Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River
Abstract
We have assembled and assessed the statistical procedure which is capable to objectively explore influence of the Danube's major tributaries (the Rivers Tisa, Sava, and Velika Morava) to its eco-chemical status. Procedure contains several tests for measurement of central tendencies: one-way analysis of variance (ANOVA), repeated measures ANOVA, and non-parametric Kruskal-Wallis and Mann-Whitney tests. Various nuisance factors, (outliers, departures from normality, seasonality, and heteroscedasticity) which are present in large data bases, affect the objectivity of central tendency tests; therefore, it was important not only to estimate their robustness, but also to apply proper procedures for detection of the nuisance factors (Grubbs', generalized ESD-extreme Studentized deviate, Kolmogorov-Smirnov, Shapiro-Wilk, turning point, Wald-Wolfowitz runs, Kendall rank, and Levene's tests) and to mitigate their influence (outlier exclusion, Box-Cox, and logarithmic transformations). The analys...is of selected eco-chemical parameters: biological oxygen demand-5, chemical oxygen demand, UV extinction at 254 nm, dissolved oxygen, oxygen saturation, total dissolved solids, electrical conductivity, suspended matter, total phosphorus, phosphates, nitrates, ammonia, pH, total alkalinity, m-2p alkalinity, CO2, and temperature, was performed for 15 years period. The Tisa was the most polluted tributary, but its pollution load was not substantial enough to exceed the Danube self-purification potential. The City of Belgrade was also identified as serious pollution source. Assessment of assembled statistical procedure, which was based on the real environmental data, indicates that proposed tests are sufficiently robust to the observed level of nuisance factors with the exception of pronounced seasonality.
Keywords:
Danube / Belgrade / Tributary influence / ANOVA post hoc tests / Heteroscedasticity / Box-Cox transformations / Long-term monitoring programsSource:
Environmental Monitoring and Assessment, 2015, 187, 9Publisher:
- Springer, Dordrecht
Funding / projects:
- Geochemical investigations of sedimentary rocks - fossil fuels and environmental pollutants (RS-MESTD-Basic Research (BR or ON)-176006)
Note:
- Peer-reviewed manuscript: https://cherry.chem.bg.ac.rs/handle/123456789/5758
DOI: 10.1007/s10661-015-4740-y
ISSN: 0167-6369
PubMed: 26239571
WoS: 000360313000007
Scopus: 2-s2.0-84938598310
Collections
Institution/Community
Hemijski fakultet / Faculty of ChemistryTY - JOUR AU - Ilijević, Konstantin AU - Obradović, Marko AU - Jevremovic, Vesna AU - Gržetić, Ivan PY - 2015 UR - https://cherry.chem.bg.ac.rs/handle/123456789/1956 AB - We have assembled and assessed the statistical procedure which is capable to objectively explore influence of the Danube's major tributaries (the Rivers Tisa, Sava, and Velika Morava) to its eco-chemical status. Procedure contains several tests for measurement of central tendencies: one-way analysis of variance (ANOVA), repeated measures ANOVA, and non-parametric Kruskal-Wallis and Mann-Whitney tests. Various nuisance factors, (outliers, departures from normality, seasonality, and heteroscedasticity) which are present in large data bases, affect the objectivity of central tendency tests; therefore, it was important not only to estimate their robustness, but also to apply proper procedures for detection of the nuisance factors (Grubbs', generalized ESD-extreme Studentized deviate, Kolmogorov-Smirnov, Shapiro-Wilk, turning point, Wald-Wolfowitz runs, Kendall rank, and Levene's tests) and to mitigate their influence (outlier exclusion, Box-Cox, and logarithmic transformations). The analysis of selected eco-chemical parameters: biological oxygen demand-5, chemical oxygen demand, UV extinction at 254 nm, dissolved oxygen, oxygen saturation, total dissolved solids, electrical conductivity, suspended matter, total phosphorus, phosphates, nitrates, ammonia, pH, total alkalinity, m-2p alkalinity, CO2, and temperature, was performed for 15 years period. The Tisa was the most polluted tributary, but its pollution load was not substantial enough to exceed the Danube self-purification potential. The City of Belgrade was also identified as serious pollution source. Assessment of assembled statistical procedure, which was based on the real environmental data, indicates that proposed tests are sufficiently robust to the observed level of nuisance factors with the exception of pronounced seasonality. PB - Springer, Dordrecht T2 - Environmental Monitoring and Assessment T1 - Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River VL - 187 IS - 9 DO - 10.1007/s10661-015-4740-y ER -
@article{ author = "Ilijević, Konstantin and Obradović, Marko and Jevremovic, Vesna and Gržetić, Ivan", year = "2015", abstract = "We have assembled and assessed the statistical procedure which is capable to objectively explore influence of the Danube's major tributaries (the Rivers Tisa, Sava, and Velika Morava) to its eco-chemical status. Procedure contains several tests for measurement of central tendencies: one-way analysis of variance (ANOVA), repeated measures ANOVA, and non-parametric Kruskal-Wallis and Mann-Whitney tests. Various nuisance factors, (outliers, departures from normality, seasonality, and heteroscedasticity) which are present in large data bases, affect the objectivity of central tendency tests; therefore, it was important not only to estimate their robustness, but also to apply proper procedures for detection of the nuisance factors (Grubbs', generalized ESD-extreme Studentized deviate, Kolmogorov-Smirnov, Shapiro-Wilk, turning point, Wald-Wolfowitz runs, Kendall rank, and Levene's tests) and to mitigate their influence (outlier exclusion, Box-Cox, and logarithmic transformations). The analysis of selected eco-chemical parameters: biological oxygen demand-5, chemical oxygen demand, UV extinction at 254 nm, dissolved oxygen, oxygen saturation, total dissolved solids, electrical conductivity, suspended matter, total phosphorus, phosphates, nitrates, ammonia, pH, total alkalinity, m-2p alkalinity, CO2, and temperature, was performed for 15 years period. The Tisa was the most polluted tributary, but its pollution load was not substantial enough to exceed the Danube self-purification potential. The City of Belgrade was also identified as serious pollution source. Assessment of assembled statistical procedure, which was based on the real environmental data, indicates that proposed tests are sufficiently robust to the observed level of nuisance factors with the exception of pronounced seasonality.", publisher = "Springer, Dordrecht", journal = "Environmental Monitoring and Assessment", title = "Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River", volume = "187", number = "9", doi = "10.1007/s10661-015-4740-y" }
Ilijević, K., Obradović, M., Jevremovic, V.,& Gržetić, I.. (2015). Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River. in Environmental Monitoring and Assessment Springer, Dordrecht., 187(9). https://doi.org/10.1007/s10661-015-4740-y
Ilijević K, Obradović M, Jevremovic V, Gržetić I. Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River. in Environmental Monitoring and Assessment. 2015;187(9). doi:10.1007/s10661-015-4740-y .
Ilijević, Konstantin, Obradović, Marko, Jevremovic, Vesna, Gržetić, Ivan, "Statistical analysis of the influence of major tributaries to the eco-chemical status of the Danube River" in Environmental Monitoring and Assessment, 187, no. 9 (2015), https://doi.org/10.1007/s10661-015-4740-y . .