| 1. |
- Kumar, Rajesh, et al.
(författare)
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Development of a Glacio-hydrological Model for Discharge and Mass Balance Reconstruction
- 2016
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Ingår i: Water resources management. - : Springer Science and Business Media LLC. - 0920-4741 .- 1573-1650. ; 30:10, s. 3475-3492
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Tidskriftsartikel (refereegranskat)abstract
- The reconstruction of glacio-hydrological records for the data deficient Himalayan catchments is needed in order to study the past and future water availability. The study provides outcomes of a glacio-hydrological model based on the degree-day approach. The model simulates the discharge and mass balance for glacierised Shaune Garang catchment. The degree-day factors for different land covers, used in the model, were estimated using daily stake measurements on Shaune Garang glacier and they were found to be varying between 2.6 ± 0.4 and 9.3 ± 0.3 mm °C−1day−1. The model is validated using observed discharge during ablation season of 2014 with coefficient of determination (R2) 0.90 and root mean square error (RMSE) 1.05 m3 sec−1. The model is used to simulate discharge from 1985 to 2008 and mass balance from 2001 to 2008. The model results show significant contribution of seasonal snow and ice melt in total discharge of the catchment, especially during summer. We observe the maximum discharge in July having maximum contribution from snow and ice melt. The annual melt season discharge shows following a decreasing trend in the simulation period. The reconstructed mass balance shows mass loss of 0.89 m we per year between 2001 and 2008 with slight mass gain during 2000/01 and 2004/05 hydrological years.
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| 2. |
- Gupta, Rajeev Kumar, et al.
(författare)
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Influence of 11 years of crop residue management on rice productivity under varied nitrogen levels in the rice-wheat cropping system
- 2023
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Ingår i: Plant, Soil and Environment (Praha). - : Czech Academy of Agricultural Sciences. - 1214-1178 .- 1805-9368. ; 69:7, s. 333-343
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Tidskriftsartikel (refereegranskat)abstract
- The present study compares the six crop residue management techniques in main plots (since 2008) and three split nitrogen (N) levels, i.e., 75, 100 and 125 kg N/ha in subplots for rice crops for two years, i.e., 2019 and 2020, in sandy loam soil under field conditions. This experiment evaluated the long-term effect on rice productivity, soil organic carbon content and nutrient requirement in rice-wheat cropping system. The results revealed that different crop residue management practices and N levels significantly influenced rice growth, yield and yield attributes and improved nutrient uptake by grain and straw. Maximum grain yields of 20.8% and 17.8% higher over the conventional (no straw) treatment during 2019 and 2020, respectively, were recorded where the rice and wheat residue was re-tained or incorporated. The rice grain yield without residue responded significantly up to 125 kg N/ha. Whereas, with rice and wheat residue, rice grain yield did not respond to the application of N beyond 75 kg N/ha during both years.
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| 3. |
- Krishan, Gopal, et al.
(författare)
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Isotopes (6(18)O,6D and H-3) variations in groundwater with emphasis on salinization in the state of Punjab, India
- 2021
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 789
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Tidskriftsartikel (refereegranskat)abstract
- The state of Punjab has a dominant agrarian economy and is considered India's bread basket. However, it is now under the problem of falling agro-economy primarily because of pervasive depletion of groundwater levels and deteriorating groundwater quality in south-west Punjab, but increasing salinity is a major concern. The irrigation requirements of crops are fulfilled by groundwater and canal water but the introduction of canal irrigation has led to waterlogging and subsequent salinization rendering large fertile-land areas becoming unproductive mainly in the south-western part of Punjab. There was an apprehension that excessive withdrawal of groundwater might have caused a reversal of natural groundwater flow pattern that might have caused ingress of saline water into fresh groundwater region of central Punjab. To address the apprehension related to the rise in groundwater salinity and its subsequent ingression in the fresh-water zone and suggest suitable management solutions, a study was undertaken to analyse the data related to salinity, isotopes, land-use and land cover (LULC) along with field and laboratory experimental results. The depth-wise isotope analysis shows that there is a large variation in isotopic signatures of shallow and intermediate aquifers and it decreases with the depth of aquifers (150-250 m). It appears that very deep groundwater (>250 m) is relatively isolated and does not show a large variation or mixing effect. Tritium analysis shows that dynamic groundwater is actively recharged through canal, river, and/or rain. The presence of modern groundwater at deeper depth indicates a good interconnection between shallow and deep groundwater. Interpretations of the results show that the canal is the main source of groundwater recharge in south-west Punjab and the evaporation process is responsible for increasing the salinity hazard. In the central parts of Punjab, groundwater and rain are the main sources of groundwater recharge, while rain is the main source of groundwater recharge in the Kandi area. In the south-west Punjab, some primary salinity has formed as a result of mineral dissolution which has further increased due to evaporative enrichment.
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| 4. |
- Krishan, Gopal, et al.
(författare)
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Occurrences of potentially toxic trace metals in groundwater of the state of Punjab in northern India
- 2021
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Ingår i: GROUNDWATER FOR SUSTAINABLE DEVELOPMENT. - : Elsevier BV. - 2352-801X. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- In present study, a total of 275 representative water samples (263 groundwater, 8 canal water, 2 samples from Sutlej River and 2 samples from Buddha Nala) were collected and analysed. The sampling was carried out in the month of August, September, and October of 2019. These samples were analysed for the Arsenic (As-total), Aluminium (Al), Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Chromium (Cr), Cadmium (Cd), Nickel (Ni), and Lead (Pb). The result found that 3.8 % of the analysed groundwater samples have As concentrations above acceptable limit (10 mu g/L) and similar to 0.38 % samples exceeded the permissible limit of 50 mu g/L. Iron concentration exceeded the acceptable limit of 0.3 mg/L for drinking water in similar to 14.83 % groundwater samples. The mean concentration of iron was found 252 mu g/L and 3810 mu g/L for groundwater and canal water, respectively. It was observed that some samples have concentrations more than acceptable limits in the cities of Ludhiana, SBS Nagar, Rupnagar, SAS Nagar districts and in parts of Mansa, Amristar and Gurdaspur districts of the state of Punjab. Iron was found exceeding the permissible limit in the villages like, Moran wara (Firozepur), Churian (Firozepur), Manewal (Ludhiana), PandKhokhan (Muktsar) and Pakki Kalan (Faridkot).
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| 5. |
- Abend, Sven, et al.
(författare)
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Terrestrial very-long-baseline atom interferometry : Workshop summary
- 2024
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Ingår i: AVS Quantum Science. - : American Institute of Physics (AIP). - 2639-0213. ; 6:2
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Forskningsöversikt (refereegranskat)abstract
- This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.
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