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91.
Environmental Science and Pollution Research - The primary objective of this research is to ascertain the relationship between corporate social responsibility, environmental investments and...  相似文献   
92.
The ground and municipal water supply samples of Karachi city were analyzed for their fluoride contents. The fluoride contents in water samples collected from the subsurface and river sources were found below the WHO recommended value for the general health of the people. However, in some industrial areas the groundwater sample showed higher level of fluoride concentration. Continuous monitoring of water resources and cautious fluoridation is suggested to maintain proper status of fluoride concentration in the drinking water.  相似文献   
93.
Concentrations in surface waters (including particulate phase) of the River Chenab ranged from 27-1100 ng L(-1) and 25-1200 ng L(-1) for OCPs and 7.7-110 ng L(-1) and 13-99 ng L(-1) for PCBs during summer and winter, respectively from 2007-2009. DDTs exhibited the highest concentration, followed by HCHs > chlordane > ∑(24)PCBs > ∑other OCPs. Different indicative ratios for organochlorines suggest that current use, long range transport and also past application of these chemicals contribute to the total burden. Statistical analysis highlighted agricultural and industrial activities and municipal waste disposal as main sources of OCPs and PCBs in the riverine ecosystem of the River Chenab. Risk Quotients (RQ(CCCs)) > 10 for DDTs and PCBs levels in collected water samples from the River Chenab suggest that risk from DDTs and PCBs is moderate to severe and fluxes calculated for OCPs and PCBs from the River Chenab to the Indus River were 7.5 tons per year and 1.0 tons per year, respectively.  相似文献   
94.
Wastewater and soil samples were collected from the industrial area of Ghaziabad City, India from January 2005 to December 2007 and were analyzed for the presence of heavy metals by atomic absorption spectrophotometry. Test samples revealed high levels of Fe, Cr, Cu, Ni, Zn, and Cd as 967.03, 34.63, 27.97, 19.7, 16.70, and 3.20 mg/L of wastewater, respectively. The concentrations of inorganic minerals were higher in the soil samples irrigated with wastewater. Total coliforms were found to be maximum (1,133 × 104 most probable number per 100 mL) during spring and summer followed by winter and postmonsoon in the wastewater samples. The microbial count in soil as well as in wastewater decreases as the metal concentration increases. The concentration 200 μg/mL of nickel and cadmium inhibits majority of the population, while, at some points, it inhibits 100% of the population. The exponential decay model for microbial count at the increasing metal concentrations indicate that asymbiotic N2 fixers were best fitted to the model. In all the seasons, the order of decline in terms of exponential decay of the population of different microbial groups in soil was asymbiotic N2 fixers > actinomycetes > fungi > aerobic heterotrophic bacteria. The different microbial groups that have different values of slope in different seasons indicate that the resistant population of microorganisms was variable with seasons.  相似文献   
95.
The work describes the physicochemical analysis of the water samples collected from Lahore Canal to evaluate pollution load at different points of the canal. Different physical and chemical pollutants such as temperature, pH, electrical conductivity, total dissolved and suspended solids, turbidity, chlorides, sulphates, nitrates, oils and grease, dissolved oxygen, chemical oxygen demand and biological oxygen demand (BOD) were analysed. The data was analysed through analysis of variance, which showed that the p values for dissolved oxygen (DO), chemical oxygen demand (COD), BOD, electrical conductivity, total dissolved solid (TDS), total suspended solid (TSS), turbidity, oil and grease, sulphates, and nitrates are <0.05, while p value of temperature, pH, and chlorides are 1.000, 0.984, and 0.070, respectively, which are >0.05. Further regression analysis revealed that the simple line regression modal is fit for turbidity and TSS, electrical conductivity and TDS, COD and DO, BOD and DO, and BOD and COD. The studies reveal that Lahore Canal is receiving a considerable amount of physical and chemical pollutants at different points.  相似文献   
96.
Controlled release (CR) formulations of carbofuran and imidacloprid were prepared employing polyvinyl chloride and carboxymethyl cellulose (CMC) and their bioefficacy was evaluated against the aphid, Aphis gossypii and leafhopper, Amrasca biguttula biguttula Ishida on potato crop. The CR formulations of carbofuran and imidacloprid provided better or equal control of the pests than commercial formulations. CMC-based formulation provided a superior control of both the pests. The Imida-CMC, which showed the lowest population of leaf hopper (10.50 leafhopper/100 cl), provided significantly superior control among all treatments after 35 days after germination (DAG). The residue of carbofuran and imidacloprid in potato tuber and soils were not detectable at the time of harvesting in any one of the formulations.  相似文献   
97.
Feathers of two colonial water-birds species (Bubulcus ibis, Egretta garzetta) from four heronries in the Punjab province, Pakistan were analysed for 28 Polybrominated Diphenyl Ethers (PBDEs) congeners. Median concentrations of ∑PBDEs were 2.41 and 1.91 ng/g in little and cattle egrets. PBDE-47, -100, -138, -153 were abundant and detected in >70% of feather samples in both species. Species-specific differences based on dietary preferences indicated higher concentration of PBDE-47, -66, -75, -100, -153, -154, and -183 in fish eating little egret. BDE-47 and -100 were more frequent in little egrets and BDE-99 was more dominant in cattle egret which feed on terrestrial habitat. Higher ∑hexa- and hepta-BDEs congeners showed larger concentrations in feathers from heronries close to water bodies which receive urban and industrial effluents whereas lower-brominated congeners (BDE-47-BDE-100) dominated in rural/agricultural regions. Hazard quotients (HQs) indicated that measured ∑PBDEs pose no risk to egret population.  相似文献   
98.
Concentration of ten metals (Cd, Cr, Co, Cu, Fe, Li, Mn, Ni, Pb and Zn) were analyzed in the egg contents, prey and soil samples of little egret (Egretta garzetta) and cattle egret (Bubulcus ibis) from two Headworks to determine habitat and species-specific differences; to assess the importance of prey and habitat contamination as an exposure source for heavy metals. Concentration of Cu, Mn, Cr and Pb in egg contents, Fe, Co, Cu, Mn, Zn in prey and Fe, Co, Cu, Ni, Li in surface soils were significantly different (P < 0.05). Mean metal concentrations of Cr, Pb and Cd were relatively higher in little egret whereas Cu and Mn were higher in the egg contents of cattle egret. The mean concentrations of Cu, Mn and Zn were higher in prey samples of cattle egrets and Cr, Cd and Pb in prey samples of little egrets. In soil samples collected from little egret heronries metal concentrations were higher except Cu and Ni. Correlation Analysis and Hierarchical Agglomerative Cluster Analysis (HACA) identified relatively similar associations of metals and their source identification. Metals such as Fe, Cu, Mn, and Li were related with geochemical origin from parent rock material as well as anthropogenic input whereas Cr, Cd, Pb, Ni, Co and Zn were associated mostly with anthropogenic activities. The study suggested that eggs are useful bio-monitor of local heavy metal contamination.  相似文献   
99.
Abstract

Bioavailability of fluridone, l‐methyl‐3‐phenyl‐5‐[3‐(trifluoromethyl) phenyl]‐4(1H)‐pyridinone, as affected by soil temperature, soil moisture regime, and duration of incubation was investigated in three soil types by grain sorghum (Sorghum bicolor [L.] Moench cv. Abu Sabien) chlorophyll bioassay. Initial loss of fluridone was rapid and dissipation followed first‐order kinetics under most of the incubation treatments investigated. Soil moisture, in general, had a greater impact than soil temperature on dissipation of fluridone. The herbicide dissipated faster at the fluctuating room temperature (18–24°C) than at the constant 10°C in Sonning sandy clay loam (O.M. = 1.2%) and Erl Wood sandy loam (O.M. = 2.5%) but not in Shropshire loamy peat (O.M. = 33%). In the two mineral soils, bioassay‐detectable residues from an initial rate of 1.00 μg/g were least (0.00 ‐ 0.10 μg/g) at 1/2 field capacity (FC) and greatest (0.16 ‐ 0.37 μg/g) at 1/4 FC, 400 days after treatment. At 10°C, the DT50 values (days) at 1/4 FC and 1/2 FC were, respectively, 147 ± 16 and 69 ± 6 for Erl Wood soil, and 257 ± 28 and 51 ± 12 for Sonning soil. In Shropshire soil, concentrations of bioavailable fluridone were least at each bioassay date when soil moisture was maintained at FC, at both temperatures of incubation. At 10°C, herbicide concentrations in the organic soil from an initial rate of 10.00 μg/g were 0.95 and 4.69 μg/g, respectively, at FC and 1/4 FC.  相似文献   
100.
Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-14448-7  相似文献   
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