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Groundwater quality determination regarding major anions and cations (Case study of an aquifer in the Lut Desert, Iran) Полный текст
2015
Nasrabadi, Touraj | Baghvand, Akbar | Vosoogh, Ali
Groundwater quality regarding major anions and cations in the Birjand Plain located in the largest desert in Eastern Iran was monitored in this study. Fifteen boreholes were considered as sampling stations and the parameters pH, TDS, EC and major anions and cations were measured in groundwater samples. The dominant groundwater types can be introduced as sodium-chloride and magnesium-sulphate. The majority of samples were within the not-suitable category for drinking uses. Regarding agricultural use, around 80 and 50 per cent of samples indicated a very high salinity hazard and a very high sodium alkali hazard, respectively. Spatial distribution of salinity was also monitored within the study area. If the study area was considered to be a semicircle, the centre appeared to be the least polluted area, while towards the peripheral surroundings, an increasing behaviour was observed. Intrusion of salt water from eastern and western parts of the study area caused severe groundwater degradation. The relatively better quality of groundwater in southern areas may be attributed to a chain of mountains located along south of the study area. The prevention of uncontrolled groundwater withdrawal must be regarded to cease the salinization trend and to prepare the required infrastructure for implementing the artificial recharge projects.
Показать больше [+] Меньше [-]Spectrophotometer-based student education program on health hazard assessment due to Cr(VI) and Pb contamination in surface and groundwaters of Hyderabad City, India Полный текст
2015
Das Sharma, Mala | Juyal, Archana | Karuna, Mantha | Das Sharma, Subrata
A student-centric research education program with the active participation of undergraduate students is initiated. The aim is to imbibe ―responsible citizenship behavior‖ in them so that each member becomes conscious and well trained to take up environmental-related issues and challenges for long-term sustainability of the ecosystem. In this work, we report spectrophotometer-based estimation of hexavalent chromium (57-268 gL-1) and lead (34–158 gL-1) concentrations in different surface waters and groundwater samples in and around the city of Hyderabad, India. Our results indicate that the studied surface water bodies and aquifers are contaminated to variable degrees and pose a serious threat to the ecosystem. In view of low geochemical baseline values for chromium and lead, the origin of heavy metal pollution is inferred to be anthropogenic, mainly originating from industrial effluents. The toxicological data are integrated with health data for risk assessment and impending health hazard. Finally, the novelty of this student-centric research program is highlighted.
Показать больше [+] Меньше [-]Remote sensing technology for mapping and monitoring vegetation cover (Case study: Semirom-Isfahan, Iran) Полный текст
2015
Jabbari, Somayyeh | Khajedin, Seyed Jamaledin | Jafari, Reza | Soltani, Saeed
To determine the suitable indices for vegetation cover and production assessment based on the remote sensing data, simultaneous digital data with field data belonging to the spring rangeland of the Semirom-Isfahan province were analyzed. During two years of monitoring the annual, grass, forb, and shrub vegetation cover and the total production data from 86 were collected. The Global Positioning System (GPS) was used to measure the coordinates of plots and transects. Geometric correction and histogram equalization were applied in image processing, and image digital numbers were converted to reflectance numbers. In the next stage, all vegetation indices were calculated from the Advanced Wide Field Sensor (AWiFS) image data and compared with the vegetation cover estimates, at monitoring points, made during field assessments. A linear regression model was used to select suitable vegetation indices. The results showed that there were significant relationships between the satellite data and the vegetative characteristics. Among the indices, the Normalized Difference Vegetation Index (NDVI) consistently showed significant relationships with the vegetation cover. The estimation of the vegetation cover with the NDVI vegetation index was more accurately predicted within rangeland systems. Using the produced model from the NDVI index vegetation crown cover, percentage maps were produced in three class percentages for each image. Generally introduced indices provided accurate quantitative estimation of the parameters. Therefore, it was possible to estimate cover and production as important factors for range monitoring using the AWiFS data. The Remote sensing data and the Geographic Information System are the most effective tools in natural resource management.
Показать больше [+] Меньше [-]Studies on removal of Zinc and Chromium from aqueous solutions using water Hyacinth Полный текст
2015
Swarnalatha, K. | Radhakrishnan, Bindhu
Phytoremediation is an eco-friendly method for removal of pollutants, which can be relied upon as a sustainable technology, if implemented under optimum conditions of plant growth. The effectiveness of water hyacinth, a topical weed, for the removal of Zinc (Zn) and Chromium (Cr) ions from aqueous solutions has been presented in this article. The potential of this plant in removing metals by phytoremediation was explored under various environmental factors such as pH, salinity, metal concentrations, available nutrients, and so on. The efficiency of metal removal was observed by varying the different parameters. It was found that the maximum removal of metals occurred at a neutral pH, low amount of salinity, lower metal ion concentrations, and lack of nutrients. The stress induced in a plant by metal absorption was visible from the health and growth pattern of the plants. The stress on water hyacinth due to metals was also assessed, by observing the changes in its chlorophyll and protein content.
Показать больше [+] Меньше [-]Isolation and molecular characterization of bacteria to heavy metals isolated from soil samples in Bokaro Coal Mines, India Полный текст
2015
Gandhi, Vikram | Priya, Anshu | Priya, Suman | Daiya, Vivek | Kesari, Jitendra | Prakash, Krishna | Kumar Jha, Amrit | Kumar, Kundan | Kumar, Nitish
In recent years, environmental pollution by coal mining is a long-established human activity affecting all levels of life with various environmental impacts by generating heavy metals. The presence of heavy metals even in trace amount is toxic and detrimental to all living organisms. The coal mine area in Bokaro is one of the “Toxic Hotspot” in India. Bacteria have evolved uptake and efflux mechanisms to adapt in heavy metals contaminated environments and thus represent a potential source for bioremediation processes. In the present study, we isolated and characterized eight heavy metal resistant bacteria (NK-1 to 8) from soil sample in Bokaro coal mines, India. Isolates were selected based on high level of heavy metal resistance and its biochemical characterization. The following bacteria were identified based on 16S rRNA gene sequencing Enterobacter ludwigii (KM029957; NK-1), Klebsiella pneumonia (KM029958; NK-2), Enterobacter ludwigii (KM029959; NK-3), Enterobacter ludwigii (KM029960; NK-4), Klebsiella oxytoca (KM029961; NK-5), Enterobacter cloacae (KM029962; NK-6), Acinetobacter gyllenbergii (KM029963; NK-7), Enterobacter cloacae (KM029964; NK-8). A high degree of metal resistance associated with multiple antibiotic resistances was also detected in the selected isolate which was confirmed by the presence of plasmid. These isolates can further be used for bioremediation of heavy metals from contaminated site.
Показать больше [+] Меньше [-]Effect of a thermal power plant waste fly ash on leguminous and non-leguminous leafy vegetables in extracting maximum benefits from P and K fertilization Полный текст
2015
Inam, Akhtar | Sahay, Seema
Although the Indian population is largely vegetarian, not much attention has been given to the cultivation of vegetables, as compared to other crops like cereals, pulses and oil seeds. Therefore, the present study was conducted on two leafy vegetables, spinach (Spanacia oleracea L.) and methi (Trigonella foenum graecum L.) commonly grown in Aligarh, as the two popular vegetables of Indian diet. The study was conducted for two successive years and during the first year, phosphorus and fly ash interactions with a uniform dose of nitrogen and potassium on both vegetables was observed. During the second year, while keeping nitrogen and phosphorus uniform, potassium and fly ash combinations were studied again with both vegetables, to determine the optimum dose of inorganic fertilizers and fly ash combination. It was observed that fly ash applied at the rate of 15 t ha-1 along with N40P15K20, proved optimum for spinach while in the case of methi, N20P30K40 + FA10 was sufficient. Therefore, both vegetables can safely be grown with 10 to 15 t ha-1 of fly ash and a comparatively lower quantity of NPK.
Показать больше [+] Меньше [-]Natural radioactivity in virgin and agricultural soil and its environmental implications in Sungai Petani, Kedah, Malaysia Полный текст
2015
Ahmad, Nisar | Jaafar, Mohamad | Alsaffar, Mohammed
A study on natural radioactivity in virgin and agricultural soil samples collected from Sungai Petani was conducted using high-purity germanium. The mean activity concentrations of 226Ra, 232Th, and 40K in virgin soils were 51.06±5.83, 78.44±6.42, and 125.66±7.26 Bq kg−1, respectively, while those in agricultural soils were 80.63±5.78, 116.87±7.87, and 200.66±18.24 Bq kg−1, respectively. The corresponding activity concentrations in agricultural soils were higher than those in virgin soils and those reported for other countries of the world. The average values of radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), outdoor annual effective doses (Eout), and indoor annual effective doses (Ein) in agricultural soils were 258.38 Ba kg−1, 0.708, 0.925, 0.162 mSv y−1, and 0.669 mSv y−1, respectively. The average values of outdoor external dose (Dout) and indoor absorbed dose (Din) rate in agricultural soils were 116.04 and 218.46 nGy h−1, respectively, which were higher than the permissible limit. Soil with Hex and Hin less than unity are suitable for use as building materials and in agriculture.
Показать больше [+] Меньше [-]Assessment and control of VOCs emitted from gas stations in Tehran, Iran Полный текст
2015
Eisaei, Hamid Reza | Ahmadi Dehrashid, Seyed Shaho | Khani, Mohammad Reza | Hashemi, Seyed Mukhtar
In this research, gasoline vapours including Benzene, Toluene, Xylene (BTX) and Total Volatile Organic Compounds (TVOCs) emitted from vent pipes of underground storage tanks (USTs) were measured at six gas stations in Tehran. Thereafter, gas station No. 29 was selected as a pilot station and equipped with a vapour control system. The vapours were measured during the summer of 2013 and winter of 2014 in two states, before and at the time of gasoline discharge from a petrol tanker to the UST. The results reveal that the average of BTX and TVOCs are 161.22, 200.81, 229 and 647.01 ppm, respectively, higher than the World Health Organisation (WHO) guidelines. The average of TVOCs and BTX in the situation in which the control system is inactive at the pilot station, are 259.13, 55.9, 73.03 and 96.88 ppm, respectively. After activating the control system at the pilot station, the VOCs were reduced by 0.01 ppm. Almost 99.99% control was obtained for this system and 87% of the people living around the pilot station were satisfied and no longer had any complaints about the bad odour of VOCs. It can be concluded that gasoline discharge from the petrol tanker to UST, is the main reason behind the overproduction of VOCs in Tehran's gas stations (P<0.001). So, the most important element is to reduce VOCs at Tehran's gas stations by installing a vapour control systems in all the stations and activating the systems at the time of gasoline discharge.
Показать больше [+] Меньше [-]Potential of Lemna minor in Ni and Cr removal from aqueous solution Полный текст
2015
Goswami, Chandrima | Majumder, Arunabha
Duckweeds are of special interest, as they are naturally growing weeds that have the capacity to tolerate and remove toxic pollutants, including heavy metals from the environment. Studies have revealed that duckweed (Lemna minor) can tolerate and remove heavy metals from aqueous solutions. In the present study, the efficiency of L. minor in the removal of Ni and Cr individually from aqueous solutions was investigated at concentrations of 3.05, 3.98 and 4.9 mg/L for Ni and 1.91, 2.98, and 4.2 mg/L for Cr. Experiments were run for 22 days, after which the metal content in the plant was estimated by atomic absorption spectrophotometer (AAS). The duckweed showed higher percentage of Ni removal than Cr. Specific Growth Rate (SGR) was found to be reduced at high concentrations of both Ni and Cr. Statistical analysis suggested that the growth of the plant was affected by the toxic effect of both Ni and Cr. Bioaccumulation of Ni was higher than Cr in L. minor. The mechanism of removal of both Ni and Cr followed second order kinetics. It is suggested that these duckweeds can remove Ni and Cr from aqueous solution and can also accumulate the same in considerable concentrations, at low initial metal concentrations.
Показать больше [+] Меньше [-]Environmental policy and management of freshwater resources in the Haraz-Ghareh Su Basin in comparison to other Caspian sub basins Полный текст
2015
Hedayati Aghmashhadi, Amir | Jafari, Hamidreza | Mehrdadi, Naser | Fahmi, Hedayat | Farshchi, Parvin
Haraz-Ghareh Su is one of the seven sub-basins of the Caspian basin, located on the southern shores of the Caspian Sea, and as such, is in danger of water crisis due to absence of proper systematic policy and strategy. In this study, the pressure factors on the Haraz-Ghareh Su water resources were identified using DPSIR model. Then, the pressure parameters on the freshwater resources in the Caspian Basin were scored and prioritized into two categories: human and non-human criteria and eight sub-criteria with the help of questionnaires (the opinion of 36 specialists in environmental planning and management, as well as the use of FANP). Thereafter, the data layers were processed with the help of IDRISI software, and eventually, the data were overlaid in the ArcGIS and the final plan was made. The findings of the study shows that, among 8 effective sub-criteria on the environmental planning and management of the freshwater resources in the Haraz-Ghareh Su Basin, agricultural water consumption with 0.243 score points and dam-making with 0.039 score points are considered most and least important sub-criteria, respectively. Consequently, after the compilation and scoring of sub-basins of the Caspian basin, it appears that the sub-basin of Haraz-ghare Su with 0.158627 points had the worst situation in terms of the planning and management of freshwater resources in the Caspian basin. In order to decrease the pressure on the freshwater resources in the Haraz-Ghareh Su Basin, the formulation of long-term policy and strategy in this basin seems to be essential.
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