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Effect of forest fragment size on tree diversity and population structure of humid subtropical forest of meghalaya, India

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生物多样性 2010年第2期18卷 208-214页

作者： om Prakash Tripathi Khongjee Rangdajied Reynald Department of Botany North Eastern Hill University Shillong-793 022 India Department of Forestry NERIST Nirjuli-791109 India

The present study was conducted in subtropical humid forests of meghalaya to study the distributional pattern of species, floristic composition, community structure and tree population *** fragments of varying sizes(0.5 ha, 1 ha, 2 ha and 5 ha) were used in the *** of the forest fragments are distributed within the same altitudinal range, and had similar rainfall and temperature *** forest fragments were sampled using random quadrats to analyze the impact of fragment size on tree diversity and population *** were used to compare the dispersion pattern of plant species, species diversity am.ng fragments, and the heterogeneity and homogeneity of the fragments.A total of 45 tree species were recorded from all the fragments and simple correlation showed that the species richness was positively related to fragment size(n = 4, Pmeasures such as stand density, basal cover, diversity and dominance indices were unrelated to fragment *** canopy was composed mainly of Castonopsis indica, ***, Schima khasiana and Engelhardtia spicata in all of the fragments.A majority of woody tree species were contagiously distributed which made the forest community highly patchy in *** values of Sorensen's similarity index and high values of Whittaker's β-diversity index between the fragments suggest marked difference in the species composition am.ng the *** maximum stand density, basal area, Shannon diversity index and Simpson dominance index was recorded in a 5-ha *** in lower girth classes(15-55 cm circumference at breast height, CBH) accounted for 52-86% of stand density in all fragments except in 0.5-ha fragments where middle girth class(55-95 cm CBH) accounted for 47% of the total stand *** overall density of seedlings, saplings and adult trees formed a pyramidal structure, indicating that the period between the sapling and adult stage was a critical stage in tree life cycles, as the

关键词：生物多样性相异性指数生态学森林

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Characterization of chickpea germplasm conserved in the Indian national Genebank and development of a core set using qualitative and quantitative trait data

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The Crop Journal 2016年第5期4卷 417-424页

作者： Sunil Archak Rishi K.Tyagi P.n.Harer L.B.mahase neeta Singh om P.Dahiya m.Abdul nizar mohar Singh Vrushali Tilekar Vikas Kumar manoranjan Dutta narendra P.Singh Kailash C.Bansal ICAR-national Bureau of Plant Genetic Resources Pulses Improvement Project Mahatma Phule Krishi Vidyapeeth ICAR-national Bureau of Plant Genetic Resources Regional Station ICAR-Indian Institute of Pulse Research

Chickpea is the third most important pulse crop as a source of dietary protein. Ever-increasing demand in Asian countries calls for breeding superior desi-type varieties, in turn necessitating the availability of characterized germplasm to breeders. The Indian national Genebank,located at the national Bureau of Plant Genetic Resources, new Delhi, conserves 14,651 accessions of chickpea. The entire set was characterized in a single large-scale *** variation was observed for eight quantitative and 12 qualitative agro-morphological traits. Allelic richness procedure was employed to assemble a core set comprising 1103 accessions, 70.0% of which were of Indian origin. Comparable values of total variation explained by the first three principal components in the entire collection(51.1%) and the core(52.4%)together with conservation of nine pairwise r values am.ng quantitative traits in the core collection and a coincidence rate around 99.7% indicated that the chickpea core was indeed an excellent representation of the entire chickpea collection in the national Genebank. The chickpea core exhibited greater diversity than the entire collection in agro-morphological traits, as assessed by higher variance and Shannon–Weaver diversity indices, indicating that the chickpea core maximized the phenotypic diversity available in the Indian chickpea germplasm. The chickpea core, comprising mainly indigenous desi genotypes, is expected to be an excellent resource for chickpea breeders. Information on the chickpea core can be accessed at http://***/pgrportal.

关键词： Cicer arietinum Chickpea germplasm Indian national Genebank Agro-morphological variation Chickpea core

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Synthesis of crystalline perovskite-structured SrTiO_3 nanoparticles using an alkali hydrothermal process

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International Journal of minerals,metallurgy and materials 2016年第1期23卷 109-115页

作者： U.K.n.Din T.H.T.Aziz m.m.Salleh A.A.Umar Institute of microengineering and nanoelectronics (ImEn) Universiti Kebangsaan Malaysia

We report an experimental route for synthesizing perovskite-structured strontium titanate （SrTiO3） nanocubes using an alkali hydrothermal process at low temperatures without further heating. Furthermore, we studied the influence of heating time （at 180℃） on the crystallinity, morphology, and perovskite phase formation of SrTiO3. The SrTiO3 powder, which is formed via nanocube agglomeration, transforms into cubic particles with a particle size of 120--150 nm after 6 h of hydrothermal sintering. The crystallinity and percentage of the perovskite phase in the product increased with heating time. The cubic particles contained 31.24at% anatase TiO2 that originated fi＇om the precursor. By varying the weight ratio of anatase TiO2 used to react with the strontium salt precursor, we reduced the anatase-TiO2 content to 18.8at%. However, the average particle size increased when the anatase-TiO2 content decreased.

关键词： strontium titanate nanoparticles anatase hydrothermal synthesis

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Square-root parametrization of dark energy in f(Q)cosmology

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Communications in Theoretical Physics 2023年第12期75卷 105-114页

作者： m Koussour n myrzakulov Alnadhief H A Alfedeel E I Hassan D Sofuoğlu Safa m mirgani Quantum Physics and magnetism Team LPMCFaculty of Science Ben M'sikCasablanca Hassan II University L.n.Gumilyov Eurasian national University Ratbay myrzakulov Eurasian International Centre for Theoretical Physics Department of mathematics and Statistics Imam Mohammad Ibn Saud Islamic University(IMSIU) Department of Physics Faculty of ScienceUniversity of Khartoum Centre for Space Research North-West University Department of Physics Istanbul University Vezneciler 34134

This paper is a parametrization of the equation of state(Eo S)parameter of dark energy(DE),which is parameterized using square-root(SR)form i.e.ω_(SR)=ω_(0)+ω_(1)z/√z^(2)+1,where ω_(0)and ω_(1) are free *** parametrization is exam.ned in the context of the recently suggested f(Q)gravity theory as an alternative to general relativity(GR),in which gravitational effects are attributed to the non-metricity scalar Q with the functional form f(Q)=Q+αQ^(n),whereαand n are arbitrary *** derive observational constraints on model parameters using the Hubble dataset with 31 data points and the Supernovae(Sne)dataset from the Pantheon samples compilation dataset with 1048 data *** the current model,the evolution of the deceleration parameter,density parameter,EoS for DE,and om(z)diagnostic have all been *** has been shown that the deceleration parameter favors the current accelerated expansion *** has also been shown that the EoS parameter for DE has a quintessence nature at this time.

关键词： cosmology dark energy f(Q)gravity EoS parameter

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The Effects of Zinc Sulfate on the in Vitro Digestibility of Feeds in Cervids

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Open Journal of Animal Sciences 2024年第3期14卷 157-167页

作者： Reese J. Thibodeaux Philip m. Urso Stanley F. Kelley marcy m. Beverly Chris R. Stewart Ian C. Dunn Gentech Diagnostics Dallas Texas USA Department of Animal Science South Dakota State University Brookings South Dakota USA School of Agricultural Sciences Sam Houston State University Huntsville Texas USA 3-S Texas Outdoors/3-S Whitetails Bedias Texas USA

The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. Fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (COn). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in adF, nDF, IVTD, or om between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.

关键词： Zinc IVDmD In Vitro Cervids

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microstructural evolution and mechanical properties of thixoformed A319 alloys containing variable amounts of magnesium

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Transactions of nonferrous metals Society of China 2016年第8期26卷 2029-2042页

作者： m.S.SALLEH m.Z.omAR K.S.ALHAWARI m.n.mOhammED m.A.mad ALI E.mOhamad Department of manufacturing Process Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka Department of mechanical and materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Engineering and Technology Faculty of Information Sciences and EngineeringManagement and Science University

The effects of mg content on the microstructure and tensile properties of thixoformed A319 alloys were studied. The samples were thixoformed at 50% liquid content and some of the thixoformed samples were subjected to the T6 heat treatment. The samples were then exam.ned by optical microscopy (om), scanning electron microscopy (SEm), energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) analysis as well as tensile tests. The results showed that magnesium was able to refine the eutectic silicon in the samples. It was also observed that a compact Al9Femg3Si5 phase was formed when the magnesium content was 1.0% and 1.5%. The results also revealed that as the magnesium content in the alloy increases, the tensile strengths of the thixoformed alloys also increase. The ultimate tensile strength, yield strength and elongation to fracture of the thixoformed A319 heat treated alloy were 298 mPa, 201 mPa and 4.5%, respectively, whereas the values of the thixoformed heat treated alloy with 1.5% mg content were 325 mPa, 251 mPa and 1.4%, respectively. Thixoformed A319 alloy showed a dimple fracture behaviour, while thixoformed A319 alloys with 1.5% mg showed a mixed mode fracture behaviour, where dimple and cleavage ruptures were seen on the fracture surface of the samples.

关键词： aluminium alloy thixoforming T6 heat treatment mechanical properties

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Assessment of fodder quality of leaves of multipurpose trees in subtropical humid climate of India

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Journal of Forestry Research 2008年第3期19卷 209-214页

作者： Chander Datt m. Datta n. P. Singh ICAR Research Complex for nEH Region

The leaves of 12 species （Acacia auriculiformis, Albizzia procera, Dalbergia sissoo, Gliricidia maculata, Leucaena leuco- cephala, Sam.nea sam.n, Azadirachta indica, Eucalyptus hybrida, Gmelina arborea, michelia champaca, morus alba, and Tectona grandis） of multipurpose trees and shrubs （mPTs） grown in the agroforestry arboretum were evaluated for their nutritional characteristics in terms of proximate composition, cell wall constituents, total tannins, major （Ca and P） and trace minerals （Fe, Cu, Zn, mn and Co）, in vitro dry matter and organic matter digestibility （IVDmD and IVomD） and metabolisable energy （mE） values. There were significant （P〈0.01） variations am.ng mPTs for all parameters studied. The average values of （92.02±0.30）%, （16.00±0.74）%, （3.05±0.13）%, （18.97±1.07）%, （54.00±1.12）% and （7.98 ± 0.30）% （Dm basis） were observed for om （organic matter）, CP （crude protein）, EE （ether extract）, CF （crude fibre）, nFE （nitrogen-free extract） and total ash, respectively. Leguminous trees had high CP compared to nonleguminous ones （18.30% vs 13.70%）. The mean values for cell wall constituents viz., nDF （neutral detergent fibre）, adF （acid detergent fibre）, hemi cellulose, cellulose and adL （acid detergent lignin） were found to be （52.48±1.05）%, （31.72±0.97）%, （20.76±0.88）%, （16.97±0.70）% and （9.57±0.62）%, respectively. The total tannin contents averaged （4.22±0.32）%. The ratio of Ca to P was quite wider. The levels of Fe and mn were adequate to rich in all the mPTs while many of the tree species possessed P, Cu, Zn and Co level below the critical limits for the animals. The average IVDmD and IVomD values were found to be （48.96±1.30）% and （50.69±1.36）%, respectively. The mE value averaged （6.95i-0.11） mJ·kg-1 Dm. The CP content had significant positive correlation with IVDmD, IVomD and mE val- ues while nDF, adF, adL and total tannins showed negative correlations with these three parameters. Based on the results, Leucaena Leucocephala could be considered as good q

关键词： agroforestry cell wall composition fodder quality in vitro digestibility proximate composition macro and trace minerals total tannins metabolisable energy multipurpose tree species

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RAnGELAnD RECOVERY TREnDS AFTER THE ESTABLISHmEnT OF COnTOUR BUnDS In SELECTED mICRO-CATCHmEnTS OF THE LAKE VICTORIA BASIn, UGAnDA

RANGELAND RECOVERY TRENDS AFTER THE ESTABLISHMENT OF CONTOUR...

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第九次河流泥沙国际学术大会

作者： n.K.C.ABESIGA m.K mAGUnDA m.J mAJALIWA Institute of Environment and naturai Resources Makerere University Kawanda Agricultural Research Institute Kawanda Agricultural Research Institute

＜正＞Rangeland resource management for sustainable development stili remains one of the unresolved issues facing policy analysis and development agencies in the developing countries. The need for rangeland management to increase rangeland productivity is a pertinent issue because degraded rangelands are a source of pollutants in form of nutrients from runoff. As a result there is increased runoff erosion and deposition, which leads to changes in spatial arrangement of nutrients and plants along the landscape and general reduction of rangeland productivity. Rangeland recovery was investigated on ridges with and without contour bunds, with specific reference to biomass production and soil properties. The study was conducted in Kakuuto County Rakai District Uganda. Biomass production and soil physical and chemical properties were determined along the landscape. Results indicated that, biomass production was higher on ridges with contour bunds （25.6 t·ha-1） compared to ridges without contour bunds （8 t·ha-1） three year after contour bunds establishment （p＜0.05）. Biomass increased logarithmically overtime on ridges with contour bunds and did not significantly change on ridges without contour bunds. Ridges with contour bunds also presented higher values of pH and om （p＜0.05）. Saturated hydraulic conductivity increased from the summit to the foot slope on ridges with contour bunds and remained uniform along the landscape on ridges without contour bunds.

关键词： Rangeland restoration Soil productivity Soil erosion and Species diversity

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Dolomitization in Campanian Oil Shale Rocks from South-Western Jordan

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Open Journal of Geology 2015年第10期5卷 689-700页

作者： Hani m. Alnawafleh Khalid E. Tarawneh Hani n. Khoury nafeth A. Abdelhadi Osama Y. Shakkoury Reyad A. Dwairi mazen n. amaireh Faculty of Engineering Al-Hussein Bin Talal University Ma’an Jordan Faculty of Engineering Isra University Amman Jordan Department of Geology The University of Jordan Amman Jordan Faculty of Engineering Technology Al Balqa Applied University Salt Jordan natural Resources Authority Amman Jordan Faculty of Engineering Tafila Technical University Tafila Jordan

This work represents the first detailed study of an oil shale (OS) section from the Upper Campanian amman Silicified Limestone (ASL) Formation in south-western part of Jordan. more than five meters of oil shale have been recorded. Using the petrography and geochemistry, this study aims to focus on such non-conventional types of oil shale rocks in Jordan and to shed some light on their composition and formational environment. Unlike oil shale from maastrichtian to early Tertiary, this type of oil shale is highly dolomitized. The dolomite is diagenetic in origin. This oil shale type contains considerable amount of om and remarkably enriched in some trace elements and shows quite low sulfur content. Results suggest that the formation of dolomite appears to be limited by the rate of organic matter oxidation.

关键词： Jordan Oil Shale Dolomitization Campanian

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On Probability of Undetected Error for hamming Codes over Q-ary Symmetric Channel

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通讯和计算机（中英文版） 2011年第4期8卷 259-263页

作者： manish Gupta Jaskam Singh Bhullar om Parkash Vinocha D.A.V. College Bathinda 151001 India malout Institute of management and Technology Malout 152107 India Ferozepur College of Engineering and Technology Ferozepur 142052 India

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