Mine waste water at South Kaliapani usually contains toxic levels of hexavalent Cr(VI). The present in situ study was conducted at South Kaliapani chromite mine area in Orissa state, India, to assess the phytoremediation ability
of three plants, namely, rice (Oryza sativa L.), paragrass (Brachiaria mutica), and an aquatic weed (Eichhornia crassipes), in attenuating Cr(VI) from mine waste water and to correlate the bio-concentration factors (BCF) of Cr. Water hyacinth
(E. crassipes) showed 24% to 54% reduction whereas paragrass (B. mutica) was able to reduce 18% to 33% of Cr(VI) from mine water. This reduction was studied over a period of 100 days of plant growth.
The reduction was observed through a passage of a sum total of 2,000 sq. ft. cultivated plots and ponds separately. Reduction
in Cr(VI) content in mine water varies with plant age as well as with the distance of passage. Cr accumulation and BCF values
increased with high soil Cr levels as well as the age of plants. High BCF and transportation index (Ti) values, i.e., 10,924
and 32.09, respectively, were noted for water hyacinth. The Ti values indicated that the root-to-shoot translocation of Cr
was very high after 100 days of growth. The total accumulation rate was maximum (8.29 mg Cr kg dry biomass − 1 day − 1) in paragrass. The BCF values for roots were noted to be higher than those of leaves, stems, and grains of the 125-day-old
plants. Hence, paragrass and water hyacinth may be used as tools of phytoremediation to combat the problem of in situ Cr contamination. 相似文献
The present investigation reports the assessment of hydrochemical/geochemical processes controlling the concentration of fluoride
in groundwater of a village in India (Boden block, Orissa). Boden block is one of the severely affected fluoride-contaminated
areas in the state of Orissa (India). The sampling and subsequent analysis of water samples of the study area was carried
out following standard prescribed methods. The results of the analysis indicate that 36.60% groundwater F− concentration exceeds the limit prescribed by the World Health Organization for drinking water. The rock interaction with
groundwater containing high concentration of HCO3− and Na+ at a higher pH value of the medium could be one of the important reasons for the release of F− from the aquatic matrix into groundwater. Geochemical classification of groundwater based on Chadha rectangular diagram shows
that most of the groundwater samples having fluoride concentration more than 1.5 mg L−1 belongs to the Na-K-HCO3 type. The saturation index values evaluated for the groundwater of the study area indicated that it is oversaturated with
respect to calcite, whereas the same is undersaturated with respect to fluorite content. The deficiency of calcium ion concentration
in the groundwater from calcite precipitation favors fluorite dissolution leading to excess of fluoride concentration. The
risk index was calculated as a function of fluoride level in drinking water and morbidity of fluorosis categorizes high risk
for villages of Amera and Karlakote panchayat of Boden block. 相似文献
The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent. 相似文献
Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest
anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment
and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation.
In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between
different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses
of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between
the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants
for pollution monitoring of these metals. 相似文献
The local belief systems are crucial for climate change adaptation. Even climate experts are unanimous about the fundamental association between local beliefs and climate change adaptation strategies. However, the local perspective is missing from the significant policy dialog platforms. The local beliefs can potentially serve as both objective and psychological refuge for local societies during climate-related emergencies. Similarly, only limited studies have acknowledged the significance of local food choices, providing a model for global responses to climate change. The objective of the study is (i) to explore the local community’s insights and awareness of climate change and (ii) to assess the impact on local food choices affecting their food security in the face of climate change in the Western Himalayan Region, India. The study is based on 210 in-depth household interviews and surveys in 10 villages of Uttarakhand, India. The exploratory factor and thematic analysis results highlight the significance of local perception of climatic variabilities, food choices, and beliefs in climate change adaptation policies. Hence, the current study’s outcomes emphasize on the integration and promotion of both scientific methods and local knowledge for inclusive climate change adaptation and food security policies in the Himalayan Region. 相似文献
A new series of halogenated Schiff bases was synthesized by the condensation of 5-fluoro-2-hydroxy acetophenone and 3,5-dichloro-2-hydroxy acetophenone with different alkyl amines, namely propyl, pentyl, hexyl, heptyl, octyl, nonyl, dodecyl, tetradecyl, hexadecyl, and octadecyl amines, under microwave irradiation. Newly formed molecules were characterized by Infrared and nuclear magnetic resonance (1H NMR and 13C NMR) spectroscopic techniques. Further, the Schiff bases were screened for antifungal bioassay, and the results showed potential fungicidal activity against two very important plant infecting fungi, viz. Rhizoctonia solani and Sclerotium rolfsii. Among the screened compounds, 2,4-dichloro-2-[1-(propylimino)ethyl]phenol was found to be the most active compound against both R. solani (ED50 8.02 mg L?1) and S. rolfsii (ED50 21.51 mg L?1) followed by 2,4-dichloro-2-[1-(pentylimino) ethyl]phenol (ED50 13.02 and 29.57 mg L?1, respectively). The synthesized compounds were also screened for antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging technique. All the compounds showed very low to moderate activity as compared with Gallic acid. 相似文献
Every year, during the pre-monsoon period (March–May), a pronounced increase in aerosol optical depth (AOD) is observed over the eastern Arabian Sea, which is attributed to the transport of continental aerosols. This paper presents the altitude distribution of tropospheric aerosols, characteristics of elevated aerosol layers and aerosol radiative heating of the atmosphere during the pre-monsoon season over Trivandrum (8.5°N, 77°E), a station located at the southwest coast of Indian peninsula which is covered by the eastern Arabian Sea plume. Altitude profiles of aerosol backscatter coefficient (βa) and linear depolarization ratio (LDR) reveal two distinct aerosol layers persisting between 0–2 km and 2–4 km. The layer at 2–4 km, which contributes about 25% of the AOD during polluted conditions, contains significant amount of non-spherical aerosols. This layer is prominent only when the advection of dry airmass occurs from the northern parts of the Indian subcontinent and northern Arabian Sea. Role of long-range transport in the development of this aerosol layer is further confirmed using latitude–altitude cross-section of βa observed by CALIPSO. Aerosol content in the layer below 2 km is large when advection of air occurs from the north and east Arabian Sea and is significantly small when it occurs from the southwest Arabian Sea or Indian Ocean. During the highly polluted conditions, aerosols tend to increase the diurnal mean atmospheric radiative heating rate by ~0.8 K day?1 at 500 m and 0.3 K day?1 at 3 km, which are about 80% and 30% of the respective radiative heating in the aerosol-free atmosphere. 相似文献
Environmental Chemistry Letters - Cancer is one of the most fatal diseases causing deaths of millions of people worldwide. Since actual cancer treatments are rarely efficient and often toxic, there... 相似文献
The Flavivirus genus is divided into four groups: Mosquito-borne flaviviruses, Tick-borne flaviviruses, no-known vector flaviviruses, and Insect specific flaviviruses. Millions of people are affected worldwide every year due to the flaviviral infections. The 5' UTR of the RNA genome plays a critical role in the biology of flaviviruses. To explore any correlation between the topology of the 5' UTR and pathogenesis, a global scale study of the RNA secondary structure of different groups of flaviviruses has been conducted. We found that most of the pathogenic flaviviruses, irrespective of their mode of transmission, tend to form a Y shaped topology in the Stem loop A of the 5' UTR. Some of the current non-pathogenic flaviviruses were also observed to form Y shaped structure. Based on this study, it has been proposed that the flaviviruses having the Y shaped topology in their 5′ UTR regions may have the potential to become pathogenic.