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| 1 | Interspecific and intraspecific variation in specific root length drives aboveground biodiversity effects in young experimental forest stands显示文摘Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our objective was to assess the role of resource partitioning and species interactions as two important mechanisms that can bring about CEs by interspecific and intraspecific trait variation.Methods We measured tree height of 2493 living individuals in 57 plots and specific root length(SRL)on first-order roots of 368 of these individuals across different species richness levels(1,2,4,8 species)in a large-scale forest biodiversity and ecosystem functioning experiment in subtropical China(BEF-China)established in 2009.We describe the effects of resource partitioning between species by a fixed component of interspecific functional diversity(RaoQ)and further effects of species interactions by variable components of interspecific and intraspecific functional diversity(community weighted trait similarity and trait dissimilarity,CWS and CWD).Finally,we examined the relationships between biodiversity effects on stand-level tree height and functional diversity(RaoQ,CWS and CWD)in SRL using linear regression and assessed the relative importance of these three components of functional diversity in explaining the diversity effects.Important Findings Our results show that species richness significantly affected SRL in five and tree height in ten out of 16 species.A positive NE was generally brought about by a positive CE on stand-level tree height and related to high values of RaoQ and CWS in SRL.A positive CE was related to high values of all three components of root functional diversity(RaoQ,CWS and CWD).Our study suggests that both resource partitioning and species interactions are the underlying mechanisms of biodiversity effects on stand-level tree growth in subtropical forest. | Wensheng Bu Bernhard Schmid Xiaojuan Liu Ying Li Werner Härdtle Goddert von Oheimb Yu Liang Zhenkai Sun Yuanyuan Huang Helge Bruelheide Keping Ma | 2017 | Journal of Plant Ecology2017，10，1： | 18 |
| 2 | Positive effects of tree species richness on fine-root production in a subtropical forest in SE-China显示文摘Aims Fine roots play an important role in the biogeochemical cycles of terrestrial ecosystems and are vital for understanding forest ecosystem functioning and services.Higher plant species diversity has been largely reported to increase aboveground community biomass,but how biodiversity affects fine-root production and the related mechanisms in forests remain unclear.In this study,we aim to answer two questions:(i)does fine-root production increase with tree species richness?(ii)Can this effect be explained by niche complementarity among species?Methods We analyzed data from a large forest biodiversity experiment(BEF-China)with 5-year-old trees.Fine-root growth was measured as standing biomass and annual fine-root regrowth was estimated using ingrowth cores.Moreover,relative yield was calculated to test whether over-or under-yielding occurred when mixtures were compared with the average monoculture of the species included in the mixtures.We calculated functional diversity for fine-root(≤2 mm in diameter)traits by Rao’s quadratic entropy index for each species mixture.The effects of manipulated tree species richness and identity on fine-root traits were analyzed with linear mixed-effects models.Mixed models were also used to test the relationships between tree species richness and fine-root standing biomass,annual regrowth and vertical heterogeneity.Important Findings Fine roots of more than one species were found in half of the soil cores in mixtures indicating that belowground interactions in these young forest stands occurred much earlier than canopy closure.We found significant differences among species in fine-root traits such as diameter and specific root length(SRL),which suggested different resource-use strategies and niche partitioning among species.Mean fine-root diameter of species ranged from 0.31 to 0.74 mm,mean SRL ranged from 12.43 m·g^(−1)to 70.22 m·g^(−1)and mean vertical distribution indexβranged from 0.68 to 0.93.There was a significant positive relationship between species richness and the evenness of the vertical distribution of fine-root standing biomass.Moreover,marginally significant positive relationships existed between species richness and standing biomass as well as annual regrowth of fine roots.Relative yields and Rao’s quadratic entropy index were both not significantly affected by species richness.However,the relative yield of fine-root standing biomass was marginally correlated with Rao’s quadratic entropy index,implying that belowground niche complementarity between species does contribute to diversity effects.In conclusion,our study showed positive effects of species richness on the filling of soil volume by fine roots in the studied experimental forest communities.This has positive effects on fine-root standing biomass and may also lead to increased aboveground biomass. | Zhenkai Sun Xiaojuan Liu Bernhard Schmid Helge Bruelheide Wensheng Bu Keping Ma | 2017 | Journal of Plant Ecology2017，10，1： | 14 |
| 3 | Structure of the Upper Mantle and Transition Zone Beneath the South China Block Imaged by Finite Frequency Tomography显示文摘We applied the finite frequency tomography method to S wave data recorded by 350 broadband stations beneath the South China Block(SCB) and its surroundings from earthquakes occurring between July 2007 and July 2010,to better understand upper mantle deformation.Differential travel-times in the pair of stations with appropriate weighting for each station are used in the inversion.Our results are consistent with previous tomography that show a high velocity anomaly beneath the Sichuan basin and a high velocity anomaly in the transition zone beneath the Yangtze Craton.However,the resolution of mantle heterogeneity provides new insight into the tectonic framework of subduction of Burmese lithosphere in the west part of the study region and subduction of oceanic lithosphere in the east.In the subduction realm,west of 107°E,a significant fast S-wave anomaly is located on the southeast of Sichuan Basin.East of 107°E,and two narrow and discontinuous fast S-wave anomalies occur at a depth of 400-600 km beneath the middle of the South China block overlain by the pronounced low S-wave anomalies at a depth of 100 and 400 km.If the fast anomalies located in the mantle transition zone represent stagnant slabs,their fragmented nature may suggest that they could be produced by different episodes of subduction beneath western Pacific island and the above slow velocity anomaly may associated with the back-arc regions of ongoing subduction.In addition,tomography also reveals an anomalously high S-wave velocity continental root extends eastward to a depth 400 km beneath the eastern Sichuan Basin.This anomaly may be related to eastern extrusion of Indian lithosphere associated with the collision of India and Eurasia.Moreover,our results also show large slow anomalies beneath the Red River fault region connected to deeper anomalies beneath the South China Fold Belt and South China Sea.AH these observations are consistent with the scenario that the South China block has been built by both of subduction of Paleopacific plate and eastward subduction of Burma microplate. | SUN Ya LIU Jianxin TANG Youcai CHEN Jiawei ZHOU Keping CHEN Bo | 2016 | Acta Geologica Sinica(English Edition)2016，90，5： | 8 |
| 4 | Coexistence of two sympatric and morphologically similar bat species Rhinolophus affinis and Rhinolophus pearsoni显示文摘Ecologists have long focused on the coexistence of sympatric species. Here, we investigated two horseshoe bat species, Rhinolophus a nis and Rhinolophus pearsoni inhabited in the same cave, for their foraging strategies, niche di erentiation, prey selection, and their coexistence status. These two species of horseshoe bats were di erent in the dominant frequency of their echolocation calls, but similar in their morphology. We found evidence for prey selectivity although there was a high degree of overlap in prey categories and sizes. R. a nis and R. pearsoni foraged on 16 and 7 categories insects, respectively, with Pyralidae, Geometridae, Melolonthidae dominating their diets. The degree of trophic niche overlap was 0.69. Pairwise comparisons suggested that there was no obvious di erentiation in prey categories and size. However, high prey availability in the environment (Simpson diversity index = 0.79 and Margalef richness index = 4.12) contributed to their coexistence by dampening the interspeci c competition. Since there are one or more mechanisms facil- itating species coexistence in a community, our results suggest that the spatial niche di erentiation in foraging microhabitats and in for- aging habitats at landscape scale may promote the coexistence of the two bat species. However, additional eld data are needed to con rm this speculation. | Tinglei Jiang Jiang Feng Keping Sun Jing Wang | 2008 | Progress in Natural Science:Materials International2008，18，5： | 5 |
| 5 | Foraging strategies in the greater horseshoe bat(Rhinolophus ferrumequinum)on Lepidoptera in summer显示文摘The diet of the bat Rhinolophus ferrumequinum was studied at the Zhi’an Village of Ji’an City in China, from June to August 2004. The bats were trained in a laboratory (volume: 9×4×4 m3). Foraging strategies of the bat were ob- served at night and prey remains were collected and identi- fied. The results showed that the diet consisted mainly of Lepidoptera in summer, including 11 families, more than 30 species of moths, such as Noctuidae (36.6% by number), Sphingidae (24.1%), Geometridae (13.4%) and Limacodidae (9.5%). The length of culled wings ranged from 10―40 mm (97.7%). Pearson correlation analysis showed that the bat R. ferrumequinum foraged their prey selectively, but not op- portunistically. From field studies, two ways were observed in which the bats retrieved their prey including aerial hawk- ing during peak active period of the insects and flycatching during the insects’ non-peak activity period. The bats never gleaned prey from the ground, though they appeared to be well able to detect fluttering moths on the ground. | JIN Longru FENG Jiang SUN Keping LIU Ying WU Lei LI Zhenxin ZHANG Xichen | 2005 | Chinese Science Bulletin2005，50，14： | 5 |
| 6 | Early positive effects of tree species richness on soil organic carbon accumulation in a large-scale forest biodiversity experiment显示文摘Aims tree species richness has been reported to have positive effects on aboveground biomass and productivity,but little is known about its effects on soil organic carbon(SOC)accumulation.Methods to close this gap,we made use of a large biodiversity-ecosystem functioning experiment in subtropical china(BEF-china)and tested whether tree species richness enhanced SOC accumulation.In 2010 and 2015,vertically layered soil samples were taken to a depth of 30 cm from 57 plots ranging in tree species richness from one to eight species.Least squares-based linear models and analysis of variance were used to investigate tree diversity effects.Structural equation modeling was used to explore hypothesized indirect relationships between tree species richness,leaf-litter biomass,leaf-litter carbon content,fine-root biomass and SOC accumulation.Important Findings Overall,SOC content decreased by 5.7 and 1.1 g C kg^(-1) in the top 0-5 and 5-10 cm soil depth,respectively,but increased by 1.0 and 1.5 g C kg^(-1) in the deeper 10-20 and 20-30 cm soil depth,respect-ively.converting SOC content to SOC stocks using measures of soil bulk density showed that tree species richness did enhance SOC accumulation in the different soil depths.these effects could only to some extent be explained by leaf-litter biomass and not by fine-root biomass.Our findings suggest that carbon storage in new forests in china could be increased by planting more diverse stands,with the potential to contribute to mitigation of climate warming. | Yin Li Helge Bruelheide Thomas Scholten Bernhard Schmid Zhenkai Sun Naili Zhang Wensheng Bu Xiaojuan Liu Keping Ma | 2019 | Journal of Plant Ecology2019，12，5： | 3 |
| 7 | Development and Evaluation of a Wearable Lower Limb Rehabilitation Robot显示文摘This paper introduces a rigid-flexible coupling wearable exoskeleton robot for lower limb,which is designed in light of gait biomechanics and beneficial for low limb movement disorders by implementing gait training.The rationality of the proposed mechanism is shown with the implementation of the dynamic simulation through MSC ADAMS.For the purposes of lightweight,the exoskeleton mechanism is optimized through finite element analysis.It can be concluded from performance evaluation experiment,the mechanism has certain advantages over existing exoskeleton robots,namely,comfortable,lightweight,low cost,which can be utilized for rehabilitation training in medical institutions or as a daily-walking ancillary equipment for patients. | Wanting Li Keping Liu Chunxu Li Zhongbo Sun Shui Liu Jian Gu | 2022 | Journal of Bionic Engineering2022，19，3： | 2 |
| 8 | A load balancing multi-path routing scheme based on effective voids for optical burst switching networks显示文摘Multi-path routing in the optical burst switching(OBS) networks can reduce the burst loss probability(BLP) by distributing the data burst traffic to multiple paths, compared with single path routing. Unlike the other multi-path routing schemes without considering the carrying capability of the routes, a new multi-path routing scheme based on effective voids(MPEV) is proposed to balance the load of multi-path and reduce the BLP in the paper. MPEV scheme first obtains the information on effective voids of the bottleneck link of multipath by sending a probe packet periodically. The effective voids can accommodate data bursts and accurately represent the available channel resource that is the main determinant of the BLP for OBS networks without optical random access memory. Then MPEV scheme distributes the burst traffic between an ingress node and an egress node to multiple link-disjoint paths by the ratio of the effective voids. More traffic is distributed to the path that has more effective voids, and vice versa. And the distributed amount is proportional to the effective voids of the bottleneck link. So MPEV scheme can balance the load of multi-path routes and can effectively reduce the BLP by avoiding the high load of a single path. And it is easy to implement and agilely adapt to dynamic network traffic. The performance of MPEV scheme is analyzed by queuing theory and is evaluated by simulation. The numerical results show that the proposed scheme can effectively reduce the BLP and balance the traffic load over multiple paths at the same time. | HUANG Sheng ZHANG YunShui SUN Li Qin YANG XiaoLong LONG KePing | 2015 | Science China(Information Sciences)2015，58，2： | 2 |
| 9 | Attack propagation of high-powered intrachannel crosstalk in transparent optical networks显示文摘 | Zeyu Sun Yunfeng Peng Keping Long | 2011 | Optical Engineering2011，50，10： | 1 |
| 10 | Functional trait space and redundancy of plant communities decrease toward cold temperature at high altitudes in Southwest China显示文摘Plant communities in mountainous areas shift gradually as climatic conditions change with altitude. How trait structure in multivariate space adapts to these varying climates in natural forest stands is unclear. Studying the multivariate functional trait structure and redundancy of tree communities along altitude gradients is crucial to understanding how temperature change affects natural forest stands. In this study, the leaf area, specific leaf area, leaf carbon, nitrogen, and phosphorous content from 1,590 trees were collected and used to construct the functional trait space of 12 plant communities at altitudes ranging from 800 m to 3,800 m across three mountains. Hypervolume overlap was calculated to quantify species trait redundancy per community. First,hypervolumes of species exclusion and full species set were calculated, respectively. Second, the overlap between these two volumes was calculated to obtain hypervolume overlap. Results showed that the functional trait space significantly increased with mean annual temperature toward lower altitudes within and across three mountains, whereas species trait redundancy had different patterns between mountains. Thus, warming can widen functional trait space and alter the redundancy in plant communities. The inconsistent patterns of redundancy between mountains suggest that warming exerts varying influences on different ecosystems. Identification of climate-vulnerable ecosystems is important in the face of global warming. | Lan Zhang Xiaojuan Liu Zhenhua Sun Wensheng Bu Franca J.Bongers Xiaoyang Song Jie Yang Zhenkai Sun Yin Li Shan Li Min Cao Keping Ma Nathan G.Swenson | 2023 | Science China(Life Sciences)2023，66，2： | 1 |
| 11 | Simulation Test on Charge Density and Surface Potential in an Oil Tank Dur- ing Filling Operation显示文摘 | Keping Sun Quanzhen Liu Xuewen Li | 2009 | Journal of Electrostatics2009，67，： | 1 |
| 12 | Research on field calculation & safety evaluation in powder silo显示文摘 | SUN Keping YU Geffei | 1998 | Electrostatics1998，44，12： | 1 |
| 13 | Research on field calculation & safety evaluation in powder silo 显示文摘 | Sun Keping Yu Ge-fei | 1998 | J Electrostatics1998，，44： | 1 |
| 14 | Channel power control in optical amplifiers to mitigate physical impairment in optical network显示文摘The signal quality degradation, which occurs due to the aspects of fiber attenuation, splitter switch,and amplified spontaneous noise in erbium-doped fiber amplifier, may substantially erode the performance of optical communications. Among the above-mentioned factors, the physical-layer impairments may significantly weaken the signal quality at the receiver. In this paper, the impact of both the channel power adjustment and the optical signal noise rate on the optimization of optical amplifiers over the optical propagation links is studied.Our objective is to employ a proper control strategy to effectively adjust the signal power level in the chain network. A new algorithm, which takes into account the physical-layer impairments in performance optimization,facilitates an impairment aware-proportional-integral-derivative neuron controller for improving the quality of transmission. Numerical results show that the proposed controller is capable of effectively compensating for the power impairments in optical links. | ZHAO DongYan LONG KePing ZHENG YiChuan SUN Jian GONG WeiBing | 2015 | Science China(Information Sciences)2015，58，10： | 1 |
| 15 | Identification of sympatric bat species by the echolocation calls显示文摘One hundred and thirty-eight echolocation calls of 63 free-flying individuals of five bat species(Rhinolophus ferrumequinum,Myotis formosus,Myotis ikonnikovi,Myotis daubentoni and Murina leucogaster)were recorded(by ultrasonic bat detector(D980))in Zhi’an village of Jilin Province,China.According to the frequency-time spectra,these calls were categorized into two types:FM/CF(constant frequency)/FM(R.ferrumequinum)and FM(frequency modulated)(M.formosus,M.ikonnikovi,M.daubentoni and M.leucogaster).Sonograms of the calls of R.ferrumequinum could easily be distinguished from those of the other four species.For the calls of the remaining four species,six echolocation call parameters,including starting frequency,ending frequency,peak frequency duration,longest inter-pulse interval and shortest inter-pulse interval,were examined by stepwise discriminant analysis.The results show that 84.1%of calls were correctly classified,which indicates that these parameters of echolocation calls play an important role in identifying bat species.These parameters can be used to test the accuracy of general predictions based on bats’morphology in the same forest and can provide essential information for assessing patterns of bat habitat use. | Keping SUN Jiang FENG Longru JIN Ying LIU Yunlei JIANG | 2008 | Frontiers in Biology2008，3，2： | 0 |
| 16 | The dynamic relaxation form finding method aided with advanced recurrent neural network显示文摘How to establish a self‐equilibrium configuration is vital for further kinematics and dynamics analyses of tensegrity mechanism.In this study,for investigating tensegrity form‐finding problems,a concise and efficient dynamic relaxation‐noise tolerant zeroing neural network(DR‐NTZNN)form‐finding algorithm is established through analysing the physical properties of tensegrity structures.In addition,the non‐linear constrained opti-misation problem which transformed from the form‐finding problem is solved by a sequential quadratic programming algorithm.Moreover,the noise may produce in the form‐finding process that includes the round‐off errors which are brought by the approximate matrix and restart point calculating course,disturbance caused by external force and manufacturing error when constructing a tensegrity structure.Hence,for the purpose of suppressing the noise,a noise tolerant zeroing neural network is presented to solve the search direction,which can endow the anti‐noise capability to the form‐finding model and enhance the calculation capability.Besides,the dynamic relaxation method is contributed to seek the nodal coordinates rapidly when the search direction is acquired.The numerical results show the form‐finding model has a huge capability for high‐dimensional free form cable‐strut mechanisms with complicated topology.Eventually,comparing with other existing form‐finding methods,the contrast simulations reveal the excellent anti‐noise performance and calculation capacity of DR‐NTZNN form‐finding algorithm. | Liming Zhao Zhongbo Sun Keping Liu Jiliang Zhang | 2023 | CAAI Transactions on Intelligence Technology2023，8，3： | 0 |
| 17 | Compliant Control of Lower Limb Rehabilitation Exoskeleton Robot Based on Flexible Transmission显示文摘To ensure the safety, comfort, and effectiveness of lower limb rehabilitation exoskeleton robots in the rehabilitation training process, compliance is a prerequisite for human–machine interaction safety. First, under the premise of considering the mechanical structure of the lower limb rehabilitation exoskeleton robot (LLRER), when conducting the dynamic transmission of the exoskeleton knee joint, the soft axis is added to ensure that the rotation motion and torque are flexibly transmitted to any position to achieve flexible force transmission. Second, to realize the active compliance control of LLRER, the sliding mode impedance closed-loop controller is developed based on the kinematics and dynamics model of LLRER, and the stability of the designed control system is verified by Lyapunov method. Then the experiment is designed to track the collected bicycle rehabilitation motion data stably, and the algorithm and dynamic model are verified to satisfy the experimental requirements. Finally, aiming at the transmission efficiency and response performance of the soft shaft in the torque transmission process of the knee joint, the soft shaft transmission performance test is carried out to test the soft shaft transmission performance and realize the compliance of the LLRER, so as to ensure that the rehabilitation training can be carried out in a safe and comfortable interactive environment. Through the design of rehabilitation exercise training, it is verified that the LLRER of flexible transmission under sliding mode impedance control has good adaptability in the actual environment, and can achieve accurate and flexible control. During the experiment, the effectiveness of monitoring rehabilitation training is brought through the respiratory belt. | Keping Liu Li Li Wanting Li Jian Gu Zhongbo Sun | 2023 | Journal of Bionic Engineering2023，20，3： | 0 |
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