp with high density mangrove vegetation such as higher pH, and lower BOD, COD, and iron (Fe) when compared to peat swamps without mangrove vegetation. However, the physical and chemical parameters of vegetated and non-vegetated peat swamps are still above the PPRI No. 82 of 2001.


2018 ◽  
Vol 6 (10) ◽  
pp. 123-130
Author(s):  
Yaroslava Zhukova ◽  
◽  
Pylyp Petrov ◽  
Olena Boloba ◽  
Tetiana Ohrimenko ◽  
...  

2000 ◽  
Vol 31 (4-5) ◽  
pp. 411-422 ◽  
Author(s):  
Gísli Már Gíslason ◽  
Jón S. Ólafsson ◽  
Hákon Adalsteinsson

The characteristics of stream and river ecosystems in arctic and alpine areas are determined mainly by the relative contribution of glacial meltwater, snowmelt, rainfall and groundwater. Each source generates a particular seasonal hydrological signature, affecting physical and chemical properties, and hence biological communities. The relative contribution of each source is sensitive to climate change. The study was concentrated on the glacial River W-Jökulsá and some non-glacial rivers in the central highlands of Iceland. The water in the glacial river was entirely glacial meltwater at the glacier margin, but the glacial contribution was about 20% 40 km downstream. However, its tributaries and non-glacial reference rivers were mainly springfed. The invertebrate fauna was confined to Chironomidae of the genus Diamesa close to the glacier, but other taxa (species and groups of species) occupied the river further downstream, where their diversity was close to that found in the reference rivers.


Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 221
Author(s):  
Rafał Tytus Bray ◽  
Katarzyna Jankowska ◽  
Eliza Kulbat ◽  
Aneta Łuczkiewicz ◽  
Aleksandra Sokołowska

The paper presents the results of research on the use of ultrafiltration, using membranes of 200 and 400 kDa separation, for disinfection of municipal treated wastewater. The research was conducted on a fractional technical scale using real municipal treated wastewater from two large wastewater treatment plants treating most of the wastewater over the one-million polycentric Gdańsk agglomeration (1.2 million inhabitants). UF 200 kDa and UF 400 kDa processes enabled further improvement of the physical and chemical parameters of treated wastewater. Total phosphorus (to below 0.2 mg/L–UF 200 kDa, 0.13 mg/L–UF 400 kDa) and turbid substances (to below 0.2 mg/L, both membranes) were removed in the highest degree. COD was reduced efficiently (to below 25.6 mgO2/L–UF 200 kDa, 26.8 mgO2/L–UF 400 kDa), while total nitrogen was removed to a small extent (to 7.12 mg/L–UF 200 kDa and 5.7 mg/L–UF 400 kDa. Based on the reduction of indicator bacteria; fecal coliforms including E. coli (FC) and fecal enterococci (FE) it was found that the ultrafiltration is an effective method of disinfection. Not much indicator bacterial were observed in the permeate after processes (UF 200 kDa; FC—5 CFU/L; FE—1 CFU/L and UF 400 kDa; FC—70 CFU/L; FE—10 CFU/L. However, microscopic analysis of prokaryotic cells and virus particles showed their presence after the application of both membrane types; TCN 3.0 × 102 cells/mL–UF 200 kDa, 5.0 × 103 cells/mL–UF 400 kDa, VP 1.0 × 105/mL. The presence of potentially pathogenic, highly infectious virus particles means that ultrafiltration cannot be considered a sufficient disinfection method for treated wastewater diverted for reuse or discharged from high load wastewater treatment plants to recreational areas. For full microbiological safety it would be advisable to apply an additional disinfection method (e.g., ozonation).


Environments ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 49
Author(s):  
Markéta Šourková ◽  
Dana Adamcová ◽  
Jan Winkler ◽  
Magdalena Daria Vaverková

Illegal dumps and landfills with disposed of tires are a fact of today, which should not be neglected as they represent a great ecological burden for the environment, affect the surrounding nature and disturb the landscape. This research was focused on testing the phytotoxicity of aqueous leachates from the fractions of tires in two sets of experiments—to simulate laboratory conditions (tire leaching in distilled water) and natural conditions (tire leaching in water from a recipient) using the Phytotoxkit testing kit (kit for the establishment of inhibition/stimulation effect on the root development) and the watercress test of phytotoxicity (biological method for the assessment of leachate phytotoxicity). Plants whose seeds were selected for the test were watercress (Lepidium sativum L.) and white mustard (Sinapis alba L.). The aqueous leachate was tested for 38 weeks. During the experiment, physical and chemical parameters were measured at intervals of 14 days by the testing instrument HACH TEST KIT: electric conductivity (EC), amount of dissolved oxygen (LDO) and pH. Results of root growth inhibition (IR) on the seeds of Lepidium sativum L. and Sinapis alba L. exhibited values ranging from 11.73% to 47.74% in the tested samples. Results of germination index (GI) on the seeds of Lepidium sativum L. exhibited values below 66% in the tested samples, which indicated the leachate phytotoxicity. In spite of the fact that similar studies are tackling the acute toxicity of leachates from tires (particularly to algae, embryos and animals), this research brings complementary information in testing the acute phytotoxicity of tire leachates to higher plants.


2020 ◽  
Vol 10 (2) ◽  
pp. 335-346
Author(s):  
Arnold Landry Fotseu Kouam ◽  
Gideon Aghaindum Ajeagah

Abstract The aim of this study is to determine the effectiveness of disinfectant on the viability of eggs from three nematode species (Ascaris, Trichuris, Ankylostoma). It was conducted in a microcosm from June 2018 to June 2019. The wastewater scan was sampled using 5 L sterile containers, the sample was arranged in four replicas, three tests and one control. The test samples received three disinfectants (Moringa, calcium hypochlorite and Moringa associated with calcium hypochlorite) at varying concentrations. The physical and chemical parameters were measured before and after the application of each disinfectant. The samples were then observed under an optical microscope. The viability of the eggs was determined by incubating the Petri dish samples at 30 °C for 30 days. The analyses show that some physicochemical parameters can significantly influence the efficacy of disinfectant on the eggs. The calcium hypochlorite associated with Moringa at 0.6 g/L showed greater efficacy on reducing viability and inactivation of eggs with 100% efficacy yield rates on Ankylostoma and Trichuris trichiuria and 97% on Ascaris lumbricoides eggs; this efficacy is significantly different from that observed on samples treated with Moringa and simple calcium hypochlorite. Of the three parasites tested, A. lumbricoides showed greater resistance to the disinfectant.


2016 ◽  
Vol 29 (1) ◽  
pp. 23-26
Author(s):  
M Iqbal Hossain ◽  
M Nural Anwar

The aim and objective of the study was to isolate and characterize heavy metal tolerant microorganisms from tannery effluents. Six effluent samples were collected aseptically and their physical and chemical parameters were determined. A total of 40 bacterial colonies were isolated from these effluent samples. Among them, six bacterial isolates were characterized provisionally as Alcaligenes aquamarinus, Bacillus coagulans, Bacillus firmus, Enterobacter cloacae, Pseudomonas alcaligens and Pseudomonas mendocina based on morphological, cultural and biochemical characteristics. The survibality and tolerance to heavy metals (Cr and Cu) of these isolates were examined. All the isolates were found to grow at high concentration of CuSO4 (95ppm/ml) and varying degrees of chromium (K2Cr2O7). The highest tolerance was shown by Alcaligenes aquamarinus. These heavy metal tolerant organisms could be potential agents for bioremediation of heavy metals polluted environment.Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 23-26


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