The present work is aimed to extend the common POLLUTION indices into the fuzzy environment. For this purpose, a method was developed for converting the HEAVY METAL contamination in soil by fuzzy numbers. Then, the most commonly used POLLUTION indices are de ned as fuzzy numbers by applying the -cuts approach. To evaluate the degree of HEAVY METAL contamination in a speci c level, a degree of belonging was also suggested. The feasibility and e ectiveness of the proposed methods were also examined via an applied example.

The river Kabini which is tributary of Cauvery drains through industrial area at Nanjangud, Karnataka. Out of the sediment load carried by the river, 2micron the clay fraction was analyzed for total HEAVY METAL contents and advanced statistical techniques such as cluster analysis and correlation matrix were applied in order to investigate the source of HEAVY METAL concentration in the sediments. The river carries natural and anthropogenic pollutants, mainly HEAVY METAL concentration of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn which are released from industrial effluents, agricultural return flows and domestic sewage. The HEAVY METALs find their residence in the colloidal form in water and in 2micron clay fraction in the river bed sediments. Systematic sampling of the river bed sediments at predefined locations has revealed that the METAL accumulation is very close to normal and also beyond threshold limits. Compared with the maximum background values in Kabini river sediment, Pb was the highest in terms of contamination level, especially at point of influx of paper mill effluents, followed by Zn and Cu.

A total of 96 surface water samples collected from river Ganga in West Bengal during 2004-05 was analyzed for pH, EC, Fe, Mn, Zn, Cu, Cd, Cr, Pb and Ni. The pH was found in the alkaline range (7.21-8.32), while conductance was obtained in the range of 0.225-0.615 mmhos/cm. Fe, Mn, Zn, Ni, Cr and Pb were detected in more than 92% of the samples in the range of 0.025-5.49, 0.025-2.72, 0.012-0.370, 0.012-0.375, 0.001-0.044 and 0.001-0.250 mg/L, respectively, whereas Cd and Cu were detected only in 20 and 36 samples (0.001-0.003 and 0.003-0.032 mg/L). Overall seasonal variation was significant for Fe, Mn, Cd and Cr. The maximum mean concentration of Fe (1.520 mg/L) was observed in summer, Mn (0.423 mg/L) in monsoon but Cd (0.003 mg/L) and Cr (0.020 mg/L) exhibited their maximum during the winter season. Fe, Mn and Cd concentration also varied with the change of sampling locations. The highest mean concentrations (mg/L) of Fe (1.485), Zn (0.085) and Cu (0.006) were observed at Palta, those for Mn (0.420) and Ni (0.054) at Berhampore, whereas the maximum of Pb (0.024 mg/L) and Cr (0.018 mg/L) was obtained at the downstream station, Uluberia. All in all, the dominance of various HEAVY METALs in the surface water of the river Ganga followed the sequence: Fe>Mn>Ni>Cr>Pb>Zn>Cu>Cd. A significant positive correlation was exhibited for conductivity with Cd and Cr of water but Mn exhibited a negative correlation with conductivity.

Background: Evaluation of HEAVY METALs as toxic pollutants in environment has a significant importance in environmental POLLUTION studies. surficial sediments of water resources have a high potential in releasing HEAVY METALs to the upper water environment, hence sediment analysis presents guidelines to the authorities for monitoring the environmental systems.Methods: In this study, total and fractional concentration of eight HEAVY METALs (V, Ni, Cr, Cd, Zn, As, Fe, and Pb) were investigated along different sites of Anzali Wetland in Iran using bulk elemental analysis and sequential chemical extraction techniques respectively. Geoaccumulation index (Igeo) and POLLUTION Index (Ipoll) were computed and compared in different sites of the wetland, too.Results: Total concentration of METALs in sediment samples found to be in this order: Fe>As>Cr>Zn>Ni>V>Pb>Cd. The speciation data revealed that most METALs were bonded in lithogenous fractions that means no POLLUTION. Igeo results indicated that the wetland is moderately to highly polluted for Cd and As and Ipoll results showed that the wetland is moderately polluted for Pb and Cd were applied to METALs also to investigate on Igeo and Ipoll results. For V, Ni, Cr, Zn and Fe, cluster analysis confirmed both indices but for As and Pb it confirmed Igeo results.Conclusion: The results of the present study showed that the Anzali wetland is threatened by pollutants related to rivers entering it. So to preserve the environment of the Anzali wetland from deterioration, the main act is to prevent the discharge of wastewater to rivers entering it.

Human activities cause to the accumulation of HEAVY METALs in soil. Soil POLLUTION will significantly reduce environmental quality and affect human health. This study aimed to determine the concentration of some HEAVY METALs (Ni, Pb, Fe, Zn, Cr and Cd) and evaluate the effects of Kerman steel industry on concentration of soil HEAVY METALs. A total of 60 samples from the surface soil and a depth of 0-15 cm were collected at different distances from Kerman steel complex and analyzed with Atomic Absorption Spectroscopy (AAS). Some indices of POLLUTION including Contamination factor (Cf), POLLUTION index (PI), POLLUTION load index (PLI), POLLUTION Intensity index (Ipoll), Potential contamination index (Cp) were calculated to assess the levels of soil contamination. The Pearson correlation, principal component analysis (PCA), hierarchical clustering analysis (HCA) was used to determine the origin of pollutants. The results were showed the trend of HEAVY METAL concentration in the study area as Fe>Zn>Pb>Ni>Cr>Cd respectively. The maximum of studied indices was related to Pb and then Zn. Pearson correlation was showed that Zn with Cd and Pb with Cr had significant positive correlation. A PCA results of Cf index was stay Zn and Pb in the first cluster. In the other words, these two elements are more human origin. This study showed that the study area does not need to severe remedial action; however, continuous monitoring of environment is essential.

The effects of HEAVY METALs on soil microbial processes were investigated over a period of six weeks. Analytical grade (Sigma) sulphate salts of copper, zinc and nickel were added individually and in combinations to soil samples and incubated in different plastic pots. Samples were taken from the pots forthnightly and the rates of microbial carbon and nitrogen mineralization, microbial biomass carbon and respiration were measured. The results showed the effect of METALs on the measured parameters were significant (P<0.05). By the 6th week postreatment, the rates of carbon accumulated were high in the copper (6.03%) and copper:zinc (5.80 %) treatments but low in the nickel and zinc (4.93% and 5.02% respectively). The rates of nitrogen mineralization were 0.41 and 0.44 % in samples treated with copper and copper: zinc compared to 0.22%-0.24% obtained at the beginning of the experiments. Soil microbial biomass carbon declined from average value of 183.7–185.6mg/g before treatment to as low as 100.8 and 124.6mg/g in samples treated with copper:zinc and copper respectively. The rate of respiration of the soil microbial populations was equally inhibited by the METALs. From an average rate of 2.51-2.56mg of C/g respiration of the soil microbes declined to 0.98, 1.08 and 1.61mg of C/g in the copper:zinc, copper and zinc treated soils by the end of the experiment. The results suggest additive or synergistic effects of the METALs.