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Traditional Agrodiversity Management:A Case Study of Central Himalayan Village Ecosystem

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Journal of Mountain Science 2011年第1期8卷 62-74页

作者： Abhishek.chandra P.Pardha SARADHI R.k.MAIk.URI k.G.SAXENA k.S.RAO Department of Environmental Biology University of Delhi G.B.Pant Institute of Himalayan Environment and Development Garhwal UnitSrinagar(Uttarakhand) 246 174India School of Environmental Sciences Jawaharlal Nehru University Department of Botany University of Delhi

Environmental, biological, socio-cultural and economic status variation existing in the Central Himalaya have led to the evolution of diverse and unique traditional agroecosystems, crop species and livestock. which facilitate the traditional mountain farming societies to sustain themselves. Indigenous agroecosystems are highly site specific and differ from place to place, as they have evolved along divergent lines. For maintenance of traditional agrodiversity management the farmers of the Central Himalaya have evolved various types of crop rotations in consonance with the varied environmental conditions and agronomic requirements. In irrigated fiat lands two crops are harvested in a year with negligible fallow period but in rainfed conditions if a cropping sequence is presumed to be starting after winter fallow phase then four major cropping seasons can be identified namely first k.arif season （first crop season）, first rabi season （second crop season）, second k.arif season （third crop season） and second rabi season （fourth crop season）. Highest crop diversity is present in k.arif season in comparison to rabi season. Traditionally the fields are left fallow after harvest of the second k.arif season crop. Important characteristics of agrodiversity management are the use of bullock. for draughtpower, human energy as labour, crop residues as animal feed and animal waste mixed with forest litter as organic input to restore soil fertility levels. Women provide most of the human labour except for ploughing and threshing grain. The present study deals with assessment of traditional agrodiversity management such as （i） crop diversity, （ii） realized yield under the traditional practices and （iii） assess the differences of realized yields under sole and mixed cropping systems. It indicated that crop rotation is an important feature of the Central Himalayan village ecosystem which helps to continue the diversity of species grown, as are the distribution of crops in the growing

关键词： Traditional agricultural practices Himalayas Rainfed Management

Bayesian geological and geophysical data fusion for the construction and uncertainty quantification of 3D geological models

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Geoscience Frontiers 2021年第1期12卷 479-493页

作者： Hugo k.H.Olierook.Richard Scalzo David k.hn Rohitash chandra Ehsan Farahbak.sh Chris Clark.Steven M.Reddy R.Dietmar Müller School of Earth and Planetary Sciences Curtin UniversityGPO Box U1987PerthWA6845Australia Centre for Translational Data Science University of SydneyNSW2006SydneyAustralia Sydney Informatics Hub University of SydneyNSW2006SydneyAustralia EarthByte Group School of GeosciencesUniversity of SydneyNSW2006SydneyAustralia Timescales of Mineral Systems and John de Laeter Centre Curtin UniversityGPO Box U1987PerthWA6845Australia School of Mathematics and Statistics University of New South WalesSydneyNSW2052Australia Department of Mining Engineering Amirkabir University of Technology(Tehran Polytechnic)TehranIran

Traditional approaches to develop 3D geological models employ a mix of quantitative and qualitative scientific techniques,which do not fully provide quantification of uncertainty in the constructed models and fail to optimally weight geological field observations against constraints from geophysical ***,using the Bayesian Obsidian software pack.ge,we develop a methodology to fuse lithostratigraphic field observations with aeromagnetic and gravity data to build a 3D model in a small(13.5 k.×13.5 k.)region of the Gascoyne Province,Western *** approach is validated by comparing 3D model results to independently-constrained geological maps and cross-sections produced by the Geological Survey of Western *** fusing geological field data with aeromagnetic and gravity surveys,we show that 89%of the modelled region has>95%certainty for a particular geological unit for the given model and *** boundaries between geological units are characterized by narrow regions withk. depth,the model requires geophysical survey data with longer wavelengths(e.g.,active seismic)to constrain the deeper *** Obsidian was originally built for sedimentary basin problems,there is reasonable applicability to deformed terranes such as the Gascoyne ***,modification of the Bayesian engine to incorporate structural data will aid in developing more robust 3D ***,our results show that surface geological observations fused with geophysical survey data can yield reasonable 3D geological models with narrow uncertainty regions at the surface and shallow subsurface,which will be especially valuable for mineral exploration and the development of 3D geological models under cover.

关键词： Capricorn orogen Machine learning Bayesian inference Mark.v chain Monte Carlo Solid earth Mineral exploration

Hydro-chemical study of the evolution of interstellar pre-biotic molecules during the collapse of molecular clouds

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Research in Astronomy and Astrophysics 2012年第12期12卷 1613-1624页

作者： Liton Majumdar Ank.n Das Sandip k. Chak.abarti Sonali Chak.abarti Indian Centre for Space Physics Chalantika 43Garia Station RoadKolkata-700084India S.N.Bose National Centre for Basic Sciences Salt LakeKolkata-700098India Maharaja Manindra chandra College 20 Ramakanto Bose StreetKolkata-700003India

One of the stumbling block. for studying the evolution of interstellar molecules is the lack.of adequate k.owledge about the rate coefficients of various reactions which tak. place in the interstellar medium and molecular *** theoretical models of rate coefficients do exist in the literature for computing abundances of complex pre-biotic *** far these have been used to study the abundances of these molecules in ***,in order to obtain more accurate final compositions in these media,we have calculated the rate coefficients for the formation of some of the most important interstellar pre-biotic molecules by using quantum chemical *** use these rates inside our hydro-chemical model to examine the chemical evolution and final abundances of pre-biotic species during the collapsing phase of a *** find that a significant amount of various pre-biotic molecules could be produced during the collapse phase of a *** thoroughly study the formation of these molecules via successive neutral-neutral and radical-radical/radicalmolecular *** present the time evolution of the chemical species with an emphasis on how the production of these molecules varies with the depth of a cloud. We compare the formation of adenine in interstellar space using our rate-coefficients and using those obtained from existing theoretical *** routes of the pre-biotic molecules are found to be highly dependent on the abundances of the reactive species and the rate coefficients involved in the *** presence of grains strongly affects the abundances of the gas phase *** also carry out a comparative study between different pathways available for the synthesis of adenine,alanine, glycine and other molecules considered in our *** the huge abundances of the neutral reactive species,production of adenine is found to be strongly dominated by the radical-radical/radical-molecular reaction *** all the reactio

关键词： ISM clouds-astrochemistry-stars formation

Ultrasound‑assisted osmotic dehydration,followed by convective drying of papaya:effect on physicochemical and functional quality parameters

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Systems Microbiology and Biomanufacturing 2023年第4期3卷 615-626页

作者： Abhishek.chandra Sourabh k.mar Sachin k.mar Prabhat k.mar Nema Department of Food Engineering National Institute of Food Technology Entrepreneurship and ManagementSonipat 131028India School of Health Sciences and Technology University of Petroleum and Energy StudiesDehradunUttarakhandIndia

Papaya is a rich source of nutrients,antioxidants,and vitamins;however,it is highly perishable and hence needs to be preserved using suitable unit *** is an economical method of papaya treatment,but results in the loss of essential nutrients and also degrades its pigments,color,and ***,this work.aims to utilize ultrasound and osmotic dehydration as pretreatment strategies to preserve the rich composition of papaya during conventional hot air *** dried papaya slices were evaluated for moisture content,water activity,total phenolic content,β-carotene,color,antioxidant activity,microstructure,and *** showed that sample pretreatment with 33 k.z ultrasound frequency and dehydrated with 35°Brix osmotic solution resulted in lower moisture content(showed a more porous *** study concludes that pretreatment of papaya slices with ultrasound and osmotic dehydration is recommended before drying.

关键词： Carica papaya Microstructure Carotenoids Texture Drying Pretreatment

The local contribution to the microwave back.round radiation

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Research in Astronomy and Astrophysics 2015年第4期15卷 461-474页

作者： Jean-Claude Peck.r Jayant V.Narlik.r Francois Ochsenbein chandra Wick.amasinghe College de France Inter-University Centre for Astronomy and Astrophysics Centre de Donnees astronomiques de Strasbourg (CDS) Observatoire de Strasbourg11rue de l’Universite 67000 StrasbourgFrance Buck.ngham Centre for Astrobiology University of Buckingham

The observed microwave back.round radiation （MBR） is commonly in- terpreted as the relic of an early hot universe, and its observed features （spectrum and anisotropy） are explained in terms of properties of the early universe. Here we describe a complementary, even possibly alternative, interpretation of MBR, first proposed in the early 20th century, and adapt it to modern observations. For example, the stellar Hipparcos data show that the energy density of starlight from the Milk. Way, if suit- ably thermalized, yields a temperature of ~2.81 k. This and other arguments given here strongly suggest that the origin of MBR may lie, at least in a very large part, in re-radiation of thermalized galactic starlight. The strengths and weak.esses of this alternative radical explanation are discussed.

关键词： Galaxy: stellar content -- (cosmology:) cosmic microwave back.round-- cosmology: observations

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数据库查询理论

计算机科学 1992年第5期19卷 71-77页

作者： Ashok.k.chandra 范明

一、引言从 Codd 引进关系数据库开始,在理解怎样才能从数据库中提取数据方面已做了大量工作。已经提出和开发了许多数据库系统和查询语言,包括 SQL,QBE,QUEL,L-DL 等。与此同时,数据库的查询理论已成长为一个丰满的技术领域,这一发展... 详细信息

一、引言从 Codd 引进关系数据库开始,在理解怎样才能从数据库中提取数据方面已做了大量工作。已经提出和开发了许多数据库系统和查询语言,包括 SQL,QBE,QUEL,L-DL 等。与此同时,数据库的查询理论已成长为一个丰满的技术领域,这一发展把更重实效的开发建立在对问题的全面理解之上。确实,现在逻辑程序设计方面开展的研究就是这种情况。本文的目的不是全面地综述数据库查询理论,而是指出随着该领域的发展,使得该领域成型的一些思想。二、一阶查询和关系代数第一个重要的思想来自 Codd。

关键词：数据库查询

Impact of Elevated CO2on Wheat Growth and Yield under Free Air CO2Enrichment

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American Journal of Climate Change 2017年第4期6卷 573-596页

作者： Vivek.Pandey Marisha sharma Farah Deeba Vivek.k. Maurya Sunil k. Gupta Satyendra P. Singh Aradhana Mishra chandra shek.ar Nautiyal Plant Ecology & Environmental Sciences CSIR-National Botanical Research Institute Lucknow India Division of Plant Microbe Interaction CSIR-National Botanical Research Institute Lucknow India

Impact of elevated CO2 (free air CO2 enrichment) was studied on wheat (Triticum aestivum L. var k.ndan) growth, yield and proteome. Elevated CO2 significantly impacted both underground (+24%) and aboveground (+15%) biomass. Grain weight/plant and harvest index were increased by 35% and 11.4%, respectively under high CO2. On the other hand, seed protein content was decreased by 19% under CO2 enrichment while seed starch and soluble sugar contents were increased by 8% and 23%, respectively. Wheat leaf proteomics revealed that 50 proteins were showing differential expression. Twenty proteins were more abundant while 30 were less abundant. Thirty two proteins were identified by MALDI TOF TOF. More abundant proteins were related to defense, photosynthesis, energy metabolism etc. While less abundant proteins were related to glycolysis and gluconeogenesis. Wheat grain proteomics revealed that out of 49 differentially abundant proteins, 24 were more in abundance and 25 were less in abundance in wheat grains under eCO2 condition. Thirty three proteins were identified and functionally characterized. They were found to be involved mainly in carbon metabolism, storage, defence and proteolysis. Gluten proteins are the major component of wheat storage proteins. Our results showed that both high and low molecular weight glutenins were more in eCO2 wheat seeds while there was no change in gliadin evels. This might alter wheat dough strength. Concentration of grain Cr and As was increased at eCO2 while that of Fe, Cu, Zn and Se were found to be decreased. Dynamics of carbon utilization and metabolic abilities of soil microbes under eCO2 were significantly altered. Our study showed that altered wheat seed composition is cause for concern vis-à-vis nutrition and health and for industries which may have implications for agriculturally dominated country lik. India.

关键词： Carbon Dioxide FACE Wheat Proteomics Grain Yield Soil Microbes

Assessment of alpine summit flora in k.shmir Himalaya and its implications for long-term monitoring of climate change impacts

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Journal of Mountain Science 2020年第8期17卷 1974-1988页

作者： Maroof HAMID Anzar Ahmad k.UROO Ak.tar Hussain MALIk.Rameez AHMAD chandra Prak.sh SINGH Centre for Biodiversity&Taxonomy Department of BotanyUniversity of KashmirSrinagar-190006J&KIndia Space Applications Centre Indian Space Research OrganizationAhmedabad-380015India

In an era of climate change,the availability of empirical data on alpine summit vegetation in the Himalaya is still *** we report the assessment of alpine summit flora in Gulmarg Wildlife Sanctuary,k.shmir *** employed a globally standardized Multi-Summit Approach and four spatially isolated summits spanning an elevation gradient of 210 m(between 3530-3740 m a.s.l.)from natural treeline to nival zone were *** of the summits was carried out in the year 2018 to collect floristic data together with records of soil temperature.A total of 142 vascular plant species were recorded in the sampled *** of the species were of herbaceous growth form and with perennial life *** on Raunk.aer’s life form,hemicryptophytes were the most dominant followed by therophytes and *** summit flora showed the predominance of narrow-endemic species,with broad-and non-endemics declining with elevation.A significant relationship between growth form,Raunk.aer’s life form,and the degree of endemism with elevation was *** species diversity and soil temperature showed a monotonic decrease with increasing ***,soil temperature clearly determined the magnitude of species diversity on the ***,based on floristic composition,the lowest summit had the highest dissimilarity with the rest of the *** present study employed globally standardized protocol to scientifically assess the patterns of plant diversity on the alpine mountain summits of k.shmir Himalaya,which in turn has wide implications towards long-term monitoring of climate change impact on alpine biodiversity in the rapidly warming Himalaya.

关键词： Alpine ecosystem Elevation gradient Endemism Himalaya Mountain summits

Metal Salts Assisted Enzyme-Based Extraction of Stevioside from the Leaves of Stevia rebaudianaBertoni

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Advances in Bioscience and Biotechnology 2015年第12期6卷 734-743页

作者： A. Bhask.r Rao Sara A. George Sateesh Alavala H. M. Meshram k. chandra shek.r Medicinal Chemistry and Pharmacology Division CSIR-Indian Institute of Chemical Technology Hyderabad India

Stevioside, extracted from the leaves of Stevia rebaudiana Bertoni, is a natural, high intensity, lowcaloric sweetener with wide therapeutic activities. Conventional stevioside extraction methodologies involve the use of non-green solvents, supercritical fluids, microwaves, etc., however, all these processes are expensive, time-consuming and eco-unfriendly. Therefore an alternative process is desired for the isolation of stevioside. In this study, a novel enzyme-mediated extraction (EME) method has been developed. The dry stevia leaves were pre-treated with hydrolytic enzymes aided by transition metal salts (FeCl3). This was followed by pressurized hot water extraction (PHWE) to release stevioside. The crude extract was purified and clarified through multi-stage membrane filtration. The results confirm that metal salt-assisted cellulase pre-treatment enhanced the yield of stevioside to 72%, with 98% purity, which was higher in comparison to existing methods. Thus, the methodology developed establishes a simple, “green”, enzyme-mediated process for the efficient isolation of stevioside under economical and eco-friendly conditions.

关键词： Stevia rebaudiana Enzyme-Based Extraction Membrane Filtration Stevioside Natural Sweetener