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Wyszukujesz frazę "pollution index" wg kryterium: Temat


Wyświetlanie 1-4 z 4
Tytuł:
Distribution of Trace Elements in Surface Water and Sediments from Warri River in Warri, Delta State of Nigeria
Autorzy:
Ama, Ibiam Ntachiobi
Nwajei, Godfry E.
Agbaire, P. O.
Powiązania:
https://bibliotekanauki.pl/articles/1114111.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Contamination
Trace elements
Warri River
pollution index
Opis:
The pollution of surface water and sediments by heavy metals has become a difficult thing to deal with due to their toxicity and accumulative behavior. The present study was undertaken to provide information on the concentrations and distribution of selected heavy metals in surface water and sediments from Warri River, and to compute a contamination/pollution index of heavy metals. Surface water and sediment samples were collected using standard methods and then analysed for nine trace metals. These metals were determined using a Flame Atomic Absorption Spectrophotometer – UNICAM 929. According to our results, the mean concentrations of the select metals in the sediments were higher than those of the surface water. The figures, however, varied significantly in the six sample locations (SW1–SW6). In the sediments, the highest mean concentration was of Fe (504.13 mg/kg) in location SW1, whereas in surface water, generally, the highest mean concentration was of Fe (1.23 mg/l). In other words, mean metal levels in the sediments exceeded those of surface water. This indicates that sediments are a sink for metal pollution loads. Computation of contamination/ pollution index in sediment matrix revealed that Cd moderately polluted the sediment, Zn, Fe, Ni slightly, yet significantly contaminated the sediment, while Cu, Cr and Mn very slightly contaminated the sediments. The mean values of metals in this present study were compared with other values reported by other researchers. The higher than normal metal values were attributed to anthropogenic wastes, runoff, refinery jetty and varied petroleum related activities in the area.
Źródło:
World News of Natural Sciences; 2017, 11; 65-82
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Galls on Alstonia scholaris leaves as air pollution indicator
Autorzy:
Talukdar, Partha
Das, Kaushiki
Dhar, Shrinjana
Talapatra, Soumendra Nath
Swarnakar, Snehasikta
Powiązania:
https://bibliotekanauki.pl/articles/1189972.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Automobile air pollution
gall formation
bioindicator plant
leaf morphology and anatomy
Air Pollution Index (API)
Alstonia scholaris
Opis:
Air pollution arises mainly from automobiles and industries is well known fact. Monitoring and detection by instrument cannot be possible everywhere however, indication from plant species by their alterations in leaf morphology and anatomy may be a suitable easy screening measurement. The present study aims to detect morphological features with special reference to gall quantification and anatomy of leaves of Alstonia scholaris R. Br., found in eastern Indian urban and suburban area that are exposed to vehicular emission. The results indicated alterations of leaf morphology along with length (L), breadth (B), L/B ratio and significantly increased (P < 0.001, 0.01 and 0.05) Air Pollution Index (API). It is concluded that vehicular emission can be monitored as an early indication through increased API in A. scholaris. Further research would be needed in relation to secondary metabolites alteration, biochemical and genetic parameters to know pollutant susceptibility as an indicator. In addition, anatomical abnormalities in gall formation as well as numbers were also pronounced in leaves exposed to various load of air pollution.
Źródło:
World Scientific News; 2016, 52; 181-194
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ecological risk assessment of heavy metals in soil developed on coastal marine sediment along coastal area in Anantigha, Calabar, Nigeria
Autorzy:
Aki, E. E.
Isong, I. A.
Powiązania:
https://bibliotekanauki.pl/articles/1076124.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ecological risk factor
geo-accumulation Index
heavy metal
pollution load index marine sediment
Opis:
Coastal areas in Anantigha are utilized as dumpsite for industrial and domestic wastes including effluent from local industries and inhabitants of the area despite their usage for crop cultivation. Thus, the present study was designed to assess the concentration, pollution load and ecological risk of heavy metal in Anantigha coastal area. Standard pollution indices such as contamination factor (Cf), degree of contamination, pollution load index (PLI), enrichment factor (EF), geo-accumulation index (Igeo) and ecological risk index were deployed to assess the level of heavy metals contamination in the area. The results showed that the sediment was acidic under dried conditions and low in conductivity. The mean concentration levels of all the heavy metals were lower than their mean background values except for Al. The orders of dominance for concentration of heavy metals were: Al>Fe>Mn>Cu>Zn (Station 1) and Al>Fe>Mn>Zn>Cu (Stations 2, 3 and 4). Analyzed data showed that the sediments in the area are contaminated with Al with Igeo result showing station 2 and 4 been moderately to heavily contaminated with Al while station 4 was heavily contaminated with aluminium. Station 1 had low degree of contamination, whereas station 2 and 4 had moderate degree of contamination, and station 3 showed considerable degree of contamination. The PLI result indicates unpolluted condition and the area were not enriched by the studied heavy metals as shown by EF values. Hence, the sediment in Anantigha coastal marine area was classified as having low ecological risk factor. However, the levels of these metals are not static; there is tendency for increase as a result of increased human input and activities. Hence, there is a need for regular soil testing.
Źródło:
World Scientific News; 2019, 116; 1-24
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heavy metal concentration and distribution in stream sediments of Ndongo River, Buea, Cameroon - environmental impact
Autorzy:
Tchounda, Teclaire
Mboudou, Germain Marie Monespérance
Agyingi, Christopher Mbaringong
Powiązania:
https://bibliotekanauki.pl/articles/1066167.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Buea
Heavy metal contamination
Igeo
Ndongo River
PLI
anthropogenic metal input
domestic waste
geochemical entity
pollution load index
stream sediments
Opis:
Thirty two active stream sediment samples were collected, panned and sieved from a 16km (500m spacing) section along Ndongo River, Buea. Sixteen of them were subjected to magnetic separation for the determination of heavy minerals under a microscope (KARL ZEISS IENA) and analyzed by XRF and AAS for As, Be, Cd, Co, Cu, Cr, Mo, Ni, Pb, Rb, Sb, Sc, Sn, Sr V, Zn, and Zr. The average element concentrations are 0.014, 64.45, 76.93, 94.52, 87.65, 147.79, 0.00, 77.00, 98.99, 40.37, 7.99, 24.70, 52.42, 1053.37, 285.46, 579.70 and 404.41ppm respectively. As (0.014 ppm) and Mo (0.001 ppm) are below l average concentrations in basalts while dispersed Be, Cd, Co, Cu, Cr, Ni, Pb, Sb, Sc, Sn, V, Zn values are mostly above tolerance limit in settlement areas and farmlands. Olivine with angular grains (1.5mm) and sub-hedral shape representing 10 vol. % is light green colored. Together with pyroxene (elongated, black colored with angular grains up to 0.7mm) are the most abundant minerals. Minor rutile with shiny luster is also present. R-mode factor analysis reveals Ni-Rb-V, Co–Cr–Pb–Zn, and Cu–Sr-Zr associations representing three geochemical entities related to agricultural (fertilizers) and settlement (domestic waste) areas. Correlation coefficients (r) vary from -0.84 (V, Sb) to 0.728 (Ni, Rb) and may indicate different sources of metal contamination. The calculated PLI (3.10 to 4.92) and Igeo (-7.37 to 9.18) of As, Be, Cd, Co, Cu, Cr, Mo, Ni, Pb, Rb, Sb, indicate metal pollution of River Ndongo sediments. The obtained classification is defined as low (As, Co, Cu, Cr, Mo, Ni, Sc, and V), partially (Co, Zn), moderately (Pb, Be) and highly to very highly (Sb, Sr, Cd) polluted. Natural and anthropogenic metal input assessment reveals that the dominantly basaltic lithologies in the area (pyroxene and olivine), the domestic and agricultural activities as well as urbanization processes of Buea are the main source of metal contamination.
Źródło:
World Scientific News; 2019, 131; 15-36
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

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