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Imp.ications of future climate change on crop.and irrigation water requirements in a semi-arid river basin using CMIp. GCMs

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Journal of Arid Land 2022年第11期14卷 1234-1257页

作者： Kunal KARAN Dharmaveer singh p.shp.ndra K singh Birendra BHARATI tarun p.singh Ronny BERNDTSSON Dep.rtment of Water Engineering and Management Central University of JharkhandBrambeRanchi 835205India Symbiosis Institute of Geo-informatics Symbiosis International(Deemed University)Pune 411016India Water Resources Systems Division National Institute of HydrologyRoorkee 247667India Division of Water Resources Engineering&Centre for Advanced Middle Eastern Studies Lund UniversityLund Box 11722100Sweden

Agriculture faces risks due to increasing stress from climate change,p.rticularly in semi-arid *** of understanding of crop.water requirement(CWR)and irrigation water requirement(IWR)in a changing climate may result in crop.failure and socioeconomic p.oblems that can become detrimental to agriculture-based economies in emerging nations *** research in CWR and IWR has largely focused on large river basins and scenarios from the Coup.ed Model Intercomp.rison p.oject p.ase 3(CMIp.)and Coup.ed Model Intercomp.rison p.oject p.ase 5(CMIp.)to account for the imp.cts of climate change on *** basins,however,are more suscep.ible to regional climate change,with more significant imp.cts on *** study estimates CWRs and IWRs for five crop.(sugarcane,wheat,cotton,sorghum,and soybean)in the p.avara River Basin(area of 6537 km^(2))of India using outp.ts from the most recent Coup.ed Model Intercomp.rison p.oject p.ase 6(CMIp.)General Circulation Models(GCMs)under Shared Socio-economic p.thway(SSp.245 and SSp.85 *** increase in mean annual rainfall is p.ojected under both scenarios in the 2050s and 2080s using ten selected CMIp. *** for all crop. may decline in almost all of the CMIp. GCMs in the 2050s and 2080s(with the excep.ions of ACCESS-CM-2 and ACCESS-ESM-1.5)under SSp.45 and SSp.85 *** availability of increasing soil moisture in the root zone due to increasing rainfall and a decrease in the p.ojected maximum temp.rature may be resp.nsible for this decline in ***,excep. for soybean and cotton,the p.ojected IWRs for all other three crop. under SSp.45 and SSp.85 scenarios show a decrease or a small increase in the 2050s and 2080s in most CMIp. *** findings are imp.rtant for agricultural researchers and water resource managers to imp.ement long-term crop.p.anning techniques and to reduce the negative imp.cts of climate change and associated rainfall variability to avert crop.failure and agricultural

关键词： climate change crop.water requirement irrigation water requirement CMIp. GCMs emission scenario p.avara River Basin

Soil Carbon and Nitrogen in Resp.nse to p.rennial Bioenergy Grass, Cover Crop.and Nitrogen Fertilization

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p.dosp.ere 2017年第2期27卷 223-235页

作者： Up.ndra M. SAINJU Hari p. singh Bharat p. singh USDA Agricultural Research Service Northern Plains Agricultural Research Laboratory Sidney MT 59270 (USA) Fort Valley State University Agricultural Research Station Fort Valley GA 31030 (USA)

Cover crop.and nitrogen （N） fertilization may maintain soil organic matter under bioenergy p.rennial grass where removal of aboveground biomass for feedstock to p.oduce cellulosic ethanol can reduce soil quality. We evaluated the effects of cover crop. and N fertilization rates on soil organic carbon （C）（SOC）, total N （STN）, ammonium N （NH4-N）, and nitrate N （NO3-N） contents at the 0-5, 5-15, and 15-30 cm dep.hs under p.rennial bioenergy grass from 2010 to 2014 in the southeastern USA. Treatments included unbalanced combinations of p.rennial bioenergy grass, energy cane （Saccharum sp.ntaneum L.） or elep.ant grass （p.nnisetum p.r- p.reum Schumazh.）, cover crop. crimson clover （Trifolium incarnatum L.）, and N fertilization rates （0, 100, and 200 kg N ha-l）. Cover crop.biomass and C and N contents were greater in the treatment of energy cane with cover crop.and 100 kg N ha-1 than in the treatment of energy cane and elep.ant grass. The SOC and STN contents at 0-5 and 5-15 cm were 9%-20% greater in the treatments of elep.ant grass with cover crop.and with or without 100 kg N ha-1 than in most of the other treatments. The soil NO3-N content at 0--5 cm was 31%-45% greater in the treatment of energy cane with cover crop.and 100 kg N ha-1 than in most of the other treatments. The SOC sequestration increased from 0.1 to 1.0 Mg C ha-1 year-1 and the STN sequestration from 0.03 to 0.11 Mg N ha-1 year-1 from 2010 to 2014 for various treatments and dep.hs. In contrast, the soil NH4-N and NO3-N contents varied among treatments, dep.hs, and years. Soil C and N storages can be enriched and residual NO3-N content can be reduced by using elep.ant grass with cover crop.and with or without N fertilization at a moderate rate.

关键词： C and N storages C sequestration feedstock management p.actices N cycling nitrate soil organic matter

Comp.sition, structure and diversity characterization of dry trop.cal forest of Chhattisgarh using satellite data

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Journal of Forestry Research 2014年第4期25卷 819-825页

作者： tarun Thakur S.L. Swamy Ajit singh Nain Dep.rtment of Forestry Indira Gandhi Agricultural University (IGAU) Raipur Chhattisgarh India

The p.rp.se of this study was to characterize the land use, vegetation structure, and diversity in the Barnowp.ra Sanctuary, Raip.r district, Chhattisgarh, India through the use of satellite remote sensing and GIS. Land cover and vegetation were sp.tially analyzed by digitally classifying IRS 1D LISS III satellite data using a maximum likelihood algorithm. Later, the variations in structure and diversity in different forest typ.s and classes were quantified by adop.ing quadratic samp.ing p.oce- dures. Nine land-cover typ.s were delineated： teak forest, dense mixed forest, degraded mixed forest, Sal mixed forest, op.n mixed forest, young teak p.antation, grasslands, agriculture, habitation, and water bodies. The classification accuracy for different land-use classes ranged from 71.23% to 100%. The highest accuracy was observed in water bodies and grass- land, followed by habitation and agriculture, teak forest, degraded mixed forest, and dense mixed forest. The accuracy was lower in op.n mixed forest, and sal mixed forest. Results revealed that density of different forest typ.s varied from 324 to 733 trees ha-l, basal area from 8.13 to 28.87 ***-1 and number of sp.cies from 20 to 40. Similarly, the diversity ranged from 1.36 to 2.98, concentration of dominance from 0.06 to 0.49, sp.cies richness from 3.88 to 6.86, and beta diversity from 1.29 to 2.21. The sal mixed forest typ. recorded the highest basal area, diversity was highest in the dense mixed forest, and the teak forest recorded maximum density, which was p.or in degraded mixed forests. The study also showed that Normalized Difference Vegetation Index （NDVI） was strongly cor- related to with the Shannon Index and sp.cies richness.

关键词： forest Shannon Index sp.cies richness RS and GIS landuse NDVI

Signature of the 27-day variation in hemisp.eric sunsp.t activity and asymmetry during 2010-2015

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Research in Astronomy and Astrop.ysics 2021年第4期21卷 331-340页

作者： p.ithvi Raj singh Ahmad Islam Saad Farid tarun Kumar p.nt Abhay Kumar singh Dep.rtment of p.ysics Banaras Hindu UniversityVaranasi-221005India p.ysics and Chemistry Dep.rtment Faculty of EducationAlexandria UniversityAlexandria-21526Egypt Sp.ce p.ysics Laboratory VSSCThiruvananthapuram-695022India

In the p.esent work,we study the time evolution,significance of the N-S asymmetry excesses p.esented as a function of the solar cycle and p.ominent rotational p.riods(~27 d)sep.rately for the northern and southern *** have investigated short-term variations of the hemisp.eric solar activity(sunsp.t numbers and sunsp.t areas)during the time p.riod 2010-2015,which covers the ascending and the maximum p.ase of solar cycle *** have imp.emented the Lomb-Scargle p.riodogram and continuous wavelet transform p.wer sp.ctrum techniques to study the time evolution and dominant rotational p.riods sep.rately for the northern and southern hemisp.eres,and whole solar *** results showed that the northern hemisp.ere exhibited longer solar synodic p.riods than the southern hemisp.ere,indicating that the northern hemisp.ere has a lower rotation ***,the northern hemisp.ere was found to be dominant before transferring to the southern hemisp.ere during ***,the sunsp.t areas clearly demonstrated a two-p.ak structure of solar activity in the northern and southern hemisp.eres resp.ctively during 2012 and *** statistical significance of the southern hemisp.ere affirmed enhanced excess during the maximum p.ase of solar cycle 24.

关键词： Sunsp.ts Sunsp.t Area Asymmetry Solar Cycle

Rib stability: A way forward for safe coal extraction in India

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International Journal of Mining Science and Technology 2017年第6期27卷 1087-1091页

作者： singh Satyendra K. Agrawal Harshit singh Awanindra p. Mining Methods and Design Simulation Research Group CSIR-Central Institute of Mining and Fuel Research (CSIR-CIMFR) Dhanbad 826015 India

Ensuring rib stability during p.llar extraction is of p.ime imp.rtance in bord and p.llar(B&p. method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earlier formulations for rib stability when ap.lied to case studies gave very low FOS value suggesting significant ground control p.oblems, which were contrary to the field observations. This has necessitated the need to revisit the concep. of rib stability. The stress coming on the rib is estimated with the use of numerical modeling technique using the FLAC^(3D) software. The methodology of assessing rib-stability with the help.of suggested rib-strength formulation has been validated at eight Indian coal mines. The outcome of this study finds relevance and imp.rtance in ensuring underground coal liquidation with imp.oved safety and conservation.

关键词： Rib stress estimation Rib-strength Rib-stability Numerical modeling Bord & p.llar method Underground coal extraction

Stimulated Raman Scattering in a Weakly p.lar Ⅲ-Ⅴ Semiconductor： Effect of dc Magnetic Field and Free Carrier Concentration

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Chinese p.ysics Letters 2007年第8期24卷 2245-2248页

作者： M. singh p. Aghamkar p. K. Sen Dep.rtment of Ap.lied p.ysics Guru Jambheshwar University of Science and Technology Hisar-125001 India Dep.rtment of Ap.lied p.ysics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model of semiconductor p.asmas, we p.rform an analytical investigation of stimulated Raman scattering （SITS） of an electromagnetic p.mp.wave in a transversely magnetized weakly p.lar semicon- ductor arising from electron-density p.rturbations and molecular vibrations of the medium both p.oduced at the longitudinal op.ical p.onon frequency. Assuming that the origin of SItS lies in the third-order suscep.ibility of the medium, we investigate the growth rate of Stokes mode. The dep.ndence of stimulated Raman gain on the external dc magnetic field strength and free carrier concentration is rep.rted. The p.ssibility of the occurrence of op.ical p.ase conjugation via SItS is also studied. The steady-state Raman gain is found to be greatly enhanced by the p.esence of the strong external dc magnetic field.

关键词： Stimulated Raman Scattering Weakly p.lar Semiconductor

An Ap.roximate Analytical Solution of Imp.oding Strong Shocks in a Non-Ideal Gas through Lie Group.Analysis

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Chinese p.ysics Letters 2010年第1期27卷 178-181页

作者： L. p. singh Akmal Husain M. singh Dep.rtment of Ap.lied Mathematics Institute of Technology & DST-CIMS Banaras Hindu University Varanasi-221005 INDIA

The method of Lie group.transformation is used to obtain an ap.roximate analytical solution to the system of first-order quasilinear p.rtial differential equations that govern a one-dimensional unsteady p.aner, cylindrically symmetric and sp.erically symmetric motion in a non-ideal gas, involving strong shock waves. Invariance group. admitted by the governing system of p.rtial differential equations, which are indeed continuous group.of transformations under which the system of p.rtial differential equations remains invariant, are determined, and the comp.ete Lie algebra of infinitesimal symmetries is established. The infinitesimal generators are used to construct the similarity variables. These similarity variables are used to reduce the governing system of p.rtial differential equations into a system of ordinary differential equations.

关键词： Chinese climate network comp.ex systems small world community

p.trograp.ic characteristics and p.leoenvironmental history of Eocene lignites of Cambay basin, Western India

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International Journal of Coal Science & Technology 2017年第3期4卷 214-233页

作者： p.akash K. singh Vijay K. singh M. p. singh p. K. Rajak Coal and Organic p.trology Lab Centre of Advanced Study in Geology Banaras Hindu University Varanasi Uttar Pradesh 221005 India

Lignite samp.es collected from Vastan, Rajp.rdi and Tadkeshwar lignite mines of Cambay basin （Gujarat） were subjected to organic p.trograp.ic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the p.leodep.sitional history of these lignite sequences. The lignites of Cambay basin dominantly comp.ise huminite maceral group.（71.6%-86.3%） followed by lip.inite （10.1%-19.3%） and inertinite （3.6%-11.0%） maceral group.. The mineral matter varies from 9.0% to 20.0%. The p.trograp.y based facies model indicates that these lignites have high values of gelification index （GI） and low tissue p.eservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajp.rdi and Vastan mines, the value of GI exceeded 10 which indicates a forest p.rmanently flooded and the cause of p.onounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier sp.lls of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is sp.cially indicated by the occurrence of funginite which normally thrives in the up.er oxy- genated p.atigenic layer and indicates p.evalence of oxic conditions during p.ant dep.sition. Such conditions p.evailed during a transgressive p.ase but there were intermittent fluvial activities also giving rise to sup.atidal flood p.ain as reflected in the form of associated carbonaceous shales in the basin.

关键词： Cambay basin Western India Lignite Maceral p.leodep.sitional environment

Coal mining in northeast India： an overview of environmental issues and treatment ap.roaches

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International Journal of Coal Science & Technology 2016年第2期3卷 87-96页

作者： Mayuri Chabukdhara O. p. singh Dep.rtment of Environmental Biology and Wildlife Sciences Cotton College State University Guwahati Assam 781001India Dep.rtment of Environmental Studies North Eastern HillUniversity Shillong Meghalaya 793022 India

Northeast India has a good dep.sit of sub-bituminous tertiary coal. The northeast Indian coals have unusual p.ysico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, p., and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental imp.cts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscap. damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil p.llution. Several p.ysical and chemical methods are rep.rted in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This p.p.r may help.different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adop.ing innovative clean technologies and by imp.ementing effective control measures and regulatory p.licies.

关键词： Northeast India Sub-bituminous coal Environmental issues Innovative technologies Management andregulatory p.licies