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Journal of Mountain Science 2020年第10期17卷 2354-2368页

作者： Parveen K.CHHETRI Raju bISTA krishna b.shrestha Department of Earth Science and Geography California State UniversityDominguez HillsCarsonCalifornia90747USA Department of biological Sciences University of BergenPO Box 7803N-5020BergenNorway

Stand structure dynamics are considered as major happenings in any forest as a response to environmental ***,this important topic is underrepresented in the treeline studies in the Nepal *** aimed to investigate site-as well as species-specific changes in morphometric features(basal diameter,crown cover,density,and height)along the elevational gradient across treeline ecotones in response to recent environmental *** stand structure characteristics of Abies spectabilis,Pinus wallichiana,and betula utilis across the treeline ecotone of three study sites in Eastern(barun),Central(Manang),and Western(Dhorpatan)Nepal were analyzed to elucidate structural ***,eight transects(20 m×(60–250 m))across the treeline ecotone were *** of all life forms,trees(>2 m),saplings(0.5–2 m),and seedlings(basal area increment was higher in barun,but the Manang treeline,despite profound regeneration in recent years,had a low annual basal area ***,the altitudinal distribution of age and morphometry were not consistent among those ***,intra-specific competition was not *** site-specific stand structure dynamics explain why treelines do not respond uniformly to increasing *** invokes,in further studies,the incorporation of the tree’s morphometric adaptation traits,phenotypic plasticity,and interactions between species genotype and the environment.

关键词： Climate change Morphometry Nepal Himalayas Stand structure Treeline Tree-rings

Recent treeline dynamics are similar between dry and mesic areas of Nepal, central Himalaya

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Journal of Plant Ecology 2015年第4期8卷 347-358页

作者： krishna b.shrestha Annika Hofgaard Vigdis Vandvik Department of biology University of BergenPO Box 7803NO-5020BergenNorway Uib Global University of BergenJekteviksbakken 31PO Box 7800NO-5020BergenNorway Norwegian Institute for Nature Research PO Box 5685 SluppenNO-7485TrondheimNorway

Aims We investigated the treeline dynamics of two environmentally con-trasting areas in the Nepalese Himalaya to address the following questions:(i)Does the timing of establishment of the current tree-line differ between the two study areas,and can area-specific tree-line developments be identified?(ii)Do recruitment patterns and height growth indicate recent climate-driven treeline advance,fol-lowing the general prediction for the central Himalayan region,in the two study areas?Methods a dry-climate treeline dominated by Pinus wallichiana and a mesic-climate treeline with Abies spectabilis were selected for *** each area,we sampled the size and age structure of the study spe-cies along three elevational transects(20-m wide)from the forest line to the tree species line crossing the *** also sampled treeline trees from within and outside transects to reconstruct past treeline establishment *** Findings Despite differences in moisture regimes,tree species and recent climate trends,our two study areas showed very similar treeline dynamics over the past six *** both areas,the recruitment of treeline trees indicates stationary treelines over the past six decades with the current treelines being dominated by trees that were established around *** mesic area has experienced an overall climatic warming trend,and the stationary Abies treeline is hypothesized to be regulated by non-climatic factors,notably *** dry area has not experienced warming but increased climatic variability and some very cool summers in the recent dec-ades may explain the stationary to weakly receding Pinus treeline,which appears more climatically controlled with decreased recruit-ment over the past decades and decreased growth towards higher *** both areas,there is a potential for treeline advance,depending on future land use and climate *** results highlight the importance of conducting treeline ecotone analyses for several sites or are

关键词： Abies spectabilis Himalaya Pinus wallichiana slope aspect treeline ecotone dynamics

Topography and human disturbances are major controlling factors in treeline pattern at barun and Manang area in the Nepal Himalaya

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Journal of Mountain Science 2017年第1期14卷 119-127页

作者： Parveen K.CHHETRI krishna b.shrestha David M.CAIRNS Department of Geography Texas A&M University College Station TX 77840 USA Uib Global Jekteviksbakken 31 PO Box 7800 5020 Bergen Norway

The alpine treeline ecotone is an important component of mountain ecosystems of the Nepal Himalaya; it plays a vital role in the livelihood of indigenous people,and provides ecosystem services. However,the region faces a problem of paucity of data on treeline characteristics at the regional and landscape scales. Therefore,we used Remote Sensing(RS),and Geographic Information Science(GIS) approaches to investigate cross-scale interactions in the treeline ecotone. Additionally,European Space Agency land cover map,International Center for Integrated Mountain Development(ICIMOD) land cover map,ecological map of Nepal,and United States Geological Survey Shuttle Radar Topography Mission-Digital Elevation Model were used to analyze treeline pattern at the regional scale. Digital Globe high-resolution satellite imagery of barun(eastern Nepal) and Manang(central Nepal) were used to study treeline patterns at the landscape scale. Treeline elevation ranges from 3300-4300 m above sea level. Abies spectabilis,betula utilis,and Pinus wallichiana are the main treeline-forming species in the Nepal Himalaya. There is an east to west treeline elevationgradient at the regional scale. No slope exposure is observed at the regional scale; however,at the landscape scale,slope exposure is present only in a disturbed area(Manang). Topography and human disturbance are the main treeline controlling factor in barun and Manang respectively.

关键词： Alpine Treeline Mountain ecosystem Himalaya Remote Sensing(RS) Geographic Information Science(GIS)

Assessment of SoilGrids data for soil erosion estimation at watershed scale: A case study in northern Thailand

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Pedosphere 2024年第4期34卷 797-813页

作者： Chike Onyeka MADUEKE Dhruba Pikha shrestha Panagiotis NYKTAS Department of Natural Resources Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Applied Earth Sciences Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Soil Science and Land Resources Management Nnamdi Azikiwe UniversityP.M.B.5025AwkaAnambra State 420110Nigeria

Soil erosion has been identified as one of the most destructive forms of land degradation,posing a threat to the sustainability of global economic,social and environmental *** underscores the need for sustainable land management that takes erosion control and prevention into *** requires the use of state-of-the-art erosion prediction *** models often require extensive input of detailed spatial and temporal data,some of which are not readily available in many developing countries,particularly detailed soil *** soil dataset Global Gridded Soil Information(SoilGrids)could potentially fill the data ***,its value and accuracy for soil erosion modelling in the humid tropics is still unknown,necessitating the need to assess its value vis-à-vis field-based *** major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil *** samples were collected from five physiographic positions(summit,shoulder,back slope,foot slope,and toe slope)using the soil catena *** were collected using a 5-cm steel sample ring(undisturbed)and a spade(disturbed).Data of the landform,predominant vegetation types,canopy cover,average plant height,land use,soil depth,shear strength,and soil color were recorded for each *** soil samples were subjected to laboratory analysis for saturated hydraulic conductivity,bulk density,particle size distribution,and organic matter *** functions were applied on the SoilGrids and field-based data to generate soil hydrological *** resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two *** datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-Finney *** results from both datasets were again compared to determine the degree of *** r

关键词： hillslope modelling pedotransfer function similarity assessment soil erosion modelling soil loss soil survey

Enhancing Economic Cooperation between China and Nepal

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International Understanding 2015年第1期 42-49页

作者： Rajendra b.shrestha Nepal Council of World Affairs(NCWA)Economic Development and International Relations Specialist

China Visit I had an opportunity to visit China,particularly beijing and Eastern coastal cities of Quanzhou and Xiamen in the special economic zone in Fujian Province at the invitation of the Chinese Association for I... 详细信息

关键词： opportunity invitation cooperation Xiamen Fujian neighborhood coastal political India infrastructure

Modification of b3 Model for Sealed Concrete with Additives based on Experimental Observations

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Journal of Donghua University(English Edition) 2011年第1期28卷 79-84页

作者：陈宝春 shrestha krishna Man 李生勇 College of Civil Engineering Fuzhou University

Thirteen specimens were tested out of which nine were for creep of sealed concrete and four for shrinkage test,for a period of 700 d under controlled temperature *** experimental results for creep and shrinkage were compared with creep and shrinkage computation model b3 and distinct discrepancies between observed and calculated creep and shrinkage strains were *** on regression analysis,modification on b3 model has been formulated which will be applicable at least for concrete of characteristics strength of C40 and C50 with ***,on the basis of observation on identical specimens with varied stress strength ratio,a function is generated which accounts effect of stress strength ratio on ***,Civil Engineering community is suggested not to follow the creep prediction models without correction at least for modern concrete,as they do not account the effect of additives on its compliance function.

关键词： stress strength ratio creep test experimental study b3 model regression analysis

The Prevalence and Clinical Manifestations of Co-Infection in Pediatric Infectious Mononucleosis: A Single-Centered, Retrospective Study

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Open Journal of Pediatrics 2024年第3期14卷 459-475页

作者： Abdishakur Abdukadir Muse Zakaria Ahmed Mohamed Pu Yang Lihong Liao bibek Dhar shrestha Agness Nicholaus Kanusya Paul Mwale Youping Deng Dongchi Zhao Department of Pediatrics Zhongnan Hospital of Wuhan University Wuhan China Department of Ophthalmology Zhongnan Hospital of Wuhan University Wuhan China

background: Recent studies indicate that the incidence of infectious mononucleosis (IM) has increased in China. Furthermore, it has been shown that children diagnosed with IM are prone to acquiring other pathogens. However, there is limited research on the prevalence of these co-infections in children with IM. Thus, we conducted this study to determine the prevalence of coinfections and common pathogens, as well as to compare clinical manifestations in children with and without coinfections. Methods: This retrospective observational study was conducted at the Department of Pediatrics Zhongnan Hospital of Wuhan University, Wuhan, China, with data from January 2018 to January 2023. Data, including demographics, symptoms, lab results, and complications, were collected from the hospital’s electronic database and analyzed. The statistical analysis included descriptive statistics, independent samples t-tests and Mann-Whitney tests to compare the means of continuous variables. Statistical significance was determined by p-values less than 0.05. Results: The study involved 216 participants diagnosed with IM, predominantly males (61.6%) aged 0 - 4 years (50.9%). Coinfection was detected in 39.8% of children, with multiple pathogens present in 33.72% of these cases. Among coinfection cases, 40% occurred in children under 5 years old, and females made up 54.2% of these cases. Mycoplasma pneumoniae (MP) was the most prevalent pathogen, accounting for 18.1% of cases. Influenza b (IFb) and Influenza A (IFA) viruses were found in 16.7% and 13.9% of participants, respectively, indicating a notable occurrence of respiratory pathogen coinfections. Male gender, fever, tonsillopharyngitis, lower HGb levels, higher ESR, CRP, and AST levels were correlated with coinfections. Conclusion: In summary, the study revealed a high prevalence of coinfections among children diagnosed with IM, particularly involving Mycoplasma pneumoniae and influenza viruses. These coinfections were notably

关键词： Prevalence Mononucleosis Coinfection Children Epstein-barr Virus Features

Stakeholder Perspectives on Use,Trade,and Conservation of Medicinal Plants in the Rasuwa District of Central Nepal

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Journal of Mountain Science 2011年第1期8卷 75-86页

作者： Yadav UPRETY Ram C.POUDEL Hugo ASSELIN Emmanuel K.bOON krishna K.shrestha Human Ecology Department Vrije Universiteit BrusselLaarbeeklaan 109B-1090 BrusselsBelgium Canada Research Chair in Aboriginal Forestry Université du Québec en Abitibi-Témiscamingue445Boulevard de l'UniversitéRouyn-NorandaQuébecJ9X 5E4Canada Kunming Institute of botany Chinese Academy of Sciences Central Department of botany Tribhuvan University

People's livelihood in several Himalayan regions largely depends on collection,use,and trade of medicinal *** use is generally not a problem,but commercial gathering of selected species to meet increasing national and international demand can result in *** management of medicinal plants requires a clear understanding of the respective roles,responsibilities and viewpoints of the various stakeholders *** personal interviews and group discussions,this study aimed at investigating the views of two stakeholder groups on use,trade and conservation of medicinal plants in the Rasuwa district of *** people and district and national organizations agreed that medicinal plants are collected for a combination of commercial and personal *** on market availability differed significantly:100 % of the respondents from district and national organizations saw markets as easily available,against only 36 % for local *** could explain why medicinal plants were perceived by local people to contribute less to income generation than to livelihood *** viewpoints were also expressed concerning the status of medicinal plants in the district:81 % of the respondents from district and national organizationsconsidered that medicinal plants were threatened,compared to only 28 % for local *** this disparity,both stakeholder groups agreed upon potential threats to medicinal plants:over-harvesting;habitat loss due to land-use change and deforestation;and over-grazing by *** challenges were identified regarding sustainable management of medicinal plants,such as ambiguous policies;lack of resources,information and infrastructures;habitat degradation;and *** these challenges,respondents agreed that the medicinal plants sector offers huge opportunities in the Rasuwa district,given resource availability,community awareness and motivation,and the priority given

关键词： Medicinal plants Livelihood improvement Income generation Himalaya Local people Conservation Policy

Potential cotton aphid, Aphis gossypii, population suppression by arthropod predators in upland cotton

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Insect Science 2013年第6期20卷 778-788页

作者： Ram b. shrestha Megha N. Parajulee Texas A&M University AgriLife Research and Extension Center 1102 E. FM 1294 Lubbock TX 79403 United States

The cotton aphid, Aphis gossypii Glover, predation rate of convergent lady beetle, Hippodamia convergens Guerin-Meneville, was determined by assigning a single predator randomly to each of four prey density treatments in the laboratory. Prey densities included 25, 50, 100, and 200 aphids per Petri dish arena. Predation response was recorded at 1, 4, 8, 16, 24, and 48 h after assigning predators to their prey treatments. Rate of consumption increased through time, with all 25 aphids consumed during the first 4 h of the experiment. At the highest density, adult lady beetle consumed on average 49, 99, 131, 163, 183, and 200 aphids within 1, 4, 8, 16, 24 and 48 h, respectively. Predators showed a curvilinear feeding response in relation to total available time, indicating that convergent lady beetles have the potential to suppress larger populations of aphids through continuous feeding by regulating their predation efficiency during feeding. The analysis of age-specific mortality in absence of prey revealed that lady beetles could survive for an extended period of time （more than 2 weeks） without prey. The ability of a predator to survive without prey delays or prevents the rebound of pest populations that is a significant factor in natural biological control. A two-year field sampling of 10 cotton arthropod predator species showed that spiders （27%） were the most dominant foliage dwelling predators in the Texas High Plains cotton followed by convergent lady beetles （23.5%）, hooded beetles （13.5%）, minute pirate bugs （11%）, green lacewings （9.5%）, bigeyed bugs （7.5%）, scymnus beetles （3%）, soft-winged flower beetles （2%）, damsel bugs （1.5%）, and assassin bugs （1.5%）. A field cage study showed that one H. convergens adult per plant released at prey density of one aphid per leaf kept the aphid population below economic threshold for the entire growing season.

关键词： Aphis gossypii biological control cotton IPM functional response Hippo-damia convergens natural suppression

Adjustment of b3 model for drying concrete with additives based on experimental data

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Journal of Chongqing University 2010年第2期9卷 63-71页

作者： krishna Man shrestha College of Civil Engineering Fuzhou University

All currently avalable concrete creep predicting models cannot describe well the creep of a concrete structure because they all leave the effects of additives out of consideration. The purpose of this work was to modify model b3 for overcoming this deficiency. We tested thirteen specimens of C40 and C50 concrete with additives, out of which nine were for creep and four for shrinkage tests over a 700 d period under controlled temperature. We compared the experimental results for creep and shrinkage with those obtained by using model b3, and derived modification terms through regression analysis. based on the experimental results of identical specimens under varied stress levels, we also derived a function considering the effect of stress level on creep. It is suggested that the creep prediction models without adjustment should not be used for modem concrete with a variety of additives.

关键词： stress strength ratio creep test b3 model regression analysis