An experimental investigation to characterise soil macroporosity under different land use and land covers of northeast India

Saturated macropore flow is the dominant hydrological process in tropical and subtropical hilly watersheds of northeast India. The process of infiltration into saturated macroporous soils is primarily controlled by size, network, density, connectivity, saturation of surrounding soil matrix, and depthwise distribution of macropores. To understand the effects of local land use, land cover and management practices on soil macroporosity, colour dye infiltration experiments were conducted with ten soil columns (25 × 25 × 50 cm) collected from different watersheds of the region under similar soil and agro-climatic zones. The sampling sites included two undisturbed forested hillslopes, two conventionally cultivated paddy fields, two forest lands abandoned after Jhum cultivation, and two paddy fields, one pineapple plot and one banana plot presently under active cultivation stage of the Jhum cycle. Digital image analyses of the obtained dye patterns showed that the infiltration patterns differed significantly for different sites with varying land use, land cover, and cultivation practices. Undisturbed forest soils showed high degree of soil macroporosity throughout the soil profile, paddy fields revealed sealing of macropores at the topsoil due to hard pan formation, and Jhum cultivated plots showed disconnected subsoil macropores. The important parameters related to soil macropores such as maximum and average size of macropores, number of active macropores, and depthwise distribution of macropores were estimated to characterise the soil macroporosity for the sites. These experimentally derived quantitative data of soil macroporosity can have wide range of applications in the region such as water quality monitoring and groundwater pollution assessment due to preferential leaching of solutes and pesticides, study of soil structural properties and infiltration behaviour of soils, investigation of flash floods in rivers, and hydrological modelling of the watersheds.     

Morphometry and Morphostructural Studies of the Parts of Gola River and Kalsa River Basins,Chanphi-Okhalkanda Region,Kumaun Lesser Himalaya,India

Geotectonics - Study of morphometric parameters such as stream length (Lu) and stream length ratios (Rl), bifurcation ratio (Rb), drainage density (D), form factor (Rf), circularity ratio (Rc),...     

Biofilm Formation by Microorganisms Isolated from Paper Mill Effluent and its Public Health Implications

The microbiological assessment of biofilm formation from paper mill effluent discharged through a pipeline revealed a maximum microbial count for Pseudomonas (5·10⁶ cfu/mL) followed by Staphylococcus (4·10⁶ cfu/mL), Bacillus (8.2·10⁵ cfu/mL), Burkholderia (7.2·10⁵ cfu/mL), Enterobacter (5.3·10⁴ cfu/mL), Acinetobacter (4.1·10³ cfu/mL), Alcaligenes (1.2·10² cfu/mL) and Klebsiella (0.8·10² cfu/mL) species. Among these species, the maximum biofilm formation was observed after 24 h of incubation by Pseudomonas sp. using a crystal violet (CV) assay. This isolate was later identified by 16S rRNA amplification to be Pseudomonas aeruginosa PME1. Extracellular polymeric substances (EPS) of P. aeruginosa PME1 in the biofilm showed a reduction in total carbohydrate content (42%) with increased protein (9.0%), hexosamine (3.0%) and uronic acid (1.7%) content as compared to its planktonic form. Antimicrobial susceptibility testing revealed that P. aeruginosa PME1 biofilms were 17, 24, 27, 30, and 32 times more resistant to cefotaxime, imipenem, ceftazidime, tazobactam and piperacillin, respectively, than their free flowing counterparts.     

A hierarchical model for estimating methane emission from wetlands using MODIS data and ARIMA modeling

A three-step hierarchical Semi Automated Empirical Methane Emission Model (SEMEM) has been used to estimate methane emission from wetlands and waterlogged areas in India using Moderate Resolution Imagine Spectroradiometer (MODIS) sensor data onboard Terra satellite. Wetland Surface Temperature (WST), methane emission fluxes and wetland extent have been incorporated as parameters in order to model the methane emission. Analysis of monthly MODIS data covering the whole of India from November 2004 to April 2006 was carried out and monthly methane emissions have been estimated. Interpolation techniques were adopted to fill the data gaps due to cloudy conditions during the monsoon period. AutoRegressive Integrated Moving Average (ARIMA) model has been fitted to estimate the emitted methane for the months of May 2006 to August 2006 using SPSS software.     

An integrated approach for ground water investigation in part of Fatehpur Sikri of district agra-a case study

The Fatehpur Sikri area infringing the western UP, Rajasthan border was investigated for its water supply crisis in respect of poor quality and quantity as well. The study has indicated presence of two parallel quartz reefs running in NE-SW direction. Geohydrological and photogeological studies have revealed the possibility of subsurface extension of quartz reefs. However, this weathered area along reefs is promising water bearing zone. Paleo channels are also marked during studies and the area found suitable for ground water exploitation. A map showing various categories is also presented.     

Evaluation of ground water potential in the environs of Jhansi city,Uttar Pradesh using hydrogeomorphological assessment by satellite remote sensing technique

An attempt has been made to delineate different hydrogeomorphological units in and around the immediate environs of Jhansi city with a view to attempt a correlation between the well yields and hydrogeomorphic units using satellite remote sensing technique. In general, a positive correlation is observed between the geomorphic units and the borewell yields with overlapping yields at the margin. The pediment residual hill complex is observed to provide wells with discharges ranging from 100 gallons per hour (gph) to 5000 gph, while the wells drilled in shallow weathered, buried pediplain has yields in the range of 2000 to 10000 gph moderately weathered, buried pediplain has discharges in the range of 8000 to 12000 gph, and deeply weathered, buried pediplain has discharges in excess of 12000 gph.     

Effect of Three Synthetic Pyrethroids to a Non-target Fish,Channa striatus Wirkung von drei synthetischen Pyrethroiden auf einen Nichtziel-Organismus,den Fisch Channa striatus

Exposure of Channa striatus over 24 h to 40% and 80% of the LC_50;24h of the three pyrethroids cypermethrin, permethrin, and fenvalerate did not cause any significant changes in the levels of total protein and free amino acids in the liver and muscle tissues of the fish. After 96 h exposure, the protein amino acid levels are altered significantly.     

Kinetics,Mechanistic and Thermodynamics of Zn(II) Ion Sorption: A Modeling Approach

Biosorption potential of Cedrus deodara sawdust (CDS) in terms of sorption of Zn(II) ion across liquid phase has been evaluated in the present investigation. The surface of the CDS biomass before the sorption of Zn(II) ions seemed to be more porous, non‐crystalline and heterogeneous. The maximum uptake capacity of CDS was 97.39 mg g^?1. Sorption of Zn(II) ion on the surface of CDS sawdust was maximum at pH 5, temperature 45°C, initial concentration of Zn(II) ion 100 mg L^?1, biomass dose 1 g L^?1, contact time 150 min, and agitation rate 160 rpm. Pseudo second‐order kinetics with the highest linear regression coefficient (R² = 0.99), and lowest values of error functions, i.e., chi (χ²) and sum of square errors (SSE) against pseudo first‐order rate kinetics showed that the sorption of Zn(II) ion on the surface of CDS was mediated by chemosoprtive forces of attraction rather than physical adsorption. Mechanistically, relatively higher proportion of sorption of Zn(II) ion in early phase of contact time was profoundly explained by Bangham's equation and film diffusivity (D^f). Intraparticle or pore diffusion (D_p) of Zn(II) ion inside the pores of CDS was rate limiting step at the later stage of contact time. Furthermore, the thermodynamic study on sorption of metal ion delineated the fact that the Zn(II) sorption on the surface of CDS was spontaneous, endothermic together with increased entropy at solid liquid interface.     

Action Sites of Cypermethrin,a Synthetic Pyrethroid in the Snail Lymnaea acuminata

24 h of in vivo exposure to 40 and 80 = LC50 of the synthetic pyrethroid cypermethrin significantly reduced the acetylcholinesterase, cytochrome oxidase and lactic dehydrogenase activity in the nervous tissue of L. acuminata. Succinic dehydrogenase activity increased significantly after the same treatment. Fifteen minutes in vitro exposure to different doses of cypermethrin also significantly inhibited cytochrome oxidase and lactic dehydrogenase activity. However, acetylcholinesterase and succinic dehydrogenase activities remain unaltered. It is concluded that the cypermethrin on the one hand causes repititive discharges at the nerve terminal and on the other hand blocks the electron transport chain.