scholarly journals Hellenic Karst Aquifers Vulnerability Approach Using Factor Analysis: The Example of the Louros Karst Aquifers

Geosciences ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 417 ◽  
Author(s):  
Konstantina Katsanou

The karst aquifers of the Hellenic territory display high vulnerability that is related to the existence of the epikarst zone. If present, the epikarst zone regulates the vertical movement of the groundwater, which results in the chemical pollutants staying longer within it, thus facilitating the inactivation of the microbial loads. The Hellenic karst is well developed; it displays high hydraulic conductivity, relatively large storage, and the characteristics of an important water reservoir. Although its porosity was calculated to be between 0.005–8%, the statistical processing of the springs’ discharge time series points to an increased storage. The increased storage was attributed to the presence of the epikarst zone, which regulates the water movement to the underlying formations, and finally to its discharge from the karst system through springs. In these areas, the influence of nitrogen compounds on the water quality is evident. The presence of cyanobacteria and toxic substances at concentrations that are too high for fresh, flowing waters whose temperature does not exceed 17 °C advocates the role of nutrients, even at concentrations that do not exceed the maximum permissible limits of drinking water. In mountainous areas, where agriculture is limited, the presence of these compounds is attributed to heavily polluting land uses. The impact of such uses became apparent from the application of factor analysis, which not only highlighted their contribution to the overall groundwater quality, but also determined their geographical distribution and origin. From the above, it becomes evident that there is a need for protection of the karst aquifers, and investigation of their vulnerability mechanisms. The Hellenic karst, which is expected to cover the drinking water needs in the near future, proves to be very vulnerable to any kind of pollution.

Author(s):  
Petra Nováková

The aim of the work was to elaborate and evaluate the water quality of water reservoir Vranov nad Dyjí. Fresh water was sampled in five different locations of the reservoir (three important tributaries, dam and water captation locality). Ten, the most essential water quality indicators were selected. From the point of view of water quality indicators complexity the most integrated samples were taken in the water captation locality (period 1984 – 2002). At other locations, there were missing dates from the eightieth, but their volume was sufficient for statistical processing.Correlation analyses for the individual locations and dimensions were done as so as determination coefficients for all localities during the time period of 1994 – 2002. The results demonstrate very good allocation of the water captation from the point of view of the water flow.Multiples and factor analysis was done for the period of 1984 – 2002 in the locality Jelení zátoka where the object of water captation is situated. The results of the analysis are nine factors, which influence the water quality of the reservoir. From the point of view of the importance three factors were interpreted.The analyses and results are part of my Ph.D. thesis. The results will be used for other evaluations of the water quality in the reservoir and tributaries, for activities in the catchment’s area and for proposal processing other zones of second level of protected areas.


Author(s):  
Dung A. Dao ◽  
Son H. Tran ◽  
Huyen T. T. Dang ◽  
Viet-Anh Nguyen ◽  
Viet Anh Nguyen ◽  
...  

Abstract In many areas of the world, rainwater has been collected and consumed by people. Our research aims to assess the use of rainwater and the impact of operation and maintenance activities of the rainwater system on drinking water quality in rural areas where there is no access to a public drinking water system. Through the questionnaire, direct visits, interviews and sampling of water at surveyed households (HHs), it was found that 100 and 98% of surveyed HHs used rainwater for drinking and cooking, respectively. Nearly, 80% of them were aware of the necessity of frequent reservoir cleaning as well as first-flush removal. Cleaning the water reservoir had a significant impact on water quality, in particular the total dissolved solids (p-value < 0.05). The use of strainers and more frequency of cleaning the catchment roofs and gutters would make the lower turbidity in water. However, the use of strainers would reduce the dissolution of oxygen in the reservoirs. A recommendation on the frequency of maintaining the rainwater harvesting systems was proposed after assessment of the operation and maintenance behaviors at surveyed HHs.


1998 ◽  
Vol 32 (11) ◽  
pp. 3293-3306 ◽  
Author(s):  
Michael A. Anderson ◽  
Mic H. Stewart ◽  
Marylynn V. Yates ◽  
Charles P. Gerba

2020 ◽  
Vol 5 (6) ◽  
pp. 218-223
Author(s):  
N. M. Onul ◽  
◽  
E. M. Biletska ◽  
T. A. Holovkova

Among the xenobiotics of diverse nature, heavy metals are especially dangerous for the human reproductive system in case of excessive intake. Cadmium, which is one of the most common toxic substances for the environment and production, can pose a potential threat to human health. An increasing amount of cadmium in the environmental objects and in nutrition is believed to be related to a poor semen quality. The purpose of the study was to determine the impact of cadmium on the reproductive potential of men who live in ecologically contrasting conditions. Material and methods. Clinical and hygienic assessment of the reproductive health was carried out among 2 experimental groups: the 1st group consisted of fertile men living in the city of Dnipro (62 respondents), the 2nd group included men with normal fertility living in the control city (37 respondents). To determine the cadmium concentration, venous blood samples and ejaculate were selected according to the standard methods. Biological samples were transferred to aliquots, frozen and stored at -20 ° C until analysis. The research was carried out using inversion voltammetry on the device AVA-2. Statistical processing of the results was carried out using statistical software packages of statistical analysis Statistica v.6.1 (StatsoftInc., США, licence NAJAR909E415822FA), Microsoft Excel. Results and discussion. Cadmium content in the blood and in the sperm of the fertile men of industrial city 1.3-5.8 times higher than the results of research in the control city and literature data. Differences between the cadmium content in the blood and semen of fertile men was shown to be unlikely, suggesting that the hematotesticular barrier is insufficient to protect the male reproductive organs from the toxic effects of the metal. The ejaculate in the fertile men of the studied cities is characterized by normosospermia and meets the standards. However in the residents of the industrial city the ejaculate quality indices were mostly at the lower level of the norm and were significantly worse than in the residents of the control city. Cadmium contained in male biosubstrates affect the hormonal status and quality of semen. Conclusion. Violations of spermatogenesis can serve as a rapidly-responding and reliable criterion for assessing the adaptation and maladaptation processes of men under the influence of xenobiotics of the environment, in particular cadmium. In this case, the markers of influence are the total number of sperm in the ejaculate, their concentration, mobility and the number of pathological forms, semen viscosity


2013 ◽  
Vol 67 (8) ◽  
pp. 1748-1756 ◽  
Author(s):  
Xiaodan Jin ◽  
Yiliang He ◽  
Bo Zhang ◽  
Younas Hassan ◽  
Kirumba George

The impact of sulfate (SO42−) and chloride (Cl−) on phosphorus (P) release from sediment in the drinking water reservoir of Yangtze River Estuary was studied systematically. A significant correlation between sodium (Na+), Cl−, SO42− and total P was found, suggesting that P was directly or indirectly associated with these ions. SO42− and Cl− were important factors that had an impact on P release from the sediment. The results showed that both sulfate and chloride enhanced phosphorus release from sediment. In the sulfate treatment, the decrease of organic phosphorus (OP) suggested that the mineralization of OP enhanced P release from sediment. Phosphonate was the main factor affecting the P release under sulfate condition. In chloride treatment, the sediment composition of iron (Fe), aluminum (Al), calcium (Ca) and magnesium (Mg) increased. The P fractions of Fe/Al-P, Ca-P and OP in sediment also increased. However, the increase of P was unstable after chloride treatment and was easy to release under disturbance. In this study, it was observed that sulfate and chloride could increase the risk of eutrophication in the Yangtze River Estuary drinking water reservoir.


2005 ◽  
Vol 3 (4) ◽  
pp. 453-468 ◽  
Author(s):  
R. S. Signor ◽  
D. J. Roser ◽  
N. J. Ashbolt ◽  
J. E. Ball

Concentrations of microbiological contaminants in streams increase during rainfall-induced higher flow ‘event’ periods as compared to ‘baseflow’ conditions. If the stream feeds a drinking water reservoir, such periods of heightened pathogen loads may pose a challenge to the water treatment plant and subsequently a health concern to water consumers downstream. In order to manage this risk, it is desirable to first quantify the differences in surface water quality between baseflow and event conditions. The Event Mean Concentration (EMC) is a flow-weighted average concentration of a contaminant over the duration of a single event, proposed here as a standard parameter for quantifying the net effect of events on microbial water quality. Application of the EMC concept was assessed using flow and quality data for several events from an urbanised catchment. Expected mean EMCs were significantly larger than expected mean baseflow concentrations (p-value≤0.012) for three microbial agents - Escherichia coli (13,000 [n = 7] v. 610 [n = 16] mpn/100 ml), Cryptosporidium (234 [n = 6] v. 51 [n = 16] oocysts/10 litres) and Campylobacter (48 [n = 5] v. 2.1 [n = 16] mpn/100 ml). These parameter estimates were complemented by estimating data variability and uncertainty in the form of second-order random variables. As such the results are in a format appropriate for potential use as components in probabilistic risk assessments evaluating the effect runoff events have on drinking water quality.


GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.


2007 ◽  
Author(s):  
Robert Orazem ◽  
Claire Hebenstreit ◽  
Daniel King ◽  
Lynda King ◽  
Arieh Shalev ◽  
...  

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