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Insect Science 2012年第3期19卷 383-390页

作者： Jeffrey A. Harvey Alex Gumovsky Rieta Gols Netherlands Institute of ecology Department of Terrestrial Ecology Wageningen The Netherlands Schmalhausen Institute of Zoology Kiev Ukraine Laboratory of Entomology Plant Science Group Wageningen University Wageningen The Netherlands

Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here we examine the relationship between host cocoon （= pupal） size in the gregarious endoparasitoid wasp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is known about the biology or ecology of this ecto-hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult wasp covaried with the size of the host cocoon at parasitism. Moreover, female wasps were larger than male wasps for a given cocoon size. Adult wasps have remarkably long life-spans, 3 months on average. Longevity did not significantly differ with sex. We also examined how larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, with females taking significantly longer to complete their development than males. In experiments where several eggs of P. semotus were placed on individual pupae of C. glomerata, newly hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they would initiate feeding on host tissues. Our results are discussed in relation to those with other studies with solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.

关键词： Cotesia glomerata growth idiobiont longevity protandry trade-off

Selecting the best:Interspecific and age-related diet differences among sympatric steppe passerines

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Avian research 2023年第4期14卷 611-622页

作者： Julia Zurdo Paula Gomez-Lopez Adrian Barrero Daniel Bustillo-de la Rosa Julia Gomez-Catasús Margarita Reverter Cristian Perez-Granados Manuel B.Morales Juan Traba terrestrial ecology group Department of EcologyUniversidad Autonoma de Madrid(TEG-UAM)MadridSpain Centro de Investigacion en Biodiversidady Cambio Global Universidad Autonoma de Madrid(CIBC-UAM)MadridSpain ecology Department/IMEM“Ramon Margalef” Universidad de AlicanteAlicanteSpain

Parental food provisioning is crucial for the growth and survival of *** rate depends on food quality and food supplied to offspring may differ from what adults use for their *** the case of steppe passerine birds,detailed characterization on nestling dietary composition,as well as prey choice and resource partitioning among species,is a pending *** differences between nestlings and adults remain also largely *** using faecal DNA metabarcoding,we described the diet of nestlings and adults of five shrub-steppe passerine species over the 2017–2019 breeding seasons in central *** also monitored arthropod availability in the field to assess dietary *** expected interspecific dietary differences to limit competition for food resources among sympatric species,as well as parental selection of high quality prey for *** also predicted age-related differences,with nestlings being fed nutrient-rich prey more frequently than *** main arthropod orders provisioned to nestlings were Orthoptera,Julida,Araneae and *** of the different species showed high interspecific diet overlap,indicating both a coincidence in growth needs among bird species and no or little limitation of the most profitable resources during the breeding *** of all species showed higher diet richness than nestlings,and age-related differences in prey composition were mainly driven by the selection of the most easily digestible,larger protein-and calcium-rich prey for nestlings,which may favour their rapid growth,and avoiding highly sclerotized and less nutritional prey such as *** study sheds light on the basic ecology and conservation of these declining steppe birds,indicating that interspecific competition may not be a major factor during the breeding *** the current global decline of arthropods,further long-term research would be necessary,along with the implementation of effective conservation measure

关键词： 18S Faecal material Nestling diet Prey choice Resource partitioning

Frugivory and seed dispersal in the Galápagos:what is the state of the art?

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Integrative Zoology 2011年第2期6卷 110-129页

作者： Ruben HELENO Stephen BLAKE Patricia JARAMILLO Anna TRAVESET Pablo VARGAS Manuel NOGALES Mediterranean Institute of Advanced Studies(CSIC-UIB) Terrestrial Ecology GroupMallorcaBalearic Islands Royal Botanical Garden Madrid(CSIC-RJB) Madrid Island ecology and Evolution research group(CSIC-IPNA) TenerifeCanary IslandsSpain Max Planck Institute for Ornithology Vogelwarte RadolfzellRadolfzellGermany Charles Darwin Foundation Puerto AyoraSanta CruzGalapagosQuitoEcuador

The Galápagos are considered a model oceanic archipelago,with unique flora and fauna currently threatened by alien invasive *** dispersal is an important ecosystem function with consequences for plant population dynamics and vegetation ***,understanding the seed dispersal abilities of the assemblages of frugivores will inform scientists and managers of the dynamics of plant invasions and improve management *** we provide the first comprehensive review of published information on frugivory and animal seed dispersal in the Galá*** collected data from a variety of sources,including notes of the first naturalist expeditions,gray literature available only in Galápagos collections,and peer-reviewed journal ***–animal frugivorous interactions were retrieved from 43 studies and compiled into an interaction matrix describing 366 unique *** studies focused on fruit consumption as a driving force for natural selection,but seed fate was seldom *** most(71%)of the interactions involved native plants,more than one-quarter(28%)involved introduced *** involving birds are considerably more common than those of reptiles and mammals,probably reflecting a research bias towards *** the historical importance of the archipelago as the laboratory for evolutionary and ecological research,understanding of its seed dispersal systems is *** end the review by suggesting 3 priority areas of research on frugivory and seed dispersal in the Galápagos:(i)target research to close knowledge gaps;(ii)the use of a network approach to frame seed dispersal at the community level;and(iii)evaluation of the effect of seed dispersal as a selective pressure acting upon plants and ***,the output of this research has to be properly delivered to the Galápagos National Park Services to help increase management effectiveness.

关键词： conservation planning oceanic islands plant invasions plant-animal interaction seed predation

Functional group richness increases multifunctionality in intensively managed grasslands

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Grassland research 2023年第3期2卷 225-240页

作者： Laura Argens Caroline Brophy Wolfgang W.Weisser Sebastian Meyer terrestrial ecology research group Department for Life Science SystemsSchool of Life SciencesTechnical University of MunichFreisingGermany School of Computer Science and Statistics Trinity College DublinDublinIreland

Background:Agricultural yields have increased continuously over the last few ***,a focus solely on production can harm the *** of agriculture has been suggested to increase production and *** experiments showed positive effects on ecosystems and ***,application of these results to intensively managed grasslands has been questioned due to differences in plant species and management *** on whether diversity can benefit multifunctionality,that is,an integrated index of multiple ecosystem functions,under intensive management,is still ***:To address this,we manipulated plant species richness from one to six species spanning three functional groups(legumes,herbs,and grasses)in intensively managed multispecies grassland leys and examined seven ecosystem ***:We found that multifunctionality increased with functional group and species ***+herb mixtures showed high multifunctionality,while grass monocultures and mixtures with high proportions of grasses had low *** plant species and plant communities drove different ecosystem *** and herbs improved productivity and water availability,while grasses enhanced invasion *** results indicate that multifunctionality and individual ecosystem functions can be promoted through targeted combinations of plants with complementary ecological ***:Plant diversity can improve multifunctionality also under intensive management,potentially benefitting agroeconomics and sustainability.

关键词： biodiversity ecosystem functions intensively managed grassland Legacy Network(LegacyNet) multifunctionality

Delay-constrained sleeping mechanism for energy saving in cache-aided ultra-dense network

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Science China(Information Sciences) 2019年第8期62卷 131-144页

作者： Pei LI Shulei GONG Shen GAO Yaoyue HU Zhiwen PAN Xiaohu YOU National Mobile Communications research Laboratory Southeast University Institute of Space-terrestrial Intelligent Networks School of Electronic Science and EngineeringNanjing University China Mobile group Jiangsu Co. Ltd.

We investigate an energy-saving sleeping mechanism in a cache-aided ultra-dense network(UDN)with delay constraints. As in existing works, we consider the video and file contents of the UDN. The video contents are cached at and delivered by a small-cell base-station(sBS). The cache-aided sBS cooperates with a macro-cell base-station(mBS) to service the file contents. The optimal sleeping strategy that conserves energy under the delay constraint is formulated as an energy-consumption minimization problem under the network stability condition with a guaranteed delay constraint. To find its solution, the minimization problem is transformed into a joint optimization problem of energy consumption and delay by the Lyapunov technique.A delay-constrained sleeping algorithm is proposed, and its effectiveness is confirmed by the numerical results of a simulation study. A tradeoff between energy consumption and delay, achieved by adjusting the weighting factor in the cache-aided UDN, is also demonstrated.

关键词： ultra-dense networks sleeping mechanism mean delay caching strategy energy saving

Mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： Yangyang JIA Marcel G.A.VAN DER HEIJDEN Alain Y.VALZANO-HELD Markus JOCHER Florian WALDER Postdoctoral Mobile Station of ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China research group Plant-Soil Interactions AgroscopeZürich 8046Switzerland research group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland research group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AMF altering plant community ***,we constructed a comprehensive picture of AMF’s role in N cycling,highlighting that AMF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that synergies between AMF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AMF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi

Improving the underwater navigation performance of an IMU with acoustic long baseline calibration

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Satellite Navigation 2024年第1期5卷 224-239页

作者： Paipai Wu Wenfeng Nie Yangfan Liu Tianhe Xu Shandong Key Laboratory of Optical Astronomy and Solar-terrestrial Environment Institute of Space SciencesShandong UniversityWeihai264209ShandongChina research group of Astronomy and Geomatics(gAGE) Universitat Politecnica de Catalunya(UPC)BarcelonaSpain

Underwater acoustic Long-Baseline System(LBL)is an important technique for submarine positioning and ***,the high cost of the seafloor equipment and complex construction of a seafloor network restrict the distribution of the LBL within a small area,making an underwater vehicle difficult for long-distance and high-precision acoustic-based or inertial-based *** therefore propose an acoustic LBL-based Inertial Measurement Unit(IMU)calibration *** the underwater vehicle can receive the acoustic signal from a seafloor beacon,the IMU is precisely calibrated to reduce the cumulative error of Strapdown Inertial Navigation System(SINS).In this way,the IMU is expected to maintain a certain degree of accuracy by relying solely on SINS when the vehicle reaches out the range of the LBL network and cannot receive the acoustic *** present the acoustic LBL-based IMU online calibration model and analyze the factors that affect the accuracy of IMU *** results fulfill the expectation that the gyroscope bias and accelerometer bias are the main error sources that affect the divergence of SINS position errors,and the track line of the underwater vehicle directly affects the accuracy of the calibration *** addition,we deduce that an optimal calibration trajectory needs to consider the effects of the three-dimensional observability and position dilution of *** the experiment,we compare the effects of seven calibration trajectories:straight and diamond-shaped with and without the change of depth,and three sets of curves with the change of depth:circular,S-shaped,and *** them,we find that the figure-eight is the optimal trajectory for acoustic LBL-based IMU online *** take the maintenance period during which the accumulated SINS Three Dimensional(3D)position errors are below 1 km to evaluate the calibration *** filed experimental results show that for the Micro-electromechanical System

关键词： Acoustic LBL Online IMU calibration SINS Relay reference network

Vertical Distribution and Seasonal Fluctuation of Nematode Trophic groups as Affected by Land Use

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Pedosphere 2006年第2期16卷 169-176页

作者： MENG Fan-Xiang OU Wei LI Qi JIANG Yong WEN Da-Zhong Key Laboratory of terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Graduate School of the Chinese Academy of Sciences Beijing 100039 （China）

A field investigation was conducted at the Shenyang Experimental Station of ecology, Chinese Academy of Sciences, in an aquic brown soil of Northeast China under three land use types (cropland, abandoned cropland, and woodland) in order to evaluate whether the vertical distribution and seasonal fluctuation for the number of total nematodes and trophic groups could reflect soil ecosystem differences and to determine the relationships between soil chemical properties and soil nematodes. The majority of soil nematodes were present in the 0-20 cm soil layers, and for these land use types plant parasites were the most abundant trophic group. In the abandoned cropland the numbers of plant parasites reached a peak on the August sampling date, whereas the cropland and woodland peaked on the October sampling date. Meanwhile, in all land use types the number of total nematodes, bacterivores, plant parasites, and omnivores-predators was negatively (P < 0.05, except for bacterivores in cropland, which was not significant) correlated with bulk density, and positively (P < 0.05, except for fungivores in abandoned cropland, which was not significant) correlated with total organic carbon and total nitrogen.

关键词： aquic brown soil land uses soil nematode trophic groups vertical distribution

Urbanization reduces resource use efficiency of phytoplankton community by altering the environment and decreasing biodiversity

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Journal of Environmental Sciences 2022年第2期34卷 140-151页

作者： Yigang Yang Huihuang Chen Mamun Abdullah Al Jean Claude Ndayishimiye Jun R Yang Alain Isabwe Anqi Luo Jun Yang Aquatic EcoHealth group Fujian Key Laboratory of Watershed EcologyKey Laboratory of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Engineering research Center of ecology and Agricultural Use of Wetland(Ministry of Education) College of AgricultureYangtze UniversityJingzhou 434025China

Urbanization often exerts multiple effects on aquatic and terrestrial organisms,including changes in biodiversity,species composition and ecosystem ***,the impacts of urbanization on river phytoplankton in subtropical urbanizing watersheds remain largely ***,we explored the effects of urbanization on phytoplankton community structure(i.e.,biomass,community composition and diversity)and function(i.e.,resource use efficiency)in a subtropical river at watershed scale in southeast China over 6 years.A total of 318 phytoplankton species belonging into 120 genera and 7 phyla were identified from 108 *** biomass showed an increasing trend with increasing urbanization *** phytoplankton community shifted from Chlorophyta dominance in rural upstream waters to Bacillariophyta dominance in urbanized downstream ***,phytoplankton diversity and resource use efficiency(RUE=phytoplankton biomass/total phosphorus)were significantly decreased with increasing urbanization level from upstream to *** RUE exhibited a significant positive correlation with species richness,but a negative correlation with phytoplankton *** variation in environmental factors(turbidity,total nitrogen,NH_(4)^(+)-N,total phosphorus,PO_(4)^(3-)-P and percentage urbanized area)was significantly correlated with phytoplankton diversity and ***,our results revealed the influence of urbanization on phytoplankton community structure and ecosystem function was due to its altering the environmental ***,human-driven urbanization may play crucial roles in shaping the structure and function of phytoplankton communities in subtropical rivers,and the mechanism of this process can provide important information for freshwater sustainable uses,watershed management and conservation.

关键词： Plankton Community functioning Subtropical river Urbanization gradient Land use Watershed ecology

Effects of plant-soil feedback on tree seedling growth under arid conditions

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Journal of Plant ecology 2011年第4期4卷 193-200页

作者： Seline S.Meijer Milena Holmgren Wim H.Van der Putten Resource ecology group Wageningen UniversityPO Box 476700 AA WageningenThe Netherlands University College Dublin Forestry Agriculture&Food Science CentreUniversity College DublinBelfieldDublin 4Ireland World Agroforestry Centre(ICRAF) PO Box 30798LilongweMalawi Department of terrestrial ecology Netherlands Institute of Ecology(NIOO-KNAW)PO Box 506708 PB WageningenThe Netherlands Laboratory of Nematology Wageningen UniversityPO Box 81236700 ES WageningenThe Netherlands

Plants are able to influence their growing environment by changing biotic and abiotic soil *** soil conditions in turn can influence plant growth conditions,which is called plant–soil ***–soil feedback is known to be operative in a wide variety of ecosystems ranging from temperate grasslands to tropical rain ***,little is known about how it operates in arid *** examined the role of plant–soil feedbacks on tree seedling growth in relation to water availability as occurring in arid ecosystems along the west coast of South *** In a two-phased greenhouse experiment,we compared plant–soil feedback effects under three water levels(no water,10%gravimetric moisture and 15%gravimetric moisture).We used sterilized soil inoculated with soil collected from northwest Peru(Prosopis pallida forests)and from two sites in north-central Chile(Prosopis chilensis forest and scrublands without ***).Important Findings Plant–soil feedbacks differed between plant species and soil origins,but water availability did not influence the feedback ***–soil feedbacks differed in direction and strength in the three soil origins ***–soil feedbacks of plants grown in Peruvian forest soil were negative for leaf biomass and positive for root *** contrast,feedbacks were neutral for plants growing in Chilean scrubland soil and positive for leaf biomass for those growing in Chilean forest *** results show that under arid conditions,effects of plant–soil feedback depend upon ***,the results suggest that plant–soil feedback can influence trade-offs between root growth and leaf biomass investment and as such that feedback interactions between plants and soil biota can make plants either more tolerant or vulnerable to *** on dissecting plant–soil feedbacks into aboveground and belowground tissue responses,we conclude that plant–soil feedback can enhance plant colonization in some arid eco

关键词： biomass allocation dry forest facilitation Prosopis South America water pulse