A study on physico-chemicals parameters, environmental pollutants, bacterial and Macrobentos distribution at the surface waters, undergrand waters and wastewater of Mangol Dam basin (Mazandaran province)

Abstract

At the present study, the water quality parameters monthly, environmental pollutants (pesticides, heavy metals and surfactants) seasonally, macrobenthos and bacteria (monthly) were done 2009 t0 2010 that located in Mangol Dam with longitude and latitude 52° 22' 49" N and 43° 15' 43" E, respectively. All water samples were collected from under-groundwater, surface water and wastewater in 12 stations and the results are as follow: The mean concentrations of DO, BOD5, COD, HCO3-, CO32-, TA, Ca2+, Mg2+, TH, TSS, TDS, Cl-, PO43-, NH4+, NO2- and NO3- were determined about 11.86±0.49, 5.95±0.11, 4.96±0.59, 28.1±6.1, 14.34±1.64, 36.30±2.33, 64.66±2.34, 28.84±1.52, 271.62±8.41, 0.37±0.03, 0.45±0.02, 28.02±1.96, 0.06±0.01, 0.010±0.001, 0.01±0.001 and 0.96±0.03 mg/l, respectively and also temperature, pH and EC were 12.7±0.61°C, 8.00±0.02 unit, 0.57±0.02 ms/cm in all samples. The surface water quality of Haraz River and its tributaries were suitable for usual applications such as aquatic matters, but based on BOD5 need to more attention for human usages. The water quality index (WQI) of surface water was classified in group II at all stations that shows serious water quality changes due to domestic and agriculture sewage. The groundwater was affected by different matters that caused change of water quality parameters. The wastewater was classified from good to moderate based on BOD5. The quality of wastewater was declined at down-stream with decreasing DO and pH and increasing BOD5 pollutants. The mean concentrations of aldrin and endrin were about 0.66 ± 0.59 and 0.71 ± 1.07 µg/l, respectively. The maximum seasonal concentration of organochlorin pesticides (OCPs) were detected in fall, winter and spring for endosulfan sulfate, γ-BHC, heptachlor, endrin aldehyde compounds about 2.85, 0.34, 0.14 and 0.14µg/l, respectively. The maximum seasonal percentage range of OCPs in fall, winter and spring for endosulfan sulfate, DDD and β-BHC were 42, 25 and 25 %, respectively. The maximum seasonal concentrations during fall, winter and spring were detected in Sorkhroud and Polechelave stations for only Fe about 1.48, 3.3 and 8.22 µg/l, respectively. Also for Hg in spring was determined about 17.2 mg/l. The mean concentration of Zn, Fe and Hg in water sampled were 0.23 ± 1.01 and 1.21 ± 2.00 µg/l, respectively and 4.65± 6.38 mg/l. The maximum concentration of linear alkyl benzene sulfonate (LAS) in summer was 971µg/l. The mean concentration of surfactant during fall, winter, spring and summer was 418.62 ± 52.16 µg/l. The maximum seasonal percentage ranges of surfactant during fall, winter, spring and summer in all stations of sampling were 76, 76, 100 and 100 %, respectively. Tottaly 15 families of macrobenthos were identified in Haraz River. The maximum mean of abundance and biomass in Sorkhroud and Nour-roud stations were 1177±256 ind/m2 and 3609 ± 935mg/m2, respectively. During Seasons, the maximum mean abundance and biomass were detected in fall and winter with 1185±444 ind/m2 and 3891±849 mg/m2, respectively. Water quality were classified by Hilsenhoff Biotic Index such as Sorkhrood station as "Very Poor", Isar town station as "Fairly Poor" and Karesang and Nor-roud stations as "good" qualification. The maximum of total coli forms and fecal coli forms in surface water were observed in Sorkhrood about 4.9 and 2.3CFU/100ml, respectively. The maximum of total coli forms and fecal coli forms in groundwater were observed in Halomsar and Absak stations about 4 and 1.7CFU/100ml, respectively. Maximum of total coli forms and fecal coli forms in wastewater were observed in Nor-roud station about 3.1 and 1.6CFU/100ml, respectively. The Ovary of nematode in wastewater were observed in Nor-roud and Isar Town stations about 30 through 124, respectively.