Roy S.,Gurucharan College |
Gupta A.,Assam University
Pollution Research | Year: 2011
River Barak and its tributaries are major sources of usable water in the densely populated Barak valley of Assam, India. This paper makes an assessment of the physical, chemical and biological characteristics of River Barak and its tributaries during 2002 to 2006 at 12 sites. Habitat scores (based on RBP III) at all the sampling sites mostly ranged between the 'suboptimal' and 'marginal' categories, thereby indicating their neither pristine nor heavily impacted nature. Among the twelve stations of the Barak River system, River Chiri had the highest value of pH, total alkalinity and dissolved oxygen. At the same time, it also had the lowest value of water temperature, electrical conductivity, total dissolved solids and BOD, thereby revealing that this site, located in the upstream area of the Barak Catchment in Cachar district, was the least disturbed. As the river flowed further downstream to enter Silchar, the largest urban center in this area, there was an immediate decline in pH, total alkalinity and DO and a concomitant increase in water temperature, TDS and BOD. BOD (5 days) remained below the acceptable limit in R. Kushiara. Possible correlations were made between the habitat score and water quality parameters. Habitat degradation in River Barak and its tributaries might have occurred due to anthropogenic activities like agriculture, disposal of sewage and other waste, mass bathing and washing of clothes in the river and its catchment. © EM International.
Das Astapati A.,Gurucharan College |
Das A.K.,Assam University
Journal of Environmental Biology | Year: 2012
Imperata grassland at Dorgakona, Barak valley, North Eastern India was analyzed for species composition and diversity pattern in relation to traditional management practices. 19 families were in the burnt and unburnt plots of the study site with Poaceae as the most dominant one. 29 species occurred in the burnt plot and 28 in the unburnt plot. Most of the species were common in both the plots. The pattern of frequency diagrams indicated that the vegetation was homogeneous. Imperata cylindrica, a rhizomatous grass was the dominant species based on density (318.75 and 304.18 nos. m-2), basal cover (158.22 and 148.34 cm2 m-2) and Importance value index (IVI) (132.64 and 138.74) for the burnt and unburnt plots respectively. Borreria pusilla was the co-dominant species constituting Imperata-Borreria assemblage of the studied grassland. It was observed that B. pusilla (162.25 nos. m-2 and 50.37 nos. m-2),/. cylindrica (318.75 nos. m-2 and 304.18 nos. m-2) and Setaria glauca (24.70 nos. m-2 and 16.46 nos. m-2) were benefited from burning as shown by the values sequentially placed for burnt and unburnt plots. Certain grasses like Chrysopogon aciculatus and Sacciolepis indica were restricted to burnt plot while Oxalis corniculata showed its presence to unburnt plot. Grasses dominated the grassland as revealed by their contribution to the mean percentage cover of 72% in burnt plot and 76% in unburnt plot. The dominance-diversity curves in the study site approaches a log normal series distribution suggesting that the resources are shared by the constituent species. Seasonal pattern in diversity index suggested definite influence of climatic seasonality on species diversity; rainy season was conducive for maximum diversity (1.40 and 1.38 in the burnt and unburnt plots, respectively). Dominance increased with concentration of fewer species (0.0021 in burnt plot and 0.0055 in unburntplot) in summer and behaves inversely to index of diversity. This study showed that the traditional management practices benefits the farmers as it promote grassland regeneration with I. cylindrica as the dominant grass. © Triveni Enterprises.
Mohanta S.,Assam University |
Sharma G.D.,Assam University |
Deb B.,Gurucharan College
Journal of Pure and Applied Microbiology | Year: 2012
Plant constitute vast and diverse niche for endophytic microbes. Endophytic bacteria reside within plants without causing disease symptoms. During the association the invading bacteria benefit the acquired host with a marked increase in plant growth, vigor and yield. The diversity of endophytic microbes to a large extent remains unexplored. In this study fresh roots of Cymbopogon species were used for the isolation of endophytic diazotrophic bacteria using standard methods. Cymbopogon species are widely used all over the India as an aromatic and medicinal plant. The most frequently endophytic diazotrophs isolated from Cymbopogon species are Klebsiella pneumoniae, Bacillus pumilus, Pseudomonas fluorescence and Burkholderia cenocepacia. Determining genetic relationship between the species or genera is very important for genetic improvement and phylogenetic studies. In silico study was conducted to understand the major evolutionary relationships among the endophytic bacteria of Cymbopogon species using nucleotide sequence of 16s ribosomal RNA with other bacteria obtained from GenBank.
Sunar K.,Gurucharan College |
Bodo B.,Nanoscience Research Laboratory |
Kalita P.K.,Nanoscience Research Laboratory
AIP Conference Proceedings | Year: 2010
In the present work thin films of Cd0.7Zn0.3S ternary compound have been deposited onto glass substrates by chemical bath deposition method at 300oK (room temperature). The structural morphology of the synthesized compound was studied using XRD, TEM as well as SEM techniques. XRD shows the prepared CdZnS are polycrystalline having wurtzite type structure. TEM and images exhibit a uniform distribution of hexagonal shaped particles. EDS confirms the formation of ternary semiconductor from the compositional analysis. The particle size measured from TEM & SEM shows the agglomeration of nanoparticles with a larger particle 45-65 nm. UV-VIS measurement shows prominent absorption peak at 474nm along with 734nm The Photoluminescence exhibit the band edge emission at 490 nm along with other blue-green emissions © 2010 American Institute of Physics.
Goswmai S.,Gurucharan College |
Das K.K.,Gauhati University
Jornal de Pediatria | Year: 2015
Objective To evaluate socio-economic and demographic determinants of anemia among Indian children aged 6-59 months. Methods Statistical analysis was performed on the cross-sectional weighted sample of 40,885 children from 2005 to 2006 National Family Health Survey by using multinomial logistic regression to assess the significance of some risk factors in different degrees of child anemia. Anemia was diagnosed by World Health Organization (WHO) cut-off points on hemoglobin level. Pearson's chi-squared test was applied to justify the associations of anemia with different categories of the study population. Results The prevalence of anemia was 69.5%; 26.2% mild, 40.4% moderate, and 2.9% severe anemia. Overall prevalence rate, along with mild and moderate cases, showed an increasing trend up to 2 years of age and then decreased. Rural children had a higher prevalence rate. Of 28 Indian states in the study, 10 states showed very high prevalence, the highest being Bihar (77.9%). Higher birth order, high index of poverty, low level of maternal education, mother's anemia, non-intake of iron supplements during pregnancy, and vegetarian mother increased the risks of all types of anemia among children (p < 0.05). Christian population was at lower risk; and Scheduled Caste, Scheduled Tribe, and Other Backward Class categories were at higher risk of anemia. Conclusion The results suggest a need for proper planning and implementation of preventive measures to combat child anemia. Economically under-privileged groups, maternal nutrition and education, and birth control measures should be priorities in the programs. © 2015 Sociedade Brasileira de Pediatria.