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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)

Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez Carmelo Gómez-Martínez MiguelÁngel Gonzalez-Estévez Amparo Lazaro Mediterranean Institute for Advanced Studies(uib-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks

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

Diet composition of the lizard P odarcis lilfordi (Lacertidae) on 2 small islands: an individualresource network approach

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Current Zoology 2020年第1期66卷 39-49页

作者： Silvia SANTAMARIA Camilla Aviaaja ENOKSEN Jens M.OLESEN Giacomo TAVECCHIA Andreu ROTGER Jose Manuel IGUAL Anna TRAVESET global Change Research Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21E07190 EsporlesMallorcaBalearic IslandsSpain Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityAarhus C8000Denmark Animal Ecology and Demography Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21EsporlesMallorcaBalearic IslandsE07190Spain

Despite it is widely accepted that intrapopulation variation is fundamental to ecological and evolutionary processes,this level of information has only recently been included into network analysis of species/population *** done,it has revealed non-random patterns in the distribution of trophic *** in resource use among individuals is the most recurrent observed pattern,often accompanied by an absence of modularity,but no previous studies examine bipartite *** use network analysis to describe the diet composition of the Balearic endemic lizard Podarcis lilfordi in 2 islets at population and individual levels,based on the occurrence of food items in fecal *** objectives are to 1)compare niche structure at both levels,2)characterize niche partition using nestedness and modularity,and 3)assess how size,sex,season,and spatial location influence niche *** population-level niche width was wide,but narrow at the level of the *** islet networks were nested,indicating similar ranking of the food preferences among individuals,but also modular,which was partially explained by *** and body size did not notably affect diet *** niche overlap and therefore possibly relaxed competition were observed among females in one of the islets and during spring on both ***,higher modularity in autumn suggests that higher competition could lead to specialization in both populations,because resources are usually scarce in this *** absence of spatial location influence on niche might respond to fine-grained spatio-temporally distribution of food *** traits,not included in this study,could also influence resource partitioning.

关键词： Balearic Islands individual diet composition individual-level network modularity nestedness population niche width

Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： Sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUMEU Beatriz GUZMAN Pablo VARGAS Jens M. OLESEN Anna TRAVESET Carlos VERA Edgar BENAVIDES Manuel NOGALES Institut Mediterrani d'Estudis Avanqats (CSIC-uib) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain Department of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador Department of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assumed to be constrained by body size;only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (Microlophus spp.) were studied on the eleven largest Galapagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more importa nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. Most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germi nation inhibitors) might in crease the chances that at least some seeds find suitable recruitment conditi ons. We con eluded that lizards are importa nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： Microlophus oceanic islands plant-animal interactions seed disperser size seed dispersal effectiveness seedling emergence

Floral trait variation across individual plants within a population enhances defense capability to nectar robbing

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Plant Diversity 2023年第3期45卷 315-325页

作者： Shuang Tie Yong-Deng He Amparo Lazaro David W.Inouye You-Hao Guo Chun-Feng Yang College of Life Sciences Wuhan UniversityWuhan 430072China CAS Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China global Change Research Group Mediterranean Institute for Advanced Studies(IMEDEAUIB-CSIC)EsporlesBalearic IslandsSpain The Rocky Mountain Biological Laboratory Post Office Box 519Crested ButteCO 81224USA Department of Biology University of MarylandCollege ParkMD 20742USA

Floral trait variation may help pollinators and nectar robbers identify their target plants and,thus,lead to differential selection pressure for defense capability against floral ***,the effect of floral trait variation among individuals within a population on multi-dimensional plant-animal interactions has been little *** investigated floral trait variation,pollination,and nectar robbing among individual plants in a population of the bumble bee-pollinated plant,Caryopteris divaricata,from which flowers are also robbed by bumble bees with varying intensity across *** measured the variation in corolla tube length,nectar volume and sugar concentration among individual plants,and evaluated whether the variation were recognized by pollinators and *** investigated the in-fluence of nectar robbing on legitimate visitation and seed production per *** found that the primary nectar robber(Bombus nobilis)preferred to forage on plants with long-tubed flowers,which produced less nectar and had lower sugar concentration compared to those with shorter corolla *** with shorter corolla tubes had comparatively lower nectar robbing intensity but higher visitation by legitimate visitors(mainly ***)and higher seed *** robbing signifi-cantly reduced seed production because it decreased pollinator ***,neither pollination nor seed production differed between plants with long and short corolla tubes when nectar robbers were *** finding suggests that floral trait variation might not be driven by *** variation among individual plants thus allows legitimate visitors and nectar robbers to segregate niches and enhances population defense against nectar robbing in unpredictable conditions.

关键词： Bumble bees Caryopteris divaricata Corolla tube Intraspecific variation Plant reproductive success Pollination

Climate warming induced a stretch of the breeding season and an increase of second clutches in a passerine breeding at its altitudinal limits

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Current Zoology 2022年第1期68卷 9-17页

作者： Toni MINGOZZI Pierpaolo STORINO Giampalmo VENUTO Alessandro MASSOLO Giacomo TAVECCHIA Department of Biology Ecology and Earth Sciences(DiBEST)University of CalabriaVia P.BucciRende 87036Italy Department of Biology Ethology UnitUniversity of PisaVia L.Ghini13Pisa 56126Italy UMR CNRS 6249 Chrono-environnement UniversiteBourgogne Franche-Comte16 Route de GrayBesanc¸on 25030France Animal Demography and Ecology Unit(GEDA-IMEDEA CSIC-UIB)C.M.MarquesEsporles 07190Spain

The increase in the average air temperature due to global warming has produced an early onset of the reproduction in many migratory birds of the Paleartic *** to the“mismatch hypothesis”this response can lead to a decrease in the breeding output when the conditions that trigger the departure from the wintering areas do not match the availability of food resources in the breeding *** used 653 brooding events registered during the period 1991–2013 to investigate the link between climatic variables and individual breeding performance of a partially migratory passerine,the Rock Sparrow Petronia petronia,breeding at the altitude limit of its *** laying date(LD)of the earliest first clutch was associated with local spring(minimum)temperatures but did not show a significant trend during the period *** LD of the latest first clutch had a positive and statistically significant trend,unrelated to local covariates and resulting in a longer breeding season(1.5 days/year).A longer breeding season allowed birds to produce more second clutches,which proportion increased from 0.14 to *** average breeding success was also positively correlated with the average temperature in July and with the duration of the breeding *** to expectations,the most important climate-dependent effect was a stretch of the breeding season due to a significant increase of the LD of the latest first-clutches rather than an earlier breeding *** show how climate changes act on bird populations through multiple paths and stress the need to assess the link between climatic variables and several aspects of the breeding cycle.

关键词： breeding phenology climate warming long-term study Petronia petronia reproductive success

CONSORT-公平性2017扩展版及解释:在随机对照试验中更好地报告健康公平性

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英国医学杂志中文版 2018年第12期21卷 712-724页

作者： Vivian A Welch Ole F Norheim Janet Jull Richard Cookson HaIvor Sommerfelt Peter Tugwell 王小琴(译) 杨楠(译) 周奇(译) 张静怡(译) 陈耀龙(校) 杨克虎(校) Methods Centre Bruyere Research InstituteOttawaON Canada School of Epidemiology Public Health and Preventive Medicine University of Ottawa Centre for Intervention Science in Maternal and Child Health (CISMAC) Department of Global Public Health and Primary Care University of Bergen BergenNorway Department of global Health and Population Harvard TH Chan School of Public Health BergenNorway Ottawa Hospital Research Institute University of Ottawa Centre for Health Economics University of York York YO105DD UK Norwegian Institute of Public Health OsloNorway Department of Medicine University of Ottawa 兰州大学循证医学中心

临床试验报告的统一规范(CONSORT)扩展版之CONSORT-公平性(Equity)2017,旨在改善与健康公平性相关的随机对照试验中干预效果的报告质量。健康不公平性是指通过恰当干预可避免的不公平健康差异。健康公平性相关的随机对照试验主要评估对... 详细信息

临床试验报告的统一规范(CONSORT)扩展版之CONSORT-公平性(Equity)2017,旨在改善与健康公平性相关的随机对照试验中干预效果的报告质量。健康不公平性是指通过恰当干预可避免的不公平健康差异。健康公平性相关的随机对照试验主要评估对健康公平性的影响,包括评价针对社会弱势群体的干预措施,探索2个(或2个以上有梯度特征的)处于不同水平的社会弱势群体间干预效果的差异,或两者皆有。我们与来自高、中、低收入国家的多种类型的相关人员进行了共识会议,其中包括知识用户(如患者)和方法学家等。我们围绕各条目讨论了来自实证研究、系统评价、方法学研究、关键人物访谈以及在线调查的证据,在提高报告清晰度的同时尽量避免给作者增加不必要的负担。CONSORT-公平性2017对CONSORT 2010声明中的16个条目进行了扩展,补充了1个有关伦理报告的条目,同时就每个条目提供了报告质量好的实例和简要的解释。广泛应用CONSORT-公平性2017来报告健康公平性相关试验,可促进决策者发现有关的随机对照试验证据并加以应用,从而减少健康不公平性。

关键词：随机对照试验健康公平性 CONSORT 临床试验报告报告质量干预效果弱势群体低收入国家