scholarly journals Estimation of Nutrient Loads With the Use of Mass-balance and Modelling Approaches on the Wełna River Catchment Example (Central Poland)

2022 ◽  
Author(s):  
Damian Bojanowski ◽  
Paulina Orlińska-Woźniak ◽  
Paweł Wilk ◽  
Ewa Szalińska
Keyword(s):  
Mass Balance ◽  
Nutrient Loads ◽  
Nitrogen And Phosphorus ◽  
Policy Makers ◽  
Nutrient Sources ◽  
Mass Balance Method ◽  
Hybrid Solution ◽  
Different Sources ◽  
Insight Into

Abstract Nitrogen and phosphorus budgeting is considered to be a useful tool for policy makers and stakeholders when dealing with nutrient contamination issues. Although a variety of budgeting approaches have been employed in countries affected by this problem, the direct comparison of possible options for the same area is quite limited. The current study offers a detailed insight into the estimations of nutrient loads and their distribution between different sources for a middle-sized agricultural catchment, with the use of two approaches: mass balance method and SWAT modelling. As a result of their comparison, both methods revealed similar contributions of analysed nutrient sources, although the absolute loads were heterogeneous, which stems from drawbacks related to the quality of the monitoring data, the performance of the model and omission of some catchment processes. However, in light of the performed comparison, we suggest a hybrid solution, combining the best features of both approaches.

Statistical modelling of riverine nutrient sources and retention in the Lake Peipsi drainage basin

2005 ◽  
Vol 51 (3-4) ◽  
pp. 309-317 ◽  
Author(s):  
A. Vassiljev ◽  
P. Stålnacke
Keyword(s):  
River Basin ◽  
Agricultural Land ◽  
Drainage Basin ◽  
Statistical Modelling ◽  
Point Sources ◽  
Simultaneous Estimation ◽  
Nutrient Loads ◽  
Nitrogen And Phosphorus ◽  
Lake Peipsi ◽  
Nutrient Sources

Implementation of the Water Framework Directive calls for methodologies and tools to quantify nutrient losses from diffuse sources at a river basin district scale. Here, we examine the possibility of using a statistical model for source apportionment and retention of nutrients in a large transboundary drainage basin (44,000 km2). The model approach uses non-linear regression for simultaneous estimation of e.g. source strength, i.e. export coefficients to surface waters, for the different specified land-use or soil categories and retention coefficients for pollutants in a drainage basin. The model was tested on data from 26 water quality stations with corresponding sub-basin data, i.e., land cover, point sources and atmospheric deposition, from the Estonian part of the Lake Peipsi drainage basin. The model showed that it was statistically possible to derive reliable export coefficients (i.e. unit-area loads) for nitrogen on agricultural land and forests. Moreover, it was shown with simple empirical functions that lake retention was approximately 30-35% for both nitrogen and phosphorus and that the riverine retention was low for both nitrogen and phosphorus (approx. 10%). Results show that the MESAW model is a simple and powerful tool for simultaneous estimation of sources and retention of nutrient loads in a river basin.

Waste stabilization ponds in France: a report on fifteen years experience

1995 ◽  
Vol 31 (12) ◽  
pp. 91-101 ◽  
Author(s):  
Y. Racault ◽  
C. Boutin ◽  
A. Seguin
Keyword(s):  
Load Level ◽  
Organic Load ◽  
Nitrogen And Phosphorus ◽  
Waste Stabilization Ponds ◽  
Sewerage System ◽  
System Type ◽  
Stabilization Ponds ◽  
Waste Stabilization ◽  
Output Load

In 1992, a survey was conducted on the performance of waste stabilization ponds in France. The data selected come from a sample of 178 ponds, with an average capacity of 600 p.e., throughout France. For each plant, one or several input--output load measurements over a 24-h period are available. The average organic load level received is approximately 25 kg BOD/ha.d, representing 50% of the nominal load. The quality of the treated water is presented based on the type of sewerage system feeding the ponds. The results appear dispersed, however; in 70% of the cases the concentrations in COD and BOD on filtered samples are under 120 mg/l and 40 mg/l, respectively, and the concentration in TSS under 120 mg/l (discharge standards in France for waste stabilization ponds). The reductions in nitrogen and phosphorus nutrients are on average from 60% to 70%. The influence of different parameters (sewerage system type, organic load, season, age of plant, etc.) was studied. The results appear noticeably worse when the ponds receive wastewater from a strictly separate sewerage system.

Attitudes of Elderly People in the South Moravian Region to Further Education

2014 ◽  
Vol 4 (2) ◽  
pp. 54-78
Author(s):  
Petr Adamec ◽  
Marián Svoboda
Keyword(s):  
Quality Of Life ◽  
Elderly People ◽  
Further Education ◽  
The South ◽  
The Third ◽  
Interesting Insight ◽  
Survey Results ◽  
Insight Into ◽  
Demographic Features

This paper deals with the results of sociological survey focused on identification of the attitudes of elderly people to further education. The research was carried out in September 2010. Experience of elderly people with further education, their readiness (determination) for further education as well as their motivation and barriers in further education were also subjects of this research. Detecting elderly population’s awareness of universities of the third age and finding out their further education preferences were an integral part of the research. Research sample consisted of citizens over 55 years living in the South Moravian region. The survey results are structured by socio-demographic features e.g.: age, sex, educational attainment etc. and provide an interesting insight into the attitudes of the target group to one of the activities that contributes to improvement of their quality of life.

scholarly journals The use of mathematical modelling to analyse the process of mixing waters from different sources in water supply system

2018 ◽  
Vol 59 ◽  
pp. 00025
Author(s):  
Agnieszka Szuster – Janiaczyk ◽  
Rafał Brodziak ◽  
Jędrzej Bylka
Keyword(s):  
Mathematical Modeling ◽  
Water Quality ◽  
Quality Criteria ◽  
Supply System ◽  
Network Control ◽  
Quality Of Water ◽  
Water Mains ◽  
Different Sources ◽  
Mixing Water

One of the processes that significantly determines the quality of water to consumers is the process of mixing water from different sources in the water mains. Put to the network two or more chemically and biologically stable waters may result in the formation of water that will be deprived of these features. This article presents the german guidelines for analysing water quality for mixing waters from different sources, in various proportions. Then performed an analysis of utility the mathematical models,including quality criteria, for use in network control. An IT tool has been developed to manage selected water quality processes using mathematical modeling. The basis for implementing the tool was a network model created in Epanet integrated with the Matlab.

scholarly journals Comparisons among rainbow trout, Oncorhynchus mykiss, populations of maternal transcript profile associated with egg viability

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gregory M. Weber ◽  
Jill Birkett ◽  
Kyle Martin ◽  
Doug Dixon ◽  
Guangtu Gao ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Egg Quality ◽  
Transcript Abundance ◽  
Differentially Expressed ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Analysis Group ◽  
Maternal Transcripts ◽  
Single Batch ◽  
Insight Into

Abstract Background Transcription is arrested in the late stage oocyte and therefore the maternal transcriptome stored in the oocyte provides nearly all the mRNA required for oocyte maturation, fertilization, and early cleavage of the embryo. The transcriptome of the unfertilized egg, therefore, has potential to provide markers for predictors of egg quality and diagnosing problems with embryo production encountered by fish hatcheries. Although levels of specific transcripts have been shown to associate with measures of egg quality, these differentially expressed genes (DEGs) have not been consistent among studies. The present study compares differences in select transcripts among unfertilized rainbow trout eggs of different quality based on eyeing rate, among 2 year classes of the same line (A1, A2) and a population from a different hatchery (B). The study compared 65 transcripts previously reported to be differentially expressed with egg quality in rainbow trout. Results There were 32 transcripts identified as DEGs among the three groups by regression analysis. Group A1 had the most DEGs, 26; A2 had 15, 14 of which were shared with A1; and B had 12, 7 of which overlapped with A1 or A2. Six transcripts were found in all three groups, dcaf11, impa2, mrpl39_like, senp7, tfip11 and uchl1. Conclusions Our results confirmed maternal transcripts found to be differentially expressed between low- and high-quality eggs in one population of rainbow trout can often be found to overlap with DEGs in other populations. The transcripts differentially expressed with egg quality remain consistent among year classes of the same line. Greater similarity in dysregulated transcripts within year classes of the same line than among lines suggests patterns of transcriptome dysregulation may provide insight into causes of decreased viability within a hatchery population. Although many DEGs were identified, for each of the genes there is considerable variability in transcript abundance among eggs of similar quality and low correlations between transcript abundance and eyeing rate, making it highly improbable to predict the quality of a single batch of eggs based on transcript abundance of just a few genes.

scholarly journals Quantity and quality of childcare and children’s educational outcomes

2021 ◽  
Author(s):  
Jo Blanden ◽  
Emilia Del Bono ◽  
Kirstine Hansen ◽  
Birgitta Rabe
Keyword(s):  
School Achievement ◽  
Additional Term ◽  
Publicly Funded ◽  
Highly Qualified ◽  
Policy Makers ◽  
Quality Rating ◽  
Quality Of Childcare ◽  
The Impact ◽  
School Records

AbstractPolicy-makers wanting to support child development can choose to adjust the quantity or quality of publicly funded universal pre-school. To assess the impact of such changes, we estimate the effects of an increase in free pre-school education in England of about 3.5 months at age 3 on children’s school achievement at age 5. We exploit date-of-birth discontinuities that create variation in the length and starting age of free pre-school using administrative school records linked to nursery characteristics. Estimated effects are small overall, but the impact of the additional term is substantially larger in settings with the highest inspection quality rating but not in settings with highly qualified staff. Estimated effects fade out by age 7.

scholarly journals Introduction to the special issue: multiple jobholding in Europe

2021 ◽  
Vol 27 (2) ◽  
pp. 141-147
Author(s):  
Wieteke Conen ◽  
Karin Schulze Buschoff
Keyword(s):  
Labour Market ◽  
Social Protection ◽  
Special Issue ◽  
Clear Trend ◽  
Policy Makers ◽  
Quality Of Work ◽  
Labour Market Flexibility ◽  
Employment Situation ◽  
Over Time

In a number of European countries there is a clear trend towards increased multiple jobholding. As things stand, however, little is known about the structure and the potential consequences of this increase, notably in terms of quality of work and social protection. This special issue focuses on contemporary forms of multiple jobholding in Europe. Have the structure, nature and dynamics of multiple jobholding changed over time? What are the roles of labour market flexibility, technological change and work fragmentation in the development of multiple jobholding? And do multiple jobholders benefit from similar and adequate employment terms, conditions and protections compared with single jobholders, or are they worse off as a consequence of their (fragmented) employment situation? What implications do these findings have for unions, policy-makers and the regulation of work? The collection of articles in this special issue adds to the literature on emerging forms of employment in the digital age and challenges for social protection, also in light of the COVID-19 pandemic. This introduction initiates a discussion of central debates on multiple jobholding and presents a synopsis of the articles in this issue.

A Study on the Mineral Depletion of the Foods Available to us as a Nation over the Period 1940 to 1991

2003 ◽  
Vol 17 (2) ◽  
pp. 85-115 ◽  
Author(s):  
David Thomas
Keyword(s):  
Mineral Content ◽  
Dietary Habits ◽  
Medical Research Council ◽  
Significant Loss ◽  
King's College ◽  
Compare And Contrast ◽  
Insight Into ◽  
Mineral Constituents ◽  
Mineral Depletion

In 1927 a study at King's College, University of London, of the chemical composition of foods was initiated by Dr McCance to assist with diabetic dietary guidance. The study evolved and was then broadened to determine all the important organic and mineral constituents of foods, it was financed by the Medical Research Council and eventually published in 1940. Over the next 51 years subsequent editions reflected changing national dietary habits and food laws as well as advances in analytical procedures. The most recent (5th Edition) published in 1991 has comprehensively analysed 14 different categories of foods and beverages. In order to provide some insight into any variation in the quality of the foods available to us as a nation between 1940 and 1991 it was possible to compare and contrast the mineral content of 27 varieties of vegetable, 17 varieties of fruit, 10 cuts of meat and some milk and cheese products. The results demonstrate that there has been a significant loss of minerals and trace elements in these foods over that period of time. It is suggested that the results of this study cannot be taken in isolation from recent dietary, environmental and disease trends. These trends are briefly mentioned and suggestions are made as to how the deterioration in the micronutrient quality of our food intake may be arrested and reversed.

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