Current Science

Rajesh Kumar ¹, V. N. Jha ¹, S. K. Sahoo ¹, S. Jha ², S. Kumar ², P. M. Ravi ¹, R. M. Tripathi ¹

Affiliations
1 Health Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, IN
2 Uranium Corporation of India Limited, Turamdih 832 102, IN

Abstract

Estimation of radionuclide content is essential for assessment of individual exposure in areas where groundwater is the principal source of drinking water. Elevated levels can be expected in areas known for radioactive mineral deposits and anthropogenic activities like mining and ore processing industry. The aim of this study is to determine the uranium and ²²⁶Ra in groundwater sources adjoining and away from uranium mining and ore processing industry at Turamdih, Jharkhand. The concentration of uranium in well/tubewell samples analysed nearby and away from the tailings ponds ranged from 0.1 to 8.4 μg l^-1 and ²²⁶Ra varied from 4 to 269 mBq l^-1. The wide variation of activity concentration is due to regions of uranium deposits with elevated level of radium in the earth's crust and geological faults, when compared to lower concentration profile of radium in earth crust. The ingestion of uranium and ²²⁶Ra in the adult population residing around Turamdih mining complex through drinking water sources ranged from 0.81 μSv year^-1 to 3.8 μSv year^-1 respectively. This is much lower than 100 μSv year^-1, that is recommended by WHO for ingestion from intake of a single radionuclide. The groundwater monitoring carried out over four years around Turamdih mining complex indicates that there has been no observable impact on groundwater sources due to mining and ore processing activities in this region.

Keywords

Groundwater, Ingestion Dose, ²²⁶Ra, Uranium.

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Rajesh Kumar ¹, Vayalam P. Venugopalan ¹

Affiliations
1 Biofouling and Biofilm Processes Section, Water and Steam Chemistry Division, Bhabha Atomic Research Centre, Kalpakkam 603 102, IN

Abstract

Natural aquatic biofilms (e.g. periphyton) play a major role in the degradation of conventional pollutants as well as xenobiotics that enter our aquatic systems. The remarkable ability of biofilms to degrade pollutants has been harnessed for purposes such as wastewater treatment. Recent developments in aerobic microbial granulation technology have brought about substantial improvements in biofilm-based remediation processes, offering several advantages such as high biomass retention, rapid biomass settling, high tolerance to toxicity, ability to withstand shock loading and low excess sludge production. We hypothesized that the diverse metabolic machinery and mixed microbial (bacterial, cyanobacterial and microalgal) functions of lotic biofilms could be exploited, if they can be successfully reproduced in the laboratory in the form of granular biomass. Accordingly, a method was developed for the cultivation of phototrophic aerobic microbial granules using bubble column photobioreactors. Mixed inoculum consisting of activated sludge and mixed microalgal cultures was added to column-type bubbled photobioreactors, which were operated in sequential batch mode with 24 h cycle time and 30% volumetric retention. Granulation of biomass was achieved within five weeks. The significance of the work is that it combines the advantages of both aerobic granular sludge and phototrophic biofilms. The bioreactors can be operated without addition of any external organic carbon source, as carbon fixation by the phototrophic elements can support the mixed microbial biomass in the reactor. This granular phototrophic mixed microbial biomass consortium has tremendous applications in environmental biotechnology, which was demonstrated by degrading a toxic model pollutant (phenol).

Keywords

Biofilm, Bioremediation, Granular Biomass, Microbial Aerobic Granules.

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Sachin D. Ghude ¹, C. K. Jena ¹, G. Beig ¹, Rajesh Kumar ², S. H. Kulkarni ³, D. M. Chate ¹

Affiliations
1 Indian Institute of Tropical Meteorology, Dr Homi Bhabha Road, Pune 411 008, IN
2 National Center for Atmospheric Research, Boulder Co, US
3 Centre for Development of Advance Computing, Pune 411 007,, IN

Abstract

In this study, we evaluate the potential impact of ground level ozone (O₃) on rice and wheat yield in top 10 states in India during 2005. This study is based on simulated hourly O₃ concentration from the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem), district-wise seasonal crop production datasets and accumulated daytime hourly O₃ concentration over a threshold of 40 ppbv (AOT40) indices to estimate crop yield damage resulting from ambient O₃ exposure. The response of nitrogen oxides (NO_x) and volatile organic compounds (VOC) mitigation action is evaluated based on ground level O₃ simulations with individual reduction in anthropogenic NO_x and VOC emissions over the Indian domain. The total loss of wheat and rice from top 10 producing states in India is estimated to be 2.2 million tonnes (3.3%) and 2.05 million tonnes (2.5%) respectively. Sensitivity model study reveals relatively 93% decrease in O₃-induced crop yield losses in response to anthropogenic NO_x emission mitigation. The response of VOC mitigation action results in relatively small changes of about 24% decrease in O₃-induced crop yield losses, suggesting NO_x as a key pollutant for mitigation. VOC also contribute to crop yield reduction but their effects are a distant second compared to NO_x effects.

Keywords

AOT40, Chemical Transport Model, Crop Damage, Ozone, Yield Loss.

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Manish Naja ¹, Piyush Bhardwaj ¹, Narendra Singh ¹, Phani Kumar ¹, Rajesh Kumar ², N. Ojha ¹, Ram Sagar ³, S. K. Satheesh ⁴, K. Krishna Moorthy ⁵, V. R. Kotamarthi ⁶

Affiliations
1 Aryabhatta Research Institute of Observational Sciences, Nainital 263 002, IN
2 National Center for Atmospheric Research, Boulder, Colorado, US
3 Indian Institute of Astrophysics, Bengaluru 560 034, IN
4 Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bengaluru 560 012, IN
5 Indian Space Research Organization, Head Quarters, Bengaluru 560 231, IN
6 Argonne National Laboratory, Argonne, IL, US

Abstract

An extensive field study, RAWEX-GVAX, was carried out during a 10-month (June 2011-March 2012) campaign at ARIES, Nainital and observations on a wide range of parameters like physical and optical properties of aerosols, meteorological parameters and boundary layer evolution were made. This work presents results obtained from high-frequency (four launches per day), balloon-borne observations of meteorological parameters (pressure, temperature, relative humidity, wind speed and wind direction). These observations show wind speed as high as 84 m/s near the subtropical jet. It is shown that reanalysis wind speeds are in better agreement at 250 hPa (altitude of subtropical jet) than those above or below this value (100 hPa or 500 hPa). These observations also demonstrate that AIRS-derived temperature profiles are negatively biased in the lower altitude region, whereas they are positively biased near the tropopause. WRF simulated results are able to capture variations in temperature, humidity and wind speed profile reasonable well. WRF and AIRS-derived tropopause height, tropopause pressure and tropopause temperature also show agreement with radiosonde estimates.

Keywords

Aerosols, Radiosonde, Subtropical Jet, Tropopause Folding, Vertical Profiling.

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Chhaya Verma ¹, Amar Jyoti Das ¹, Rajesh Kumar ¹

Affiliations
1 Rhizosphere Biology Laboratory, Department of Environmental Microbiology, School for Environmental Sciences, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow 226 025, IN

Abstract

One of the major problems, that the world is facing today due to rapid industrialization is environmental pollution caused by several factors, including heavy metals. Among the heavy metals, cadmium is a hazardous carcinogenic element. From contaminated soil, cadmium enters the plants through the ischolar_mains and is accumulated in the harvestable (edible) parts, and thus gains entry into the food cycle. Phytoremediation plays a beneficial role in the remediation of cadmium contamination from soil, but becomes less effective with increasing toxicity. Even hyperaccumulator plants fail to perform under these conditions. Plant growth promoting rhizobacteria (PGPR), inhabitants of the plant rhizosphere, play a supporting role and promote bioremediation of soil by accumulation or transformation of contaminants, thereby enhancing plant growth and development. This article focuses on cadmium contamination and PGPR-assisted phyto-remediation of cadmium-contaminated soils.

Keywords

Cadmium, Phytoremediation, Plant Growth Promoting Rhizobacteria, Toxicity.

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krishna Giri ¹, Gaurav Mishra ¹, R. S. C. Jayaraj ¹, Rajesh Kumar ¹

Affiliations
1 Rain Forest Research Institute, Jorhat - 785 001, IN

Abstract

North East India is one of the culturally diverse regions in the world inhabited by more than 200 tribes in eight states. Also, the region is one of the biodiversity hot spots of the world. The region is endowed with rich floral, faunal and sociocultural diversity. These tribes have originated from the ethnic groups of Tibeto-Burmese and Indo-Mongoloids¹. The tribal communities of this region live in hilly areas and depend on forest resources for their livelihood. Shifting cultivation is the major agricultural land use system in undulating hilly terrains of this region.

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Sachin D. Ghude ¹, Rajesh Kumar ², Chinmay Jena ¹, Sreyashi Debnath ¹, Rachana G. Kulkarni ¹, Stefano Alessandrini ², Mrinal Biswas ², Santosh Kulkrani ³, Prakash Pithani ¹, Saurab Kelkar ¹, Veeresh Sajjan ¹, D. M. Chate ¹, V. K. Soni ⁴, Siddhartha Singh ⁴, Ravi S. Nanjundiah ¹, M. Rajeevan ⁵

Affiliations
1 Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune 411 008, IN
2 National Center for Atmospheric Research, Boulder, CO 80301, US
3 Centre for Development of Advanced Computing, Pune 411 008, IN
4 India Meteorological Department, Ministry of Earth Sciences, New Delhi 110 003, IN
5 Ministry of Earth Sciences, Government of India, New Delhi 110 003, IN

Abstract

Air quality has become one of the most important environmental concerns for Delhi, India. In this perspective, we have developed a high-resolution air quality prediction system for Delhi based on chemical data assimilation in the chemical transport model – Weather Research and Forecasting with Chemistry (WRF-Chem). The data assimilation system was applied to improve the PM2.5 forecast via assimilation of MODIS aerosol optical depth retrievals using threedimensional variational data analysis scheme. Near real-time MODIS fire count data were applied simultaneously to adjust the fire-emission inputs of chemical species before the assimilation cycle. Carbon monoxide (CO) emissions from biomass burning, anthropogenic emissions, and CO inflow from the domain boundaries were tagged to understand the contribution of local and non-local emission sources. We achieved significant improvements for surface PM2.5 forecast with joint adjustment of initial conditions and fire emissions.

Keywords

Air Quality, Particulate Matter, Chemical Data Assimilation, Aerosol Optical Depth, Fire Emissions.

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P. S. Yadav ¹, N. L. Selokar ¹, D. Kumar ¹, R. K. Sharma ¹, P. Kumar ¹, Rajesh Kumar ¹, M. Saini ¹, S. Dua ¹

Affiliations
1 Division of Animal Physiology and Reproduction, ICAR-Central Institute for Research on Buffaloes, Hisar 125 001, IN

Abstract

No Abstract.

Keywords

No Keywords.

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Prajjwal Rawat ¹, Manish Naja ¹, Pradeep K. Thapliyal ², Shuchita Srivastava ³, Piyush Bhardwaj ⁴, Rajesh Kumar ⁴, Samaresh Bhatacharjee ¹, S. Venkatramani ⁵, S. N. Tiwari ⁶, Shyam Lal ⁵

Affiliations
1 Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital 263 002, IN
2 Space Applications Centre, Jodhpur Tekra, Ahmedabad 380 015, IN
3 Indian Institute of Remote Sensing, 4 Kalidas Road, Dehradun 248 001, IN
4 National Center for Atmospheric Research, 3450 Mitchell Lane, Boulder, CO 80301, US
5 Physical Research Laboratory, Navrangpura, Ahmedabad 380 009, IN
6 DDU Gorakhpur University, Gorakhpur 273 009, IN

Abstract

Vertical distribution of ozone has been obtained for the first time using INSAT-3D for the period 2013-2017 over the central Himalaya and validated utilizing balloon-borne observations from a high-altitude site in Nainital (29.4°N, 79.5°E, 1793 m amsl). The INSAT-3D retrieved ozone profiles captured ozone gradient and ozone peak altitude successfully, despite only one IR channel for ozone. This demonstrates the capability of the INSAT-3D Sounder in capturing the observed features, with a smaller bias in the stratosphere and somewhat larger bias in the troposphere. Total ozone column from INSAT-3D showed maximum difference of 8% with ozonesonde-derived total ozone column. Larger ozone bias in the lower troposphere could be attributed to lower reliability of regression coefficient and INSAT-3D channel constraints itself, whereas high variability near the tropopause is possibly due to low ozone, poor temperature retrieval near the tropo-pause and stratosphere–troposphere transport process in the Himalayan region.

Keywords

Ozone Profiles, Ozonesonde, Satellite Data, Vertical Distribution.

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