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Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal

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Journal of Mountain Science 2017年第6期14卷 1065-1075页

作者： Yagya P. ADHIKARI Anton FISCHER Hagen S.FISCHER maan b.rokaya Prakash bHATTARAI Axel GRUPPE Geobotany Department of Ecology and Ecosystem Management Technische Universitat Munchen Hans-Carl-von-Carlowitz-Platz 2 85354 Freising Germany Institute of botany Czech Academy of Sciences Zamek 1 CZ-252 43 Pruhonice Czech Republic Department of biodiversity Research Global Change Research Institute Czech Academy of Sciences Belidla 4a 60300 Brno Czech Republic Department of biology University of Bergen Postholes 7803 N-5020 Bergen Norway Zoology - Entomology Department of Animal Science Technische Universitat Munchen Hans-Carl-von-Carlowitz-Platz 85354 Freising Germany

Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observing the patterns of species richness, abundances and species composition of epiphytic orchids and ferns in two subtropical forests in Nepal. We also studied the relationship of host plants(Schima wallichii and Quercus lanata) and epiphyte species. Data were collected in Naudhara community forest(CF) and the national forest(NF) in Shivapuri Nagarjun National Park. The data were analyzed using univariate and multivariate tests. In total, we recorded 41 species of epiphytes(33 orchid and 8 fern species). Orchid species abundance is significantlyhigher in CF compared to NF. Orchid species richness and abundance increased with increasing southern aspect whereas it decreased with increasing canopy cover, and fern species richness increased with host bark roughness. Orchid abundance was positively correlated with increasing bark p H, stem size, tree age and tree height and negatively correlated with increasing steepness of the area. Likewise, fern abundances were high in places with high canopy cover, trees that were tall and big, but decreased with increasing altitude and southern aspect. The composition of the orchid and fern species was affected by altitude, aspect, canopy cover, DbH, number of forks and forest management types. We showed that the diversity of orchid and fern epiphytes is influenced by host characteristics as well as host types. The most important pre-requisite for a high epiphyte biodiversity is the presence of oldrespectively tall trees, independent of the recent protection status. This means:(i) for protection, *** the frame of the national park declaration, such areas should be used which host such old tall trees;and(ii) also in managed forests and even in intensively used landscapes epiphytes can be protected by letting a certain numb

关键词： Environmental factors Epiphytes Large trees Indicator species Multivariate and univariate analyses Permutations tests

butterfly-plant interactions and body size patterns along an elevational gradient in the Manang region of central Nepal

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Journal of Mountain Science 2020年第5期17卷 1115-1127页

作者： bimal Raj SHRESTHA binu TIMSINA Zuzana MüNZbERGOVá Tomás DOSTáLEK Prakash GAUDEL Tej *** maan b.rokaya Central Department of Zoology Tribhuvan UniversityKathmandu44600Nepal Department of Institute of Environmental Studies/botany Faculty of ScienceCharles UniversityBenatska 212801 PragueCzech Republic Department of biodiversity Research Global Change Research CentreCzech Academy of SciencesBelidla 4a60300 BrnoCzech Republic Institute of botany The Czech Academy of SciencesZamek 125243 PruhoniceCzech Republic

butterflies are widely studied due to their key ecosystem *** this reason,they are used in ecosystem assessment,formulating conservation plans and in raising the environmental *** of different factors affecting diversity of butterflies is important for their effective *** this study,we investigated abiotic and biotic factors affecting species richness and community composition of butterflies along an elevational gradient in Manang region,central *** also tested if butterfly species follow the bergmann’s rule.A total of 57 butterfly species belonging to 39 genera and 8 families were recorded in the study *** of a total of 127 plant species identified in the study region,only 67 plant species were visited by butterflies as nectar *** richness of butterflies increased with increasing *** richness was significantly higher in places with shrubs compared to other places and also in autumn than in *** richness of butterflies also depended on composition of plant species occurring at the *** species composition varied among sampling *** was also determined by habitat type,elevation,sampling time,plant species and interactions of elevation×*** relationship between butterfly size and elevation was in the opposite direction than expected according to the bergmann’s *** conclusion,protection of butterfly diversity can only be achieved by protecting different habitats across the diverse physiography of the region and different plant species,in particular herbs and *** results do not support the bergmann’s rule for butterflies along an elevational gradient in our region.

关键词： Lepidoptera Microhabitat Species richness Species composition bergmann’s rule

Variceal hemorrhage:Saudi tertiary center experience of clinical presentations,complications and mortality

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World Journal of Hepatology 2012年第9期4卷 268-273页

作者： Hind I Fallatah Haifaa Al Nahdi maan Al Khatabi Hisham O Akbar Yousif A Qari Abdul Rahman Sibiani Salim bazaraa Department of Medical King Abdul Aziz University Hospital Jeddah Saudi ArabiaJeddah 21423Saudi Arabia

AIM:To determine the clinical presentation,underlying etiology and short-and long-term outcomes of acute variceal bleeding(AVb).METHODS:A retrospective descriptive cohort study of cirrhotic patients with AVb who were admitted to King Abdul Aziz University Hospital between January 2005 and December *** obtained demographic data for all *** each patient we also obtained the clinical data at presentation;cause of liver cirrhosis,bleeding presentation(hematemesis and/or melena),presence of ascites,hepatic encephalopathy and renal impairment(RI) or hepatorenal *** carried out complete blood count,prothrombin time evaluation,and liver function *** also report all episodes of re-bleeding after the first episode of AVb,both during the initial admission and after *** recorded the length of stay for each patient and thereby calculated the mean duration of stay for all *** length of follow-up after the first AVb and the outcome for each patient at the end of the study period were *** of mortality either related to liver disease or non-liver disease cause were ***:A 125 patients were enrolled in the *** number of episodes of AVb for each patients varied between 1 and *** from the first attack of AVb to death was 20.38 mo(SD 30.86),while the length of follow-up for the living patients was 53.58 mo(SD 24.94).Total number of AVb admissions was *** hepatitis C,the commonest underlying etiology for liver disease,was present in 46(36.8%) *** 35(28%) patients had received a primary prophylactic β-blocker before the first bleeding *** mean hemoglobin level at the time of admission was 8.59 g/dL(SD 2.53).Most patients had Child-Pugh Class C 41(32.8%) or Class b 72(57.6%) *** was the predominant symptom and was found in 119(95.2%) patients,followed by melena in 75(60.0%) *** of variable extent was documented in 93(74.4%) *** identified hepati

关键词： Endoscopy Liver disease Mortality Outcome Varices Variceal bleeding

Cranio-cervical bone hyperpneumatization: An overview and illustrative case

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Journal of Acute Disease 2018年第4期7卷 145-148页

作者： Mohammed maan AbdulAzeez Padilla-Zambrano Huber Salima b.Alsaadi Cabreras-Nanclares b.Vladimir Luis Rafael Moscote Salazar Samer S.Hoz College of Medicine Baghdad UniversityBaghdadIraq College of Medicine University of CartagenaCartagena de IndiasColombia Neuroradiology Department Neurosurgery Teaching HospitalBaghdadIraq Department of Neurosurgery Red-Latino-Colombia Neurosurgery Department Neurosurgery Teaching HospitalBaghdadIraq

The pneumatization of regions such as the apex of the temporal crag, the mastoid cells and the perilaberytic region is considered physiological in adults. The process of craniocervical pneumatization in unhealthy adults derives from a dysfunction at the level of the eustachian tube, which provides a valve effect causing an increase in pressure at the level of the middle ear, forcing the entry of air into the dome of the skull through the opening of the occipitomastoidal suture. The process of standard pneumatization of the temporal bones, begins in the final weeks preceding birth, characterized by a decrease in the embryonic mesenchyme at the antrum level and progresses through childhood until adolescence, when the stone portion at the level of the rock is pneumatized;Normal variants have been reported, such as pneumatization that extends from the temporal scale to behind the sigmoid sinus. With regard to the process of hyperneumatization, several etiologies have been proposed that a congenital process versus an acquired process to develop this condition should be compared. The present illustrative case is a seventy-three years old male presented to the outpatient clinic with chronic recurrent occipital headache, already investigated by general practitioner for elevated blood pressure which was excluded. We had checked him to exclude the cervical spinal origin of the occipital headache which was then excluded too. This case scenario demonstrates the debate about how to deal with such cases and thus the review will bring the attention of those who take care of such radiological findings to keep in mind the possible causes and complications according to the reported cases till now. We concluded that the hyperpneumatization of the craniocervical junction is an uncommon radiological finding that is usually asymptomatic although it can entail serious complications in some instances, especially when it enlarges progressively, which may be due to an acquired process. Thus,

关键词： Craniocervical bone Hyperpneumatization of cranial bones

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播种密度和施N肥对春青稞叶片生产的影响

西藏农业科技 1994年第3期16卷 54-59页

作者： A.A.S.maan.D.WRIGHT M.b.ALCOCK 谢慧

1980—1983年在北威尔士学院农场适宜的温室里完成了三个盆栽试验,二个试验测定播期和施N对叶片生长的影响,第三个是测定播种密度和施N对叶片生长的影响,主茎叶片的伸展生长采用一定时间内尺子测量并进行不同播期之间的比较.N肥的增加... 详细信息

1980—1983年在北威尔士学院农场适宜的温室里完成了三个盆栽试验,二个试验测定播期和施N对叶片生长的影响,第三个是测定播种密度和施N对叶片生长的影响,主茎叶片的伸展生长采用一定时间内尺子测量并进行不同播期之间的比较.N肥的增加能加快叶片伸展的速度但是不能影响叶片伸展的持续时间,叶片伸展速度在一定时间内随着茎杆的生长,主茎叶片的递增而加快,叶片伸展的持续时间也随叶片位置的递增而延长.并且与叶片生长期间的平均温度有关,九月份播种的作物通过叶片生长速度较快,持续时间较长来弥补太阳辐射的减弱,六月份播种的作物最长叶片出现在倒数第一茎间上,并且叶片出现较迟,对N反应敏感,叶片伸展速度变化与叶片中H的含量有着明显的联系,密度的加大使主茎上1—4叶片种播的面积增加,之后出现的叶片面积减小,这主要与叶片伸展持续时间的变化有关.叶片生长对作物产量和光合作用是非常重要的,叶片伸展速度和叶片伸展持续时间用L ER和LED来表示,影响叶片生产的主要环境因素是光强度、光量、光周期、温度,水和营养供应,在一般情况下,植物生长经历了温度,光周期和光强度的季节性变化.对环境的控制研究发现这此因素影响着作物的叶片生长.

关键词：叶片生产播种密度主茎叶片播期持续时间盆栽试验营养供应长叶片主要环境因素光量