M. S. Rao

Identifying Salinization Using Isotopes and Ion Chemistry in Semi-Arid Region of Punjab, India

The Semi-arid Southwest part of the Punjab has intense agricultural and industrial activity and this part is affected by groundwater salinity problems. To identify the groundwater salinity using isotopes (δ18O) and ion chemistry 22 random samples were collected from semi-arid region of South West Punjab i.e. Bhatinda district. The hydro-chemical analysis shows that the southern and western parts have high values of EC. Some areas in the district especially in north, central and small patches in south-western and eastern parts showing high values of fluoride exceeding the permissible limit of 1.5 mgL-1 for drinking water standards. The water belongs to the category of very hard water. The Na% in groundwater indicates that from 17 groundwater water sampling locations water can be used for irrigation leaving only 5 sampling locations which is found unsuitable for irrigation. The enriched δ18O values are found in the eastern and western parts of the district, while southern and northern parts are showing highly depleted values. The enriched values found between the canals Bhatinda branch and Kotla branch may be attributed to evaporation from shallow water table areas. The enriched δ18O values of groundwater are indicator of salinity. There is an increase in EC and enrichment in isotopic composition as observed in some samples due to the evaporation effect and in some samples the increase is EC is found but the isotopic composition remains constant indicating the increase in EC due to geogenic reasons. Therefore, the integrated data of ion chemistry and isotope is useful for identifying the salinity in semi-arid region.

Estimation of radon concentration in groundwater of coastal area in Baleshwar district of Odisha, India

The present study was carried out to determine the distribution of radon (222Rn) activity concentration measured using Durridge RAD-7 in the groundwater samples in the coastal area of Baleshwar district, Odisha, India. The 222Rn activities in 10 groundwater samples of coastal area of Baleshwar were measured and the values of 222Rn ranged between 1.6 ± 0.21 and 17.0 ± 1.69 kBq m−3 with an average value of 8.98 ± 0.85 kBq m−3, and seven samples were well within the Environmental Protection Agencys maximum contaminant level of 11.1 kBq m−3 while three samples were more than the maximum contaminant level of 11.1 kBq m−3. The effective dose per m3 and annual effective dose values were varying with respect to the increase in radon concentration and were significantly lower than the United Nations Scientific Committee on the Effects of Atomic Radiation and WHO recommended limit for members of the public of 1 mSv y−1.

Observing changes in groundwater resource using hydro-chemical and isotopic parameters: a case study from Bist Doab, Punjab

Abstract The continuous and large-scale abstraction of groundwater has created a groundwater depletion problem in several parts of the Punjab state including Bist Doab, the interfluve region of Beas and Satluj rivers. In the present study, a few important parameters, viz. water level, stable isotope, EC, temperature, groundwater age, that can be used to fingerprint the over-exploitation of groundwater have been examined. It has been observed that with the increase in over-exploitation, the yield of shallow aquifer is progressively getting reduced and as a result forcing the farmers to sink their wells to deeper depths. With abstraction of deeper aquifer, the storage of old groundwater at the deeper aquifer is declining and getting replaced by induced accelerated inflow of young water from the recharge zone and the overlying shallow aquifer. The signatures of the modern water have been observed in the data analyzed for isotopic, hydro-chemical facies, electrical conductivity and temperature of water from deeper aquifer. The study has identified the usefulness of these parameters for identifying groundwater over-exploitation in the region. Depleting water resource may stagnate the economic progress of the region. The paper provides suitable water resource management strategies to be adopted to improve the sustainability of water resources and economic growth in the region.

Groundwater Fluctuation and Trend in Amritsar, Punjab, India

Punjab state in the northwestern part of India constitutes 1.57% of total area in the country and its economy is mainly controlled by agriculture by covering 85% of geographical area with cropping intensity reaching to 184% in the central parts of the state. During last 4 decades a shift from Sugarcane-Maize-Wheat cropping pattern to Wheat-Rice cropping pattern has lead to increase in the demand for irrigation water and further putting stress on the groundwater. Groundwater level monitoring has been carried out on 4 observation wells in 4 blocks namely Ajnala, Majitha, Rayya and Tarsika of Amritsar for 7 years during January 2006 to December 2013 for assessing the groundwater level. Groundwater occurs under phreatic condition and depth to groundwater varied from 6 to 11 m (bgl) in Ajnala, 5 to 11 m (bgl) in Majitha, 14 to 19 m (bgl) in Rayya and 9 to 14 m (bgl) in Tarsika. The increased depth of 6 m was observed in Majitha and 5 m was observed in other 3 blocks. Monthly groundwater level data have been analysed which indicates that the ground water is declining in all the four blocks with variable rate. The decline of groundwater level in each block during 7 years has become an area of concern for understanding the over exploitation of groundwater scenario in the region.

Isotopic Observations from Two Stations of North India to Investigate Geographical Effects on Seasonal Air Moisture

Air moisture samples were collected from 2 stations of north India for the years 2012 and 2013: one located in high Himalayas inMarhi, Manali, Himachal Pradesh and second in Indo-gangetic plains of Roorkee, Uttarakhand using condensation method for studying seasonal variations in isotopic composition. In high Himalayas, the air moisture was found isotopically more enriched (δD) as compared to the moisture collected in Indo-gangetic plains. But due to the arrival of oceanic vaporduring the monsoon season, the isotopic values start getting depleted whichopens up the possibility to use isotopic composition of air moisture for seasonal studies.

Assessment of Salinity and Fluoride in Groundwater of Semi-Arid Region of Punjab, India

Groundwater is the major source of drinking water in Southwestern semi-arid region of Punjab, India which is now facing severe salinity and fluoride (F-) problems. A study was carried out in the Bathinda district of southwest semi-arid region of Punjab to assess the salinity and Fconcentrations. Groundwater samples from 21 locations were analyzed, and 59% were found to exceed the permissible electrical conductivity (EC) limit of 1500 μS/cm1. Fluoride concentrations exceeded the WHO (2008)1 permissible limit of 1.50 mg/L in 69% of the samples which may significantly affect human health by causing fluorosis. The increase in groundwater levels leading to high evaporation which caused an accumulation of salts and further resulted in increase in EC. The increased Fconcentration is mainly due to rock-water interactions which led to fluorite dissolution.

Application of Isotopes in Studying Lake Water – Groundwater Interactions in Parts of Tumkur District of Karnataka

In the present study, to demonstrate use of combined isotopic and salinity mapping in understanding local scale groundwater-surface water conditions the water samples were collected from 4 nos. of defined lakes (Kadaba, Belavatta, Pura and Nittur); groundwater samples were collected from shallow hand pumps/tube wells along the periphery of the lakes. The rain samples were also collected. The lake water appears to get enriched in its isotopic composition mainly due to evaporation in this region. Lake water salinities are lower compared to nearby groundwater salinity. The flow of groundwater, recharged at Nittur lake, continues to its downstream at least till Pura. Increase in salinity of groundwater is seen between the points Pura-groundwater & surface water (may be due to dissolution of sub-surface soil). The groundwater sampled at Belavatta is found to be recharged from local precipitation and not from surface body. The water body (Kadaba) is getting filled mainly due to precipitation and to some extent due to runoff from the upper reach of water body. There is a strong link between lake water–groundwater (e.g. site Pura) and groundwater–lake water (e.g. Site Kadaba). Therefore, this procedure is expected to radically increase the accountability of usage and help in planning of suitable ground water supply and would provide a holistic approach to promote maximum agricultural output and industrial growth.

Understanding the Seasonal Dynamics of the Groundwater Hydrogeochemistry in National Capital Territory (NCT) of India Through Geochemical Modelling

A geochemical assessment of seasonal dynamics in the groundwater chemistry of the National Capital Territory (NCT), Delhi, was attempted through geochemical modelling, mineral precipitation sequences with rainfall and water evaporation cycle. Saturation indices calculated using PHREEQC indicated that the degree of water–rock equilibrium changes significantly from pre-monsoon to post-monsoon. The schematic model of SI change with water table fluctuation showed that during monsoon, as rainwater percolates through the soil, partial pressure of CO2 becomes higher than that of the atmospheric value and led to the formation of more carbonic acid that react with the carbonate minerals to produce

Radon concentration in groundwater of east coast of West Bengal, India

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