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Is Mass-based Metabolism Rate Proportional to Surface Area in Plant Leaves? A Data Re-analysis

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Journal of Integrative Plant Biology 2008年第6期50卷 673-681页

作者： Dongmei Jin Yiqiang Dai Li sun shucun sun Department of Biology Nanjing University Nanjing 210093 China Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 China

We re-analyzed two large published databases on leaf traits of plant species from seven different biomes, and determined the scaling relationship between leaf metabolism rate （mass-based photosynthesis capacity, Amass, and mass-based dark respiration, Rdmass） and specific leaf area （SLA） across biomes, using a standardized major axis （SMA） method. Overall pooled data produced a scaling exponent of 1.33 for the relationship between Amass and SLA, significantly larger than 1.0; and 1.04 between Rdmass and SLA. The scaling exponent of the relationship between Amass and SLA ranged between 1.23 （in tropical forest） and 1.66 （in alpine biome）, and it was significantly larger in alpine （1.66） and grass/meadow （1.52） biomes than in tropical forest （1.23） and wetland （1.27）. The exponent of the relationship between Rdmass and SLA, however, was much smaller in wetland （1.05） than in temperate forest （1.29） and tropical rainforest （1.65）. In general, the predicated universal scaling relationship that the mass-based metabolism rate should be proportional to surface area in organisms is not applicable at the leaf-level in plants. Rather, the large slope difference of the relationship between leaf metabolism rate and SLA found among biomes indicates that the strength of the selective forces driving the scaling relationship is different among the biomes. The result basically suggests the importance of increasing SLA to plant carbon gain in stressful environments and to carbon loss in favorable habitats, and therefore has an important implication for survival strategies of plants in different biomes.

关键词： biome leaf photosynthesis plant respiration specific leaf area scaling

Do plants explore habitats before exploiting them? An explicit test using two stoloniferous herbs

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Chinese Science Bulletin 2012年第19期57卷 2425-2432页

作者： PENG YouHong NIKLAS KarlJ sun shucun Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Department of PlantBiology Cornefl UniversityIthacaNY14850USA Department of Biology Nanjing UniversityNanjing 210093China

We tested whether the processes of exploration and exploitation can be explicitly distinguished as plants grow and develop within a habitat using two stoloniferous clonal herbs,Hydrocotyle sibthorpioides(Umbelliferae) and Potentilla anserina(Rosaceae).Ramets were planted in four circular trays differing in *** replicate from each diameter-group was sampled at intervals corresponding to plant coverage of the trays,and plant biomass allocation to leaves,stolons,and roots and internode length were *** both species,at early sampling times(when the smallest trays were full),total plant biomass and ramet number were larger in the smaller trays than in the larger ***,this trend was reversed for plants collected at later *** ***,leaf mass ratios(leaf mass to total plant mass) were significantly greater,but stolon mass ratios(stolon mass to total plant mass) were less in the small trays than in the larger ones,particularly during the early stages of the ***,for ***,leaf mass ratios decreased in the smaller trays but increased in the larger ones as the experiment *** mass ratios showed contrasting pattern to leaf mass ratios for both species;stolon mass ratios were significantly smaller in the smaller trays than in the larger ones,although there were no obvious patterns during the course of the *** addition,for both species,internode length was shorter but the number of ramets was greater in the smaller trays at early sampling *** conclude that plants invest greater biomass in resource-exploring organs(stolons) than in resource-exploiting organs(leaves or roots) as they initially establish in a *** relatively lower plant productivity in the largest trays at early sampling times presumably reflects the cost of exploration prior to resource exploitation and utilization.

关键词：草本植物匍匐茎栖息地测试采样时间早期阶段物探实验过程

The relationship between relative growth rate and whole-plant C:N:P stoichiometry in plant seedlings grown under nutrient-enriched conditions

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Journal of Plant Ecology 2011年第3期4卷 147-156页

作者： Youhong Peng Karl J.Niklas shucun sun ECORES Lab Chengdu Institute of BiologyChinese Academy of Sciences9 Section 4 Renminnan RoadChengdu 610041China Department of Plant Biology Cornell UniversityIthacaNY 14850USA Department of Biology Nanjing UniversityNanjing 210093China

Aims Recent theories indicate that N is more in demand for plant growth than P;therefore,N concentration and N:C and N:P ratios are predicted to be positively correlated with relative growth rate(RGR)in plants under nutrient-enriched *** prediction was tested in this *** We examined the whole-plant concentrations of C,N and P and RGR,as well as the relationship between RGR and the concentrations and the ratios of N:C,P:C and N:P,for different harvest stages(the days after seed germination)of the seedlings of seven shrub species and four herbaceous species grown in N and P non-limiting *** relationships among plant size,nutrient concentrations and ratios were subsequently *** Findings RGR was positively correlated with N concentration and the ratios of N:PandN:C when the data were pooled for all species and for each shrub species,but not for individual herbaceous ***,the relationship between RGR and P concentration and P:C was not significantly correlated for either shrubs or *** variation of N among harvest stages and species was much greater than that of P,and the variation in N:P ratio was determined primarily by changes in N *** shrub species differed from the herbaceous species in their N and P concentrations,nutrient ratios and in intraspecific relationships between RGR and nutrient *** differences possibly reflect differences in the capacity for P storage and biomass allocation *** general,our data support recent theoretical predictions regarding the relationship between RGR and C:N:P stoichiometry,but they also show that species with different life forms differ in the relationships among RGR and C:N:P stoichimetries.

关键词： C:N:P stoichiometry RGR growth rate hypothesis life forms seedlings screening experiment

Factors shaping life history traits of two proovigenic parasitoids

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Integrative Zoology 2018年第3期13卷 297-306页

作者： Michal SEGOLI shucun sun Dori ENAVA Jay A.ROSENHEIM Mitrani Department of Desert Ecology The Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevMidreshet Ben-GurionIsrael Department of Ecology School of Life ScienceNanjing UniversityNanjingChina Embrapa Clima Temperado(Embrapa Temperate Agriculture) PelotasRio Grande do SulBrazil Department of Entomology and Nematology University of California DavisDavisCaliforniaUSA

What shapes the relative investment in reproduction versus survival of organisms is among the key questions in life *** insects mature all their eggs prior to emergence and are short lived,providing a unique opportunity to quantify their lifetime investments in the different *** investigated the initial eggloads and longevity of 2 proovigenic parasitoid wasps:Anagrus erythroneurae and Anagrus daanei,(Hymenoptera:Mymaridae)that develop within leafhopper eggs in both agricultural vineyards and natural riparian habitats in Northern *** collected Vitis *** containing developing parasitoids from 3 natural sites(Knight Landing,American River and Putah Creek)and 3 agricultural vineyards(Solano Farm,Davis Campus and Village Homes).We recorded eggloads at parasitoid emergence and female parasitoid longevity with or without *** predicts that parasitoids from vineyards(where hosts are abundant)would have higher initial eggloads and lower longevity compared with parasitoids from riparian habitats(where hosts are scarce).Although host density and parasitoid eggloads were,indeed,higher in vineyards than in riparian habitats,parasitoid longevity did not follow the predicted *** without feeding differed among field sites,but it was not affected by habitat type(natural vs agricultural),whereas longevity with feeding was not significantly affected by any of the examined ***,longevity was positively,rather than negatively,correlated with eggloads at the individual level,even after correcting for parasitoid body *** combined results suggest a more complex allocation mechanism than initially predicted,and the possibility of variation in host quality that is independent of size.

关键词： Anagrus parasitoids eggload leafhoppers life-history tradeoffs longevity

Interspecific interactions between burrowing dung beetles and earthworms on yak dung removal and herbage growth in an alpine meadow

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Soil Ecology Letters 2021年第2期3卷 94-102页

作者： MINGDA XIE XINWEI WU shucun sun Department of Ecology College of Life SciencesNanjing UniversityNanjing 210023China

Interspecific interactions between two spatiotemporally co-occurred species sharing a single resource are considered to be either competitive or *** study examined the possible interspecific interactions between a dung-tunneling beetle species(Onthophagus yubarinus)and an earthworm species(Aporrectodea noctuma),two major detritivores responsible for dung removal in a Tibetan alpine *** conducted a two-way,factorial field experiment using replicated chambers,and measured the performances of beetles and earthworms,as well as yak dung removal,soil properties and aboveground plant biomass over two *** presence significantly decreased the body size of beetle larvae and the weight of tunnel dung that beetle larvae live *** contrast,beetle presence did not affect the performance of ***,earthworms and their interaction significantly increased dung removal and soil organic carbon concentration at the end of the *** alone significantly increased soil total N and P,soluble N and P concentrations,but earthworms alone had nonsignificant effects on these nutrient *** and earthworms additively enhanced soluble N and P concentrations,and aboveground plant biomass at the end of the *** results indicate 1)there was a one-sided negative relationship between dung-tunneling beetles and earthworms,resulting from the consumption of earthworms on food resource of beetle larvae;and 2)the coexistence of beetles and earthworms facilitated dung removal interactively and plant growth additively by increasing nutrient availability.

关键词： Detritivore Dung Qinghai-Tibet Plateau Soil animal Species interaction

Linking species performance to community structure as affected by UV-B radiation:an attenuation experiment

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Journal of Plant Ecology 2018年第2期11卷 286-296页

作者： Yangheshan Yang Kechang Niu Zhuomiao Hu Karl J.Niklas shucun sun Department of Ecology School of Life SciencesNanjing University22 Hankou RoadNanjing 210093China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA

Aims UV-B radiation is known to affect plant physiology and growth rate in ways that can influence community species composition and ***,comparatively little is known about how UV-B radiation induced changes in the performance of individual species cascades to affect overall community *** foliage leaves are primarily responsible for photosynthesis and carbon gain and are the major organ that senses and responds to UV-B radiation,we hypothesized that,under reduced UV-B radia-tion,species with larger leaf areas per plant would manifest higher growth rates and hence tend to improve their community status compared to species with smaller leaf areas per plant in herba-ceous plant *** We tested this hypothesis by examining plant traits(leaf area per plant and plant height),plant growth rate(aboveground biomass per plant and plant biomass per area)and community status(spe-cies within-community relative biomass)for 19 common species in a two-year field experiment in an alpine meadow on Tibetan *** findings Aboveground biomass per plant,as well as per area,progressively increased in a 39%reduced(relative to ambient)UV-B treatment dur-ing the experimental *** the second year,11 out of 19 species significantly or marginally significantly increased their plant height,leaf area per plant and aboveground biomass per *** species was negatively affected by reducing *** hypothesized,the increase in aboveground biomass per plant increased with increasing leaf area per plant,as indicated by cross-species regression ***,the change in species within-community status increased with increasing leaf area per *** study demonstrates that UV-B radiation has differential effects on plant growth rate across species and hence significantly affects species composition and plant commu-nity *** suggest that UV-B radiation is an ecological factor structuring plant communities particularly in a

关键词： UV-B radiation leaf area per plant plant growth species assembly community structure alpine meadow Tibetan Plateau

The Discontinuity of Kindergarten Teachers＇ Growth——Analysis Based on Bollnow＇ s Thoughts of ＂Discontinuous Education＂

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International English Education Research 2018年第4期 1-3页

作者： sun shucun Changsha Normal University Changsha 410100

The discontinuous educational thoughts of Bollnow have provided a new perspective for our exploring the growth of Kindergarten teachers and We can rethink the drawbacks of linear development and static thinking with it. Kindergarten teachers＇ growth is the unity of continuity and discontinuity. ＂Crisis＂, ＂encounter＂, ＂awaking＂ and ＂exhortation＂ all can break off the continuity of professional growth of kindergarten teachers, put kindergarten teachers＇ growth into the stage of discontinuity, promote the kindergarten teachers to make a positive self adjustment in shocks, and open up a new stage for kindergarten teachers＇ growth. In order to promote kindergarten teachers＇ active self adjustment in shock, and impel kindergarten teachers to step out oftheir＂comfort zone＂, preschool teachers should try their best to overcome the tendency of＂comfort zone＂ and strengthen the spirit of reflection. The kindergarten should create a rich and colorful cultural environment, and establish a cooperative research community for kindergarten teachers.

关键词： professional growth of kindergarten teachers Bollnow' s "discontinuous educational" thoughts: discontinuity

The abundance effect on network nestedness is stronger for parasitic than herbivory interactions

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Journal of Plant Ecology 2022年第6期15卷 1133-1141页

作者： Bin Lan Xiaoli Hu Ying Wang shucun sun Department of Ecology School of Life ScienceNanjing UniversityNanjing 210023China

It has been suggested that the importance of network architecture to species diversity and stability should be based on preference networks(comprised of niche differentiations),rather than observational networks,because species abundance may significantly affect interaction *** that resource abundance is usually greater for herbivores than parasites,we hypothesize that the abundance effect is stronger for parasitic than herbivory *** test this hypothesis,we collected 80 quantitative observational networks including 34 herbivorous and 46 parasitic networks from the published literature,and derived preference networks by removing the effects of species *** then determined the network nestedness using both weighted NODF and spectral *** also determined species degree distribution,interaction evenness,weighted connectance and robustness for both observational and preference *** observational networks(including both herbivory and parasitic networks)were more nested judged by weighted NODF than spectral *** networks were less nested for parasitic than herbivory networks in terms of both weighted NODF and spectral radius,possibly because removing the abundance effect increased interaction *** trends indicate that the abundance effect on network nestedness is stronger for parasitic than herbivory *** connectance and robustness were greater in most preference networks than observational networks,indicating that preference networks may have high network stability and community persistence compared with observational *** data indicate that future network analyses should not only address the structural difference between mutualistic and antagonistic interactions,but also between herbivory and parasitic interactions.

关键词： network nestedness herbivory network parasitic network preference network species abundance effect on network structure

刺旋花种群形态参数的通径分析与亚灌木个体生物量建模

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应用生态学报 1999年第2期10卷 28-31页

作者：孙书存钱能斌中国科学院成都生物研究所

对刺旋花４种形态参数的通径分析表明，冠幅（Ｃ）对种群生物量作用最大，其它依次为分枝数（ＢＮ）、基径（ＢＤ）和高度（Ｈ）．在此基础上，选取ＣＨ和常用变量Ｄ２Ｈ，就７种常规方程对生物量建模的效果进行比较，并同时建立营养器... 详细信息

对刺旋花４种形态参数的通径分析表明，冠幅（Ｃ）对种群生物量作用最大，其它依次为分枝数（ＢＮ）、基径（ＢＤ）和高度（Ｈ）．在此基础上，选取ＣＨ和常用变量Ｄ２Ｈ，就７种常规方程对生物量建模的效果进行比较，并同时建立营养器官和单株总生物量的预测方程．结果表明，选取变量ＣＨ较Ｄ２Ｈ合适，线性回归方程较其它方程准确直观，其中单株生物量择优预测方程为Ｙ＝１２．１０＋０．０１０５ＣＨ（Ｒ＝０．９８３，Ｐ＜０．０１）．

关键词：刺旋花形态参数通径分析生物量建模