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Impact of sole and combined application of biochar,organic and chemical fertilizers on wheat crop yield and water productivity in a dry tropical agro-ecosystem

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Biochar 2019年第2期1卷 229-235页

作者： Rishikesh singh Pardeep singh hema singh A.S.Raghubanshi Integrative Ecology Laboratory(IEL) Institute of Environment and Sustainable Development(IESD)Banaras Hindu UniversityVaranasi 221005India Department of Environmental Studies PGDAV CollegeUniversity of DelhiNew Delhi 110065India Department of Botany Institute of ScienceBanaras Hindu UniversityVaranasi 221005India

Agriculture under changing climate scenario is facing major challenges of water scarcity and resource *** water productivity(WP)may act as an indicator of crop responses to water *** amendments such as biochar and manure application to soil are suggested for improving soil quality and reducing water requirements from agricultural ***,studies exploring the impact of biochar as sole or in combination with organic and/or chemical fertilizers on WP in dry tropical agro-ecosystems are *** this study,we observed the effect of rice-husk ash(RHA,biochar)along with farm-yard manure(FYM)and chemical fertilizers(CF)under varying water conditions on soil hydro-physical properties,yield and WP of wheat ***-filled pore space(WFPS),grain and straw yield,irrigation and total water productivity varied significantly(at P<0.001)at treatment *** and straw yield were found higher under sole and combined CF applied *** and combined RHA and FYM amendment improved water holding capacity(WHC)and WFPS,whereas a decrease in crop yield was observed as compared to the *** and total water productivity were found higher under combined RHA+FYM and sole CF treatments with reduced water supply(except sole CF)as compared to control and sole RHA treatments with full water *** water productivity was found positively correlated with grain and straw yields,however,significant correlations were not observed with WHC and *** indicate that increasing soil hydro-physical properties in silty-loam soil may hinder crop yield and WP under sole biochar applied ***,the implications of the study would help in devising agro-management practices based on combined application of RHA and FYM with reduced chemical fertilizer and water inputs to mitigate the impacts of climate change without compromising crop yield in the highly vulnerable dry tropical agro-ecosystem of ***,long-term studies ar

关键词： Agro-ecosystems Biochar Indo-Gangetic plains Inceptisol Silty-loam texture Water saving

Leaf Construction Cost and Related Ecophysiological Parameters of Rice Crop and Its Important Weeds

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Rice science 2012年第3期19卷 233-240页

作者： Vartika singh hema singh Ecosystems Analysis Laboratory Department of BotanyBanaras Hindu University

To understand the reason for the success of weeds,we investigated the energetic cost of leaf construction,and certain ecophysiological traits of rice and its dominant *** physiological basis among all weeds,Caesulia axillaris Roxburgh was found to be the most serious,followed by Echinochloa cruss-galli *** and Echinochloa colonum ***,while Fimbristylis miliaceae *** and Cyperus iria *** moderate weeds of the rice *** had the lowest leaf construction cost （LCC） both on a mass basis （1.15 g/g） and on a unit area basis （22.93 g/m2）.Comparatively higher specific leaf area,photosynthetic rate,photosynthetic nitrogen use efficiency,leaf area ratio and leaf area index provided *** with further competitive *** LCC suggests that weeds utilize carbon resource more efficiently than the crop and potentially spend the saved energy on other competitive strategies *** production,biomass production and high relative growth rate,which results in low crop yield and increase in weed seed bank.

关键词： Caesulia axillaris Echinochloa cruss-galli leaf construction cost photosynthetic rate rice

Soil Carbon Dynamics Under Changing Climate A Research Transition from Absolute to Relative Roles of Inorganic Nitrogen Pools and Associated Microbial Processes:A Review

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Pedosphere 2017年第5期27卷 792-806页

作者： pratap srivastava rishikesh singh sachchidanand tripathi pardeep singh shikha singh hema singh akhilesh singh raghubanshi pradeep kumar mishra department of chemical engineering and technology indian institute of technologybanaras hindu universityVaranasi 221005(India) institute of environment&sustainable development(iesd) banaras hindu universityVaranasi 221005(India) department of botany deen dayal upadhyaya collegeuniversity of delhiNew Delhi 110015(India) department of environmental studies pannalal girdharlal dayanand anglo-vedic collegeuniversity of delhiNew Delhi 110065(India) ecosystems analysis laboratory department of botanyinstitute of sciencebanaras hindu universityVaranasi 221005(India)

It is globally accepted that soil carbon(C) dynamics are at the core of interlinked environmental problems, deteriorating soil quality and changing climate. Its management remains a complex enigma for the scientific community due to its intricate relationship with soil nitrogen(N) availability and moisture-temperature interactions. This article reviews the management aspects of soil C dynamics in light of recent advances, particularly in relation to the availability of inorganic N pools and associated microbial processes under changing climate. Globally, drastic alterations in soil C dynamics under changing land use and management practices have been primarily attributed to the variation in soil N availability, resulting in a higher decomposition rate and a considerable decline in soil organic C(SOC) levels due to increased soil CO_2 emissions, degraded soil quality, and increased atmospheric CO_2 concentrations,leading to climate warming. Predicted climate warming is proposed to enhance SOC decomposition, which may further increase soil N availability, leading to higher soil CO_2 efflux. However, a literature survey revealed that soil may also act as a potential C sink, if we could manage soil inorganic N pools and link microbial processes properly. Studies also indicated that the relative, rather than the absolute, availability of inorganic N pools might be of key importance under changing climate, as these N pools are variably affected by moisture-temperature interactions, and they have variable impacts on SOC turnover. Therefore, multi-factorial studies are required to understand how the relative availability of inorganic N pools and associated microbial processes may determine SOC dynamics for improved soil C management.

关键词：微生物过程气候变化土壤碳无机氮动力学氮库土壤有机碳二氧化碳浓度

Effect of invasion by Hyptis suaveolens on plant diversity and selected soil properties of a constructed tropical grassland

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Journal of Plant Ecology 2018年第5期11卷 751-760页

作者： Talat Afreen Pratap Srivastava hema singh Jamuna Sharan singh Ecosystems Analysis Laboratory Department of BotanyInstitute of ScienceBanaras Hindu UniversityVaranasi 221005India

Aims Hyptis suaveolens(L.)Poit is an important invader of the tropical and sub-tropical regions of the *** our study,it has been inves-tigated that how does the *** invasion regulate plant spe-cies diversity across the seasons in the dry tropical *** hypothesized that a shift in soil inorganic-N availability is caused by invasion,and this shift is integral to access the invasion effect on plant *** The study was performed in experimental plots at the Botanical Garden of the Banaras Hindu University(25°16′3.3″N and 82°59′22.7″E),Varanasi,Uttar Pradesh,*** replicates(each,2×2m)of non-invaded grassland plots(NIG)and five grassland plots invaded with ***(IG)were *** plots were constructed by transplanting indigenous grassland patches from an adjacent native *** the invaded plots,20 indi-viduals of *** were transplanted per *** 1 year of establishment,diversity attributes and soil properties were recorded from these plots in three seasons as per standard *** Findings The results indicated that Hyptis invasion negatively affects plant diversity,with relatively higher impact in rainy season as compared to the winter *** exhibited lower soil mois-ture content and temperature than NIG in rainy season,whereas soil ammonium-N,nitrate-N,total inorganic-N,N mineralization registered higher values for IG than NIG in both rainy and win-ter *** indices were negatively correlated with soil inorganic-N pool and N ***,these indices were positively correlated with microbial biomass carbon(MBC),and the correlation coefficient for this relationship was higher for rainy season as compared to *** richness(r=0.65)and Shannon diversity(r=0.757)were significantly correlated with the ratio of ammonium-N to *** negative effect of invasion by *** on the plant diversity is possibly mediated by the effect of invasion on N min

关键词： dry tropical grassland diversity Hyptis suaveolens mineralization soil ammonium to nitrate ratio

Identification of SNP and InDel variations in the promoter and 5′ untranslated regions of γ-tocopherol methyl transferase(ZmVTE4) affecting higher accumulation of α-tocopherol in maize kernel

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The Crop Journal 2019年第4期7卷 469-479页

作者： Abhijit Kumar Das Rashmi Chhabra Vignesh Muthusamy hema singh Chauhan Rajkumar Uttamrao Zunjare Firoz Hossain The Indian Council of Agricultural Research (ICAR)-Indian Agricultural Research Institute (IARI) New Delhi 110012 India

Deficiency of vitamin-E or tocopherol causes neurological and cardiovascular disorders in humans. Though maize kernel is rich in total tocopherol, the level of α-tocopherol possessing the highest vitamin-E activity is low. Mutant allele of ZmVTE4 with deletion of 7 bp and 118 bp (0/0: most favorable haplotype) in 5′UTR and promoter region, respectively significantly enhances α-tocopherol in maize kernel than wild type haplotype (7/118).α- tocopherol estimation in 15 diverse inbreds revealed that mean α-/γ-tocopherol and α-/ total-tocopherol was much higher in genotypes with favorable haplotype (1.51 and 0.41) than unfavorable class (0.19 and 0.13), respectively. However even within favorable class,α- tocopherol ranged from 4.76 to 30.07 μg g 1. Sequence analysis of part of 5′UTR and promoter of ZmVTE4 among the genotypes with favorable haplotype revealed 14 SNPs (SNP1 to SNP14) and eight InDels (InDel1 to InDel8). SNP7 at 606 bp (G to A), and InDels viz., InDel1 (27 bp), InDel4 (27 bp) and InDel8 (14 bp) differentiated low and high α-tocopherol accumulating inbreds with favorable haplotype. Hence the newly identified SNP and InDels in addition to the already reported InDels can be useful in selection of favorable genotypes with higher α-tocopherol in maize.

关键词： Maize Vitamin-E InDel SNP Biofortification

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主动雷达截面缩减理论与应用

国外科技新书评介 2016年第8期 16-17页

作者： hema singh 杨盈莹不详中国科学院半导体研究所

雷达是一种电磁波的传感器和探测工具，能主动、实时、远距离、全天候、全天时获取目标信息，能够利用目标对电磁波的反射来发现目标并对目标进行定位。

关键词：雷达截面应用缩减目标信息电磁波传感器远距离全天候

Analytical Estimation of Radar Cross Section of Infinitely Long Conducting Cylinder Coated with Metamaterial

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Computers, Materials & Continua 2016年第6期 199-215页

作者： Girish K. hema singh RV College of Engineering BangaloreIndia CSIR-NAL BangaloreIndia

Aerospace structures can be approximately modeled as a combination of canonical structures such as cylinder,cone and *** the RCS estimation of such canonical structures is of prime *** metamaterials possess peculiar electromagnetic properties which can be useful in modifying the RCS of *** paper is aimed at calculating the RCS of an infinitely long PEC circular cylinder coated with one or two layers of *** incident and scattered fields of coated cylinder are expressed in terms of series summation of Bessel and Hankel *** unknown coefficients of summation are obtained by applying appropriate boundary *** computations are carried out for both principal *** computed results are validated against the numerical-based method of ***,the variation of RCS of the metamaterial coated PEC cylinder with material parameters,frequency,aspect angle and polarization is analyzed.

关键词： Coated Cylinder metamaterial perfect electric conductor radar cross section polarization.

A Multi-Threaded Semantic Focused Crawler

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Journal of Computer Science & Technology 2012年第6期27卷 1233-1242页

作者： Punam Bedi Anjali Thukral hema Banati Abhishek Behl Varun Mendiratta Department of Computer Science University of DelhiDelhi-110007India Department of Computer Science Keshav MahavidyalayaUniversity of DelhiDelhi-110007India Department of Computer Science Dyal Singh CollegeUniversity of DelhiDelhi-110007India

The Web comprises of voluminous rich learning content. The volume of ever growing learning resources however leads to the problem of information overload. A large number of irrelevant search results generated from search engines based on keyword matching techniques further augment the problem. A learner in such a scenario needs semantically matched learning resources as the search results. Keeping in view the volume of content and significance of semantic knowledge, our paper proposes a multi-threaded semantic focused crawler （SFC） specially designed and implemented to crawl on the WWW for educational learning content. The proposed SFC utilizes domain ontology to expand a topic term and a set of seed URLs to initiate the crawl. The results obtained by multiple iterations of the crawl on various topics are shown and compared with the results obtained by executing an open source crawler on the similar dataset. The results are evaluated using Semantic Similarity, a vector space model based metric, and the harvest ratio.

关键词： eLearning semantic focused crawler semantically expanded term ontology