scholarly journals Cyclic behavior of late quaternary alluvial soil along Indo-Gangetic Plain: Northern India

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Sambit Prasanajit Naik ◽  
Nihar Ranjan Patra ◽  
Javed N. Malik
Keyword(s):  
Late Quaternary ◽  
Alluvial Soil ◽  
Confining Pressure ◽  
Cyclic Strength ◽  
Cyclic Behavior ◽  
Triaxial Tests ◽  
Gangetic Plain ◽  
Northern India ◽  
Historical Past ◽  
Indo Gangetic Plain

AbstractThe A.D. 1803 and 1934 Bihar-Nepal border earthquake affected Indo-Gangetic Plain with evidences of liquefaction in cities like Patna, Varanasi, Agra, and Delhi in historical past. Recent strong shaking all along the Indo-Gangetic Plains and seismic induced damage to the buildings in Bihar during Mw 7.8 Gorkha earthquake raises the concern for site specific liquefaction potential estimation of alluvial soils. Cyclic triaxial tests were conducted on soil samples from Kanpur, Allahabad, Patna city to know the cyclic behavior, estimate the dynamic soil properties and the effect of relative density, confining pressure and frequency of loading on the cyclic behavior of the soil tested. The test results indicate the cyclic strength of Allahabad soil is less than Patna and Kanpur soil. The Allahabad soil with 80% sand, 10% silt and clay each is more prone to liquefaction than Kanpur soil (82% silt, 16% clay and 2% sand) and Patna soil (10% Kankar, 95% sand, 5% silt). This study indicates soils having sand with silt percentage are more liquefiable than clean sand or silty soil. It can be concluded that the soil of Allahabad and Patna city is more prone to liquefaction than Kanpur soil.

scholarly journals Measurement report: Regional characteristics of seasonal and long-term variations in greenhouse gases at Nainital, India, and Comilla, Bangladesh

2021 ◽  
Vol 21 (21) ◽  
pp. 16427-16452
Author(s):  
Shohei Nomura ◽  
Manish Naja ◽  
M. Kawser Ahmed ◽  
Hitoshi Mukai ◽  
Yukio Terao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Mole Fraction ◽  
Biomass Burning ◽  
Climatic Conditions ◽  
Gangetic Plain ◽  
Air Mass ◽  
Regional Characteristics ◽  
Northern India ◽  
Indo Gangetic Plain

Abstract. Emissions of greenhouse gases (GHGs) from the Indian subcontinent have increased during the last 20 years along with rapid economic growth; however, there remains a paucity of GHG measurements for policy-relevant research. In northern India and Bangladesh, agricultural activities are considered to play an important role in GHG concentrations in the atmosphere. We performed weekly air sampling at Nainital (NTL) in northern India and Comilla (CLA) in Bangladesh from 2006 and 2012, respectively. Air samples were analyzed for dry-air gas mole fractions of CO2, CH4, CO, H2, N2O, and SF6 and carbon and oxygen isotopic ratios of CO2 (δ13C-CO2 and δ18O-CO2). Regional characteristics of these components over the Indo-Gangetic Plain are discussed compared to data from other Indian sites and Mauna Loa, Hawaii (MLO), which is representative of marine background air. We found that the CO2 mole fraction at CLA had two seasonal minima in February–March and September, corresponding to crop cultivation activities that depend on regional climatic conditions. Although NTL had only one clear minimum in September, the carbon isotopic signature suggested that photosynthetic CO2 absorption by crops cultivated in each season contributes differently to lower CO2 mole fractions at both sites. The CH4 mole fraction of NTL and CLA in August–October showed high values (i.e., sometimes over 4000 ppb at CLA), mainly due to the influence of CH4 emissions from the paddy fields. High CH4 mole fractions sustained over months at CLA were a characteristic feature on the Indo-Gangetic Plain, which were affected by both the local emission and air mass transport. The CO mole fractions at NTL were also high and showed peaks in May and October, while CLA had much higher peaks in October–March due to the influence of human activities such as emissions from biomass burning and brick production. The N2O mole fractions at NTL and CLA increased in June–August and November–February, which coincided with the application of nitrogen fertilizer and the burning of biomass such as the harvest residues and dung for domestic cooking. Based on H2 seasonal variation at both sites, it appeared that the emissions in this region were related to biomass burning in addition to production from the reaction of OH and CH4. The SF6 mole fraction was similar to that at MLO, suggesting that there were few anthropogenic SF6 emission sources in the district. The variability of the CO2 growth rate at NTL was different from the variability in the CO2 growth rate at MLO, which is more closely linked to the El Niño–Southern Oscillation (ENSO). In addition, the growth rates of the CH4 and SF6 mole fractions at NTL showed an anticorrelation with those at MLO, indicating that the frequency of southerly air masses strongly influenced these mole fractions. These findings showed that rather large regional climatic conditions considerably controlled interannual variations in GHGs, δ13C-CO2, and δ18O-CO2 through changes in precipitation and air mass.

scholarly journals Black Carbon physical and optical properties across northern India during pre-monsoon and monsoon seasons

2019 ◽  
Author(s):  
James Brooks ◽  
Dantong Liu ◽  
James D. Allan ◽  
Paul I. Williams ◽  
Jim Haywood ◽  
...  
Keyword(s):  
Physical Properties ◽  
Black Carbon ◽  
Mixing State ◽  
Atmospheric Measurements ◽  
Core Diameter ◽  
Gangetic Plain ◽  
North West ◽  
North East ◽  
Northern India ◽  
Indo Gangetic Plain

Abstract. Black carbon (BC) is known to have major impacts on both climate and human health, so is therefore of global importance, particularly so in regions close to large populations that have strong sources. The physical properties and mixing state of black carbon containing particles are important determinants in these effects but information is often lacking, particularly in some of the most important regions of the globe. Detailed analysis into the vertical and horizontal BC optical and physical properties across northern India has been carried out using airborne in-situ measurements. The size-resolved mixing state of BC-containing particles was characterised using a single particle soot photometer (SP2). The study focusses on the Indo-Gangetic Plain during the pre-monsoon and monsoon seasons. Data presented are from the UK Facility for Airborne Atmospheric Measurements BAe-146 research aircraft that performed flights during the pre-monsoon (11th and 12th June) and monsoon (30th June to 11th July) seasons of 2016. Over the Indo-Gangetic Plain, BC mass concentrations were greater (1.95 µg/m3) compared to north-west India (1.50 µg/m3) and north-east India (0.70 µg/m3) during the pre-monsoon. Across northern India, two distinct BC modes were recorded; a mode of small BC particles (core diameter 

Liquefaction Testing of Stratified Sands Interlayered with Silt

2012 ◽  
Vol 256-259 ◽  
pp. 116-119 ◽  
Author(s):  
Min Cai Jia ◽  
Bing Ye Wang
Keyword(s):  
Critical Thickness ◽  
Confining Pressure ◽  
Cyclic Behavior ◽  
Triaxial Tests ◽  
Experimental Program ◽  
Cyclic Triaxial Tests ◽  
Hydraulic Fill ◽  
Soil Deposits ◽  
History Of ◽  
Different Thickness

The cyclic behavior of stratified sands interlayered with silt is at present poorly understood, although stratified sands exist for various soil deposits and hydraulic fill, which have a history of liquefaction during earthquakes. The main objective of this research project was to compare the cyclic behavior of stratified and homogeneous sands for various silt contents. A comprehensive experimental program was undertaken in which stain-controlled undrained cyclic triaxial tests for stratified sand samples interlayered with different thickness silt were performed. The silt thickness ranged from 0 to 80mm was considered. The confining pressure in all test series was 100kPa. The results indicate that the thickness of the silt seam sandwiched in the sand samples has a significant influence on the liquefaction resistances of layered sands. In other words, there is a critical thickness of silt seam that the saturated stratified sands have a critical shear strain. This finding justifies applying the laboratory tests results of homogeneously reconstituted samples to the field conditions for the range of variable studied.

scholarly journals A parametric study on cyclic strength of coastal sand of Digha in West Bengal, India

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pinak Ray ◽  
Ramendu Bikas Sahu
Keyword(s):  
West Bengal ◽  
Confining Pressure ◽  
Cyclic Stress ◽  
Cyclic Strength ◽  
Triaxial Tests ◽  
Cyclic Stress Ratio ◽  
Confining Pressures ◽  
Coastal Sand ◽  
Number Of Cycles

AbstractStress controlled cyclic triaxial tests have been carried out on coastal sand of Digha, West Bengal, India at different frequencies, confining pressures, relative densities and number of loading cycles for determination of influence of these parameters on cyclic strength (expressed in terms of cyclic stress ratio) and initial liquefaction of Digha sand. The test results provide evidence that increasing density of sand increases liquefaction potential, though it has been found that increase in effective confining pressure reduces cyclic strength of sand. Cyclic strength of sand decreases with increase of number of loading cycles at a specific density and a particular confining pressure. It has been observed that frequency of loading cycles does have any significant influence on the number of cycles for initial liquefaction of Digha sand. An empirical correlation has been developed on cyclic strength of sand based on these parameters and it has been found that this correlation fits quite well with the observed experimental results.

Effect of N, P and K fertilizers on the availability of native and applied manganese to wheat

1973 ◽  
Vol 81 (3) ◽  
pp. 369-373 ◽  
Author(s):  
B. Mishra ◽  
B. R. Tripathi
Keyword(s):  
Field Experiment ◽  
Ammonium Sulphate ◽  
Crop Yield ◽  
Alluvial Soil ◽  
Pronounced Effect ◽  
Gangetic Plain ◽  
P Fertilizer ◽  
Indo Gangetic Plain ◽  
Muriate Of Potash ◽  
K Fertilization

SUMMARYThe influence of three rates of each of N, P and K fertilizers on the availability of native and applied Mn to wheat was studied in a field experiment on an alluvial soil of the Indo-Gangetic plain. Increasing dressings of N as ammonium sulphate resulted in consistently higher yields and Mn uptake by the crop. Concentration of Mn in the grain increased with increasing N dressings when native Mn and Mn fertilizer supplied this nutrient but it was unaffected inplants sprayed with Mn. Adding P as superphosphate tended to lower the concentration of Mn in the grain when relying on native or applied Mn but it significantly enhanced the crop yield and total Mn uptake. Applying K as muriate of potash slightly depressed Mn uptake by plants. Potassium had a more pronounced effect in the absence of P fertilizer. The concentration of Mn in thestraw was not significantly affected by N, P and K fertilization.

scholarly journals Measurement report: Regional characteristics of seasonal and long-term variations in greenhouse gases at Nainital, India and Comilla, Bangladesh

2021 ◽  
Author(s):  
Shohei Nomura ◽  
Manish Naja ◽  
Md. Kawser Ahmed ◽  
Hitoshi Mukai ◽  
Yukio Terao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Mole Fraction ◽  
Biomass Burning ◽  
Climatic Conditions ◽  
Co2 Absorption ◽  
Gangetic Plain ◽  
Regional Characteristics ◽  
Northern India ◽  
Indo Gangetic Plain

Abstract. Emissions of greenhouse gases (GHGs) from the Indian subcontinent have increased during the last 20 years along with rapid economic growth, however, there remains a paucity of GHG measurements for policy relevant research. In northern India and Bangladesh, agricultural activities are considered to play an important role on GHGs concentrations in the atmosphere. We performed weekly air sampling at Nainital (NTL) in northern India and Comilla (CLA) in Bangladesh from 2006 and 2012, respectively. Air samples were analyzed for dry-air gas mole fractions of CO2, CH4, CO, H2, N2O, and SF6, and carbon and oxygen isotopic ratios of CO2 (δ13C-CO2 and δ18O-CO2). Regional characteristics of these components over the Indo-Gangetic Plain are discussed compared to data from other Indian sites and Mauna Loa, Hawaii (MLO), which is representative of marine background air. We found that the CO2 mole fraction at both NTL and CLA had two seasonal minima in February‒March and September, corresponding to crop cultivation activities that depend on regional climatic conditions. The carbon isotopic signature also suggested that photosynthetic CO2 absorption by crops cultivated in each season contributes differently to lower CO2 mole fractions. The CH4 mole fraction of NTL and CLA in August‒October showed high values (i.e., sometimes over 4,000 ppb at CLA) due to the influence of CH4 emissions from the paddy fields in addition to the other sources due to the hot and humid climatic conditions. High CH4 mole fractions sustained over months at CLA were a characteristic feature in the Indo-Gangetic Plain. The CO mole fractions at NTL were also high and showed peaks in May and October, while CLA had much higher peaks in October‒March due to the influence of human activities such as emissions from biomass burning and brick production. The N2O mole fractions at NTL and CLA increased in June‒August and November‒February, which coincided with the application of nitrogen fertilizer and the burning of biomass such as the harvest residues and dung for domestic cooking. Based on H2 seasonal variation at both sites, it appeared that the emissions in this region were related to biomass burning in addition to production from the reaction of OH and CH4. The SF6 mole fraction was similar to that at MLO, suggesting that there were few anthropogenic emission sources in the district. The variability of CO2 growth rate at NTL was different from the variability in the CO2 growth rate at MLO, which is more closely linked with the El Niño Southern Oscillation (ENSO). In addition, the growth rates of the CH4 and SF6 mole fractions at NTL showed an anticorrelation with those at MLO, indicating that the frequency of southerly air masses strongly influenced these mole fractions. These finding showed that rather large regional climatic conditions considerably controlled interannual variations in GHGs, δ13C-CO2, and δ18O-CO2 through changes in precipitation and air mass.

scholarly journals The Dominant Modes of Recycled Monsoon Rainfall over India

2017 ◽  
Vol 18 (10) ◽  
pp. 2647-2657 ◽  
Author(s):  
K. Sujith ◽  
Subodh Kumar Saha ◽  
Samir Pokhrel ◽  
Anupam Hazra ◽  
Hemantkumar S. Chaudhari
Keyword(s):  
Water Vapor ◽  
Monsoon Rainfall ◽  
Central India ◽  
Atmospheric Water Vapor ◽  
Western Himalayas ◽  
Atmospheric Water ◽  
Gangetic Plain ◽  
External Influences ◽  
Northern India ◽  
Indo Gangetic Plain

Abstract This study estimates the seasonal mean (June–September) recycled rainfall and investigates its dominant modes of variability over the continental regions of the Indian summer monsoon. A diagnostic method based on the basic atmospheric water vapor budget equation is employed in order to partition the observed rainfall into recycled and advected components. The global teleconnections with the recycled (advected) rainfall are found to be weak (strong), which is consistent with the basic assumptions of the sources of atmospheric water vapor. It is shown that the mean recycled rainfall over the Indo-Gangetic Plain, central India, and western Himalayas ranges between 10% and 40% of the total rainfall. While EOF1 (38.5%) of the recycled rainfall reveals covariability between the regional and external influences, EOF2 (14%) shows a mode independent to the external influences (i.e., advected rainfall), prevailing over the Indo-Gangetic Plain. Furthermore, a strong decreasing trend in PC2 over the last 36 years suggests a change in the local feedback (land, atmosphere), which in turn may have also contributed to the decreasing trend in the observed monsoon rainfall over central and northern India.

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