Application and evaluation of kriging and cokriging methods on groundwater depth mapping

Groundwater and water resources management play a key role in conserving the sustainable conditions in arid and semi-arid regions. Applying some techniques that can reveal the critical and hot conditions of water resources seem necessary. In this study, kriging and cokriging methods were evaluated for mapping the groundwater depth across a plain in which has experienced different climatic conditions (dry, wet, and normal) and consequently high variations in groundwater depth in a 12 year led in maximum, minimum, and mean depths. During this period groundwater depth has considerable fluctuations. Results obtained from geostatistical analysis showed that groundwater depth varies spatially in different climatic conditions. Furthermore, the calculated RMSE showed that cokriging approach was more accurate than kriging in mapping the groundwater depth though there was not a distinct difference. As a whole, kriging underestimated the real groundwater depth for dry, wet, and normal conditions by 5.5, 2.2, and 5.3%, while cokriging underestimations were 3.3, 2, and 2.2%, respectively; which showed the unbiasedness in estimations. Results implied that in the study area farming and cultivation in dry conditions needs more attention due to higher variability in groundwater depth in short distances compared to the other climate conditions. It is believed that geostatistical approaches are reliable tools for water resources managers and water authorities to allocate groundwater resources in different environmental conditions.     

Multivariate analysis of heavy metals concentrations in river estuary

Multivariate statistical techniques such as multivariate analysis of variance (MANOVA) and discriminant analysis (DA) were applied for analyzing the data obtained from two rivers in the Penang State of Malaysia for the concentration of heavy metal ions (As, Cr, Cd, Zn, Cu, Pb, and Hg) using a flame atomic absorption spectrometry (F-AAS) for Cr, Cd, Zn, Cu, Pb, As and cold vapor atomic absorption spectrometry (CV-AAS) for Hg. The two locations of interest with 20 sampling points of each location were Kuala Juru (Juru River) and Bukit Tambun (Jejawi River). MANOVA showed a strong significant difference between the two rivers in terms of heavy metal concentrations in water samples. DA gave the best result to identify the relative contribution for all parameters in discriminating (distinguishing) the two rivers. It provided an important data reduction as it used four parameters (Zn, Pb, Cd and Cr) affording 100% correct assignations. Results indicated that the two rivers were different in terms of heavy metals concentrations in water, and the major difference was due to the contribution of Zn. A negative correlation was found between discriminate functions (DF) and Cr and As, whereas positive correlation was exhibited with other heavy metals. Therefore, DA allowed a reduction in the dimensionality of the data set, delineating a few indicator parameters responsible for large variations in heavy metal concentrations. Correlation matrix between the parameters exhibited a strong evidence of mutual dependence of these metals.     

Contamination by organochlorine compounds in the edible tissue of four sturgeon species from the Caspian Sea (Iran)

This study focused on accumulation of organochlorine compounds (OCs), including dichloro-diphenyl-trichloroethanes (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and polychlorinated biphenyls (PCBs) accumulation in the muscle of four sturgeon (Persian sturgeon, Acipenser persicus; Stellate sturgeon, Acipenser stellatus; Ship sturgeon, Acipenser nudiventris and Beluga sturgeon, Huso huso) from the southern Caspian Sea. The DDT group was prominent in all of the sturgeon muscle tested constituting almost half or more of the total organochlorine content. Contaminant concentration generally followed this order: DDTs>PCBs>HCHs>HCB. The OCs concentrations in Beluga sturgeon (H. huso) were the highest and over four times higher than in the next highest species (A. nudiventris). From an ecotoxicological point of view, the concentrations of OCs in experimental fishes do not reflect a comparatively clean and pollution-free environment; however, results from this study shown that the inflow of organic pollutants into the Caspian Sea has been reduced when compared with prior studies. Levels of measured OCs in sturgeon were relatively low, but the level of some OCs in some of the specimens tested exceeded the guidelines for food; therefore, the maximum allowable daily consumption rate for sturgeon from this watershed may be limited by DDTs and PCBs content for high risk populations.     

Humanarzneimittel im aquatischen Ökosystem

Goal

In the Brandenburg State Office for the Environment an approach to assess the potential risk of drug residues in aquatic ecosystems has been developed based on an investigation of the consumption amounts in 1999 to identify or to exclude a potential environmental risk of important human drugs and further to define priority substances for monitoring programs in Brandenburg in the future.

Method

This assessment approach tested with 60 drug agents is based on an exposure estimation considering the main path for the entry human—waste water—sewage plant—surface water, on a substance specific analysis of effects and on an analysis of the environmental fate as compartment distribution, bioaccumulation and persistence.

Results

In Brandenburg surface waters the drug agent concentration for eight of the considered substances is supposed to be greater than 1 μg/l and for at least 13 of the considered substanoes the PNEC in aquatic ecosystems is assumed to be lower than 1 μg/l. A potential risk for the environment can be seen for the antibiotics Ciprofloxacin-HCl and Clarithromycin, the disinfectants Benzalkonium Chloride, Cocospropylendiaminguaniacetat, Glucoprotamine, Laurylpropylenediamine and Polyvidone-iodine, the sexual hormon Ethinylestradiol, the antidiabetic Metformin-HCl, the antiepileptic Carbamazepine and the lipid regulator Clofibrinic acid on the basis of effects because their PEC:PNEC-relation is about 1 or higher. For further 19 drug agents an environmental risk is to be assumed because of their environmental behaviour without support by ecotoxicological data at present.

Conclusion

Although there is only a small base of valid ecotoxicological data, this risk assessment shows that adverse effects in the aquatic environment by some drug agents cannot be excluded. However, it should be noted that this first assessment gives only a crude orientation. Appropriate test data are necessary to refine the assessment in future.     

Mapping farmers’ vulnerability to climate change and its induced hazards: evidence from the rice-growing zones of Punjab,Pakistan

Environmental Science and Pollution Research - In developing countries like Pakistan, agriculture constitutes the primary source of support for the majority of rural and the adjacent urban...     

Improving of photocatalytic activity of barium ferrate via bismuth and copper co-doping for degradation of paracetamol under visible light irradiation

Nanosized Ba_{1- x}Bi_xFe_1-xCu_xO₃（12–50 nm） with x values of 0, 0.01, 0.05, and 0.1 system was prepared using the Pechini method. Structural, morphological, surface and optical characterizations were performed for the prepared samples. Cubic phase was the predominant phase for the undoped BaFeO₃ and Bi and Cu co-doped BaFeO₃ samples. Minor phases of monoclinic Ba₂Fe₂O₅, orthorhombic BaFe     

On the sensitivity of the value of information to risk aversion in two-action decision problems

This paper discusses the sensitivity of the value of information to the risk aversion in two-action decision problems when the initial wealth is uncertain. We demonstrate that there is no general monotonicity between information value and the Arrow–Pratt risk aversion in this setting. We then show that monotonicity exists in the sense of Rubinstein’s measure of risk aversion when the lottery is independent of the initial wealth. Finally, we show that if the lottery is dependent on the initial wealth, then Ross’s measure of risk aversion is needed to characterize this monotonic relation. Our results explain the shape of the sensitivity analysis curve of the value of information to risk aversion and interpret various measures of risk aversion based on their monotonicity with information value.     

Efficient synthesis of α,β-unsaturated ketones with trans-selective Horner–Wadsworth–Emmons reaction in water

Organic reactions in aqueous media are being developed because water is environmentally benign. The Horner–Wadsworth–Emmons reaction is a modified Wittig reaction for the synthesis of α,β-unsaturated ketones and other conjugated compounds. Here we prepared high molecular weight ketones by the Horner–Wadsworth–Emmons reaction of dimethyl-2-oxopropylphosphonate and various aldehydes in water at room temperature. The product was precipitated during the reaction process and was separated readily by a simple filtration in 90–99 % yield.     

Cluster analysis of inorganic elements in particulate matter in the air environment of an equatorial urban coastal location

Concentrations of nine inorganic elements (Na, Zn, Ca, Fe, Ni, Mn, Cu, Cd and Al) in particulate matter (PM₁₀) in the air of an equatorial urban coastal location during 2009 were studied during summer and winter monsoon seasons using high-volume sampling techniques. Atomic absorption spectrophotometry was used to analyse the samples. The concentrations of most inorganic elements were higher during summer than winter, except for Cu and Zn. The main inorganic elements in PM₁₀ are Na, Zn and Ca. High concentrations of Na and Ca are due to marine aerosols. Analysis of enrichment factors showed that inorganic elements are from non-crustal sources. Cluster analysis identified five clusters in the summer and six in the winter: (1) PM₁₀–Ni, (2) Zn–Na, (3) Fe–Cu–Ca–Cd, (4) Mn and (5) Al for summer; and (1) PM₁₀, (2) Zn, (3) Fe–Ni, (4) Cu–Ca–Na–Cd, (5) Mn and (6) Al for winter. Combining both correlation and cluster analysis, it was found that Fe–Cu–Cd was from industry/vehicle emissions, Zn was from resuspended soil, Mn was from metallurgical processes, Ni was from a nearby power plant and Al was from crustal sources. Inorganic element concentrations could be a good indicator of local sources of PM₁₀.