scholarly journals Assessment of Water Buffer Capacity of Two Morphometrically Different, Degraded, Urban Lakes

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1512
Author(s):  
Jolanta Grochowska

The research was conducted in Karczemne Lake (area, 40.4 ha; maximum (max.) depth, 3.2 m) and Klasztorne Małe Lake (area, 13.7 ha; max. depth, 20.0 m) located in the Kashubian Lake District (Northern Poland). From the beginning of the 1950s, these reservoirs have received municipal and storm wastewater. The long-term process of lake contamination has shaped the specific buffer capacity conditions and influenced the circulation of carbonate and bicarbonate in the water of these ecosystems. Extremely high concentrations of nutrients (Karczemne Lake: max. total phosphorous (TP) level, 7.5 mg P L−1; max. total nitrogen (TN) level, 5.6 mg N L−1; Klasztorne Małe Lake: max. TP level, 20.6 mg P L−1; max. TN level, 43.3 mg N L−1) have caused very intensive primary production processes (Karczemne Lake: max. chlorophyll-a level, 193.40 µg m−3; max. Secchi disc visibility, 0.85 m; Klasztorne Małe Lake: max. chlorophyll-a level, 160.01 µg m−3; max. Secchi disc visibility, 1.15 m). In the polymictic Karczemne Lake, the pH value of all water columns exceeded 10.0 (max. pH, 10.41), and in the meromictic Klasztorne Małe Lake, the pH of the surface water layers oscillated around 9.5. In the polymictic Karczemne Lake, despite intensive photosynthesis, the calcium content and alkalinity were similar throughout the whole water column due to constant circulation. In the meromictic Klasztorne Małe Lake, during the growing season, a decrease in calcium concentration and alkalinity of the surface water layers and an increase in calcium concentration at the bottom were noted.

2018 ◽  
Vol 63 ◽  
pp. 00017
Author(s):  
Michał Lupa ◽  
Katarzyna Adamek ◽  
Renata Stypień ◽  
Wojciech Sarlej

The study examines how LANDSAT images can be used to monitor inland surface water quality effectively by using correlations between various indicators. Wigry lake (area 21.7 km2) was selected for the study as an example. The study uses images acquired in the years 1990–2016. Analysis was performed on data from 35 months and seven water condition indicators were analyzed: turbidity, Secchi disc depth, Dissolved Organic Material (DOM), chlorophyll-a, Modified Normalized Difference Water Index (MNDWI), Normalized Difference Water Index (NDWI) and Normalized Difference Vegetation Index (NDVI). The analysis of results also took into consideration the main relationships described by the water circulation cycle. Based on the analysis of all indicators, clear trends describing a systematic improvement of water quality in Lake Wigry were observed.


2016 ◽  
Vol 63 (3) ◽  
pp. 109-116
Author(s):  
Biljana Andjelski-Radičević ◽  
Maja Milošević ◽  
Ivan Dožić

Abstract Introduction Saliva is a complex secretion, which plays an important role in maintenance of oral health. Analysis of saliva is fast, simple and non-invasive, and it is increasingly used as a biological sample for determination of various biochemical markers. The aim was to determine the influence of unstimulated saliva collection methods for measuring electrolytes concentration (sodium, potassium, calcium), pH and buffer capacity of saliva in healthy subjects. Material and methods 30 healthy subjects, males and females, aged 18 to 20 years, without oral and systemic diseases were included in the study. Unstimulated saliva samples were taken using a special tube (Salivette) and via direct spitting into the test tube. The concentrations of sodium and potassium were determined by flame emission photometry while spectrophotometry was used for calcium concentration. For the analysis of pH value of saliva pH-meter was used, while saliva buffer capacity was determined by titration with HCl (0.005 mol/L). Results The level of sodium in unstimulated saliva collected in test tubes was 8.43 ± 3.92 mmol/L and in special tubes 7.90 ± 4.33 mmol/L. Potassium level in unstimulated saliva collected in test tubes was 13.62 ± 0.99 mmol/L while in special tubes it was 13.54 ± 0.94 mmol/L. Mean values of sodium and potassium in unstimulated saliva didn’t show statistically significant difference in their concentrations between the two methods of collecting saliva. In contrast to these electrolytes, calcium concentration was higher in the samples of saliva collected with special tubes (2.04 ± 1.05 mmol/L) compared to the samples taken by direct spitting into the test tube (1.38 ± 1.18 mmol/L) with statistically significant difference (p < 0.05). By analyzing the pH of unstimulated saliva it was found that the average pH value of saliva collected with special tubes was 7.05 ± 0.32, and after direct spitting into test tubes it was 7.35 ± 0.41. Buffer capacity of saliva in healthy subjects was lower after taking with special tubes (5.18 ± 0.74) compared to test tubes (5.36 ± 0.85), but without statistical difference. Conclusion Unstimulated saliva collecting methods using cotton pads (salivette) and direct spitting in the test tube did not affect the value of pH, buffer capacity, the concentrations of sodium and potassium, but affected the concentration of calcium in saliva from healthy subjects.


1970 ◽  
Vol 64 (1) ◽  
pp. 150-158 ◽  
Author(s):  
S. Pors Nielsen

ABSTRACT Intravenous infusion of isotonic magnesium chloride into young cats with a resultant mean plasma magnesium concentration of 7.7 meq./100 g protein was followed by a significant lowering of the plasma calcium concentration in 90 minutes. The rate of decrease of plasma calcium is consistent with the hypothesis that calcitonin is released by magnesium in high concentrations. There was no decrease in the plasma calcium concentration in cats of the same weight thyroparathyroidectomized 60 min before an identical magnesium chloride infusion or an infusion of isotonic sodium chloride at the same flow rate. The hypercalciuric effect of magnesium could not account for the hypocalcaemic effect of magnesium. Plasma magnesium concentration during magnesium infusion into cats with an intact thyroid-parathyroid gland complex was slightly, but not significantly higher than in acutely thyroparathyroidectomized cats.


2018 ◽  
Author(s):  
Julia Steele ◽  
◽  
Marissa Louise Mayfield ◽  
Morgan Rasmussen ◽  
Samuel Mutiti ◽  
...  

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4720
Author(s):  
Arlindo César Matias Pereira ◽  
Helison de Oliveira Carvalho ◽  
Danna Emanuelle Santos Gonçalves ◽  
Karyny Roberta Tavares Picanço ◽  
Abrahão Victor Tavares de Lima Teixeira dos dos Santos ◽  
...  

This study aimed to evaluate and compare the effects of co-treatment with purified annatto oil (PAO) or its granules (GRA, Chronic®) with that of testosterone on the orchiectomy-induced osteoporosis in Wistar rats. After surgery, rats were treated from day 7 until day 45 with testosterone only (TES, 7 mg/kg, IM) or TES + PAO or GRA (200 mg/kg, p.o.). The following parameters were evaluated: food/water intake, weight, HDL, LDL, glucose, triglycerides (TG), total cholesterol (TC), alkaline phosphatase levels, blood phosphorus and calcium contents, femur weight, structure (through scanning electron microscopy), and calcium content (through atomic absorption spectrophotometry). Our results show that orchiectomy could significantly change the blood lipid profile and decrease bone integrity parameters. Testosterone reposition alone could improve some endpoints, including LDL, TC, bone weight, and bone calcium concentration. However, other parameters were not significantly improved. Co-treatment with PAO or GRA improved the blood lipid profile and bone integrity more significantly and improved some endpoints not affected by testosterone reposition alone (such as TG levels and trabeculae sizes). The results suggest that co-treatment with annatto products improved the blood lipid profile and the anti-osteoporosis effects of testosterone. Overall, GRA had better results than PAO.


Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 987
Author(s):  
Mana Raj Rai ◽  
Amnat Chidthaisong ◽  
Chaiwat Ekkawatpanit ◽  
Pariwate Varnakovida

The Himalayas, especially the Everest region, are highly sensitive to climate change. Although there are research works on this region related to cryospheric work, the ecological understandings of the alpine zone and climate impacts are limited. This study aimed to assess the changes in surface water including glacier lake and streamflow and the spatial and temporal changes in alpine vegetation and examine their relationships with climatic factors (temperature and precipitation) during 1995–2019 in the Everest region and the Dudh Koshi river basin. In this study, Landsat time-series data, European Commission’s Joint Research Center (JRC) surface water data, ECMWF Reanalysis 5th Generation (ERA5) reanalysis temperature data, and meteorological station data were used. It was found that the glacial lake area and volume are expanding at the rates of 0.0676 and 0.0198 km3/year, respectively; the average annual streamflow is decreasing at the rate of 2.73 m3/s/year. Similarly, the alpine vegetation greening as indicated by normalized difference vegetation index (NDVI) is increasing at the rate of 0.00352 units/year. On the other hand, the annual mean temperature shows an increasing trend of 0.0329 °C/year, and the annual precipitation also shows a significant negative monotonic trend. It was also found that annual NDVI is significantly correlated with annual temperature. Likewise, the glacial lake area expansion is strongly correlated with annual minimum temperature and annual precipitation. Overall, we found a significant alteration in the alpine ecosystem of the Everest region that could impact on the water–energy–food nexus of the Dudh Koshi river basin.


Author(s):  
Constantin Bulimaga ◽  
◽  
Corina Certan ◽  

Regardless of the fact that both urban ecosystems studied – Orhei and Telenești – have purification stations, they are still an essential source of surface water pollution. The aqueous soil extract (Telenești) has a pH value of 8 up to 9.8 due to the high content of calcium and potassium in the soil, due to the fact that the area under investigation has a specific character caused by the spread of solonetz-type soils, solonized chernozems, and salinated soils. The anthropogenic impact in urban ecosystems produces an imbalance in the ratio of spontaneous species and ruderal and ruderal-segetal species. The number of spontaneous species is the indicator of the degree of anthropization in urban ecosystems. Urban ecosystems have a major impact on the environment.


Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2699 ◽  
Author(s):  
Jian Li ◽  
Liqiao Tian ◽  
Qingjun Song ◽  
Zhaohua Sun ◽  
Hongjing Yu ◽  
...  

Monitoring of water quality changes in highly dynamic inland lakes is frequently impeded by insufficient spatial and temporal coverage, for both field surveys and remote sensing methods. To track short-term variations of chlorophyll fluorescence and chlorophyll-a concentrations in Poyang Lake, the largest freshwater lake in China, high-frequency, in-situ, measurements were collected from two fixed stations. The K-mean clustering method was also applied to identify clusters with similar spatio-temporal variations, using remote sensing Chl-a data products from the MERIS satellite, taken from 2003 to 2012. Four lake area classes were obtained with distinct spatio-temporal patterns, two of which were selected for in situ measurement. Distinct daily periodic variations were observed, with peaks at approximately 3:00 PM and troughs at night or early morning. Short-term variations of chlorophyll fluorescence and Chl-a levels were revealed, with a maximum intra-diurnal ratio of 5.1 and inter-diurnal ratio of 7.4, respectively. Using geostatistical analysis, the temporal range of chlorophyll fluorescence and corresponding Chl-a variations was determined to be 9.6 h, which indicates that there is a temporal discrepancy between Chl-a variations and the sampling frequency of current satellite missions. An analysis of the optimal sampling strategies demonstrated that the influence of the sampling time on the mean Chl-a concentrations observed was higher than 25%, and the uncertainty of any single Terra/MODIS or Aqua/MODIS observation was approximately 15%. Therefore, sampling twice a day is essential to resolve Chl-a variations with a bias level of 10% or less. The results highlight short-term variations of critical water quality parameters in freshwater, and they help identify specific design requirements for geostationary earth observation missions, so that they can better address the challenges of monitoring complex coastal and inland environments around the world.


2013 ◽  
Vol 16 (3) ◽  
pp. 106-119
Author(s):  
Phu Ly Sy Nguyen ◽  
Nguyen Duc Do ◽  
Hien Thi To

Residual levels of organochlorine and organophosphorus pesticides in surface water in some agricultural areas at Ho Chi Minh City were investigated in 2012. Four organophosphorus pesticides including Malathion, Parathion, Ethion and Trithion and seven organochlorine pesticides including Alpha - HCH, beta-HCH, gammaHCH, aldrin, Heptachlor – epoxide, AlphaEndosulfan and Endosulfan-sulfate were determined in the surface water in four dicstricts : Binh Chanh, Hoc Mon, Cu Chi and Binh Tan using gas chromatographic method with electron capture detector (GCECD). The results showed that residues of pesticide were found with high concentrations in surface water in agricultural areas and pesticide residues changed depending on growth stages of crops. The concentration and distribution of pesticides were different in the water samples at different sites. Residues of pesticides such as Parathion, Ethion and Trithion were detected in surface water although these chemicals had been banned.


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